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View Full Version : How good can D.I.Y speakers really get? - Enter Mr Al Newall



SPS
15-01-2009, 13:10
{Moved from Stefano's system pictures thread}



You're welcome, Stefano! And thanks for your comments - we're not big into 'mainstream' anything here; 'outside of the box' thinking is what we promote :)

Marco.


'open baffles' marco, thats my idea of out of the box

some nice kit there stefano

and a good website.. i've been there before, for 124 info page
good stuff..

Marco
15-01-2009, 13:24
LOL. I know, mate - Al brought his ones round last night. I was very impressed, as I think he was with the system and the variety of music we played :)

Marco.

Ali Tait
15-01-2009, 13:42
Let's have some comments then chaps!

Marco
15-01-2009, 14:26
Well, Ali, for the £200 that they cost they are hilariously, laughably, good! In fact, aesthetics aside, they would quite frankly disgrace any sub, say, £3000 commercial speakers I've heard in terms of 'disappearing' and communicating the music minus usual box colorations, and they have all the clarity and detail that you could ever wish for (in fact more so), and also very good bass for OB designs - and they were just simply plonked in front of the Spendors without being in any way ideally positioned.

However, I have to say that I've never heard them sound anywhere near as good at the Owston or Chester fests. Al will comment himself I'm sure, but whether it was the room, the equipment, the set-up thereof, or a combination of all three (and perhaps some other things) to my ears Al's speakers have never 'sung' before anything like what we heard last night, as good as they undoubtedly are with his own kit. Even the cones of the full-range drivers he uses (supposedly) solely to reproduce the midrange and treble frequencies were moving (which they don't normally do in his own system - something which has alerted Al that the frequency response crossover point may need further adjusted) such was the sheer bass energy that was being pumped into the speakers, and those big 15" cones were producing effortless, extended bass, with almost the same visceral impact as the Spendors.

There are areas where the Spendors have more refinement, as one would expect, considering that these are £5.5k loudspeakers, and I could still live with the SP100s, as they are remarkably 'un-boxy' for box speakers (as I'm sure Al will confirm) but at the same time there is a magical openness and clarity with OBs which I would definitely like to explore further with the likes of the Bastanis, which I suspect will be into another league again.

But, as I said, for £200 home-made speakers you quite simply will not get audio performance like it for anything approaching that price commercially. It really does drive the message home just how good D.I.Y audio is when done right. I salute Al for his talent and thank him for his company last night. He arrived at 7pm and didn't leave until midnight. We got through some very varied music in that period and also some home-made Christmas cake! He's most welcome again anytime, as is your good self and Mo :)

Marco.

twogoodears
15-01-2009, 14:47
Because the topic has been raised, my one cent about open-baffles and full-range speakers... I collected over the years some speakers which, cheap or noblest they were, reached an high level of sonic refinement.
Axiom 80s, Siemens KL-306 and 405, Coral's 12" inchers, Zeiss-Ikon 26,5 cm, Green Saba's, Philips 9710's... all the above, in my desert island collection, when I mounted on a large baffle gave to me shivers and great satisfaction... limited but uncompressed dynamics, true to life timbres and coherence...
Horns, their complexities and price-tags, seems simply unnecessary after a careful listening session with these old humble masterpieces.
It's not DIY-ing anymore, but a good-taste exercise and a lesson in sound at home.
As I often say... buy a Philips 9710's pair for cheap and you'll blissfully find best musician's friend.
They're well kept secrets of old-timey good workmanship and materials... and freedom from shops and the like... like becoming actors instead of audience.

SPS
15-01-2009, 15:08
... ooops... thanx for the compliments, BUT be careful in not being confused: Stefano is a quite common name in Italy, like Etienne in France, Stefan in Germany, Stephen or Steve in England or USA, and in "my" very own (i.e. -Stefano Bertoncello) pages, I never covered 124's related topics.

Still hope I'll deserve (some) compliments, anyway... :eyebrows:

sorry stefano, i'm easily confused...read your link to your page and not realised that it was part of the bigger site..

never the less, all very interesting,
i a bit of a collector of hi fi equipment.. and am very impressed with your set up, the more vintage kit i hear ( and own) the more i'm sure modern hi fi is missing something.. well.. missing quite alot really..

i have many of the valves you use, and i've a good idea of the sound that you will be achieving..but thats not like hearing it.. its a shame you are so far away..

Marco, what Al has achieved with quite a low budget is quite remarkable in my veiw.. the costs really start to rise for just slight gains..


steve

twogoodears
15-01-2009, 15:26
Hi Steve... so we share same name:doh::lolsign::)
I'm jealous about your PX25's... the best sound I ever listened - cost no object - was coming from a Axiom 80's baffles-pair fed by single 71A based amps... also love RE-604 and AD-1's DIY amps using 70's Partridges irons and paper-in-oil caps... In my system: too bad I find single WE300B/Partridges amps and autoformers x-overs MUCH better than (better on paper) multiamping, these days... and 10Y, 71A, AD-1 and 45 or 350's have finesse BUT not guts enough for my actual system... too bad.
I tried yesterday evening a couple disks using a DIY amp using 71A and, airy and poetic sound, it lacked the authority and cojones of 300B...
A friend recently improved his 211 single transformers-coupled amps using WE212... i.e. - 211 guts and filament using the same material of WE300B... AMAZING blend of good qualities... for BIG bucks price-tag.
... but Koji at EIFL-Japan still have plenty of these super-triodes... 'til they last.

aquapiranha
15-01-2009, 17:20
IMHO DIY is the way to go. If you can live without the glitzy name tag and the pat on the back from like minded brand hungry forum goers, you can save yourself a bundle and have a fantastic system to boot!

John
15-01-2009, 17:29
I love what Open Baffles do to the sound recently heard the Hawthrone Duet and was very impressed
At the weekend I plan to hear some home made open baffles and Vic will lend me his pair

aquapiranha
15-01-2009, 17:55
I love what Open Baffles do to the sound recently heard the Hawthrone Duet and was very impressed
At the weekend I plan to hear some home made open baffles and Vic will lend me his pair

The two things I would like to try next would be maybe the Hypex amps and also open baffles. I have here a pair each of Fostex FE103E and modified FE206E - I am sure there may be a design for an OB that I could try them in, preferably the 103's and a pair of big woofers!

twogoodears
15-01-2009, 17:58
Owning an embarassing plethora of DIY amps, me and my audio pals sort-of invented a code, nothing special, it's a joke, but... we call our projects with friend name who made or tuned, who gave the haviest foot, better "finger" print to circuit or aesthetic... i.e. - Gianni's transformers-coupled WE300B are leaner than Franz's Partridges/WE300B... Eugenio's RE-604... nice.. well, you got the idea.:smoking:
After this little, cheap, humble, revolutionary "naming", we sort-of gave a new dignity to these painstakingly assembled, tuned and lovingly listened and cherished handicrafts.
As we're all aware, humanity and culture are greatly word-sensitive, and "no-name" is blamed per-se. Try to call your partner: (using a gruntly voice) "hey, woman!"... :lol:
DIY, seems sub-culture, but it's a little better, as it defines an area, at least... but a "Franz's WE300B" sounds (it indeed do!!!) much, MUCH better and makes a world of difference, don't you?
:)

muffinman
15-01-2009, 19:18
Any piccies of these speakers?
i'm looking for a low cost project to get my juices flowing over the next few months

Marco
15-01-2009, 19:24
Gareth,

If you do a search for 'Chesterfest' or 'Owston' and look for the big-ish white, flat, OBs in any of the pics, those are Al's. Otherwise when he gets to this thread he might be able to post some separate pictures :)

Marco.

Beechwoods
15-01-2009, 19:34
IMHO DIY is the way to go. If you can live without the glitzy name tag and the pat on the back from like minded brand hungry forum goers, you can save yourself a bundle and have a fantastic system to boot!

I think this should be added to the 'Ethos' post :) I would always rather have a well made DIY component than spend a wad trying to achieve the same performance with no effort. And that goes as much for DIY equipment bought second hand as stuff I'd made myself (of which I have very little right now, but hope to improve upon soon :))

muffinman
15-01-2009, 20:05
big-ish

I think i'll use that when my wife asks what they'll look like:)

SPS
15-01-2009, 21:21
Hi Steve... so we share same name:doh::lolsign::)
I'm jealous about your PX25's... the best sound I ever listened - cost no object - was coming from a Axiom 80's baffles-pair fed by single 71A based amps... also love RE-604 and AD-1's DIY amps using 70's Partridges irons and paper-in-oil caps... In my system: too bad I find single WE300B/Partridges amps and autoformers x-overs MUCH better than (better on paper) multiamping, these days... and 10Y, 71A, AD-1 and 45 or 350's have finesse BUT not guts enough for my actual system... too bad.
I tried yesterday evening a couple disks using a DIY amp using 71A and, airy and poetic sound, it lacked the authority and cojones of 300B...
A friend recently improved his 211 single transformers-coupled amps using WE212... i.e. - 211 guts and filament using the same material of WE300B... AMAZING blend of good qualities... for BIG bucks price-tag.
... but Koji at EIFL-Japan still have plenty of these super-triodes... 'til they last.

Stefano,
I'm into british valves, px4, px25 and the 2p are my most used output valves..
mainly because i dont need many watts.. a couple is enough.. i have quite a lot of valves.. but there's some i haven't tried.. mostly US types,
i have a nice old pair of 4300a's, they sound very well, i do need to make an amp for them soon

steve

SPS
15-01-2009, 21:31
open baffles.. well i thought a picture of mine might be approprate at this point.. they are quite big but dont look too out of place
the size is the issue with most baffles

I would not get them past every wife i've had...

twogoodears
15-01-2009, 23:09
i have a nice old pair of 4300a's, they sound very well, i do need to make an amp for them soon

... but, if failing (something I'm not wishing, indeed...) on this, I nonetheless kindly ask you to drop me a line... my offer pronto won't be late...

Mo' seriously... nice collection.:smoking:

Marco
15-01-2009, 23:16
I would not get them past every wife i've had...

How many wifes have you had, you sex God? :lol:

Marco.

Beechwoods
15-01-2009, 23:22
I'm not sure if they're all his own... come on, 'fess up, Steve :)

alb
16-01-2009, 08:16
Sorry for being late into this thread. My PC is working at the speed of a snail on valium.

Firstly. Thanks Marco for the hospitality. Even if you're not into this hifi nonsense, it's worth going for his wife's coffee.:)

A worthwhile evening; hope i didn't overstay my welcome. The fact that i was still there at midnight, suggests i was quite happy to listen to your setup.

I was impressed with everything i heard. Some serious dynamics that i don't quite get at home with my SET. More convincing bass than i'm used to.
A nicely balanced system, i would say.
Your Spendors aren't too shabby either - for a box.:lol:

Good to be introduced to some new artists, though i suspect i some of it will sound less interesting on my stuff.

I'll return the favour soon, with a visit to my place. Though you may have to strap a speaker to each ear, to achieve the same volume levels.

Steve S.
I keep meaning to redesign mine, so they look a bit more appealing. But my one and only wife hasn't complained yet. So i get a bit lazy.

More comment later perhaps.

Ali Tait
16-01-2009, 08:30
Hi Marco,
Thanks again for the invite,and yes,will take you up on it sometime.Not sure when,am working 7 days a week at the moment!
Al's system has always sounded excellent to me.Such great sound for so little outlay is a lesson for us all.

SPS
16-01-2009, 09:31
Steve S.
I keep meaning to redesign mine, so they look a bit more appealing. But my one and only wife hasn't complained yet. So i get a bit lazy.

More comment later perhaps.

i' know what you mean about being lazy.. if i did less posting and reading the net i may have time to make the stuff i've had planned

i've only had two wifes in the past,.. i've lived in 'sin' for the last 6 years, she will moan about the kit on a bad day.. but that's all..

the second divorce was within a couple of months of my large horn speakers joining us in the lounge... good move with hindsight.. not at the time

my view now is.. you only get one life.. and you can spend it pleasing her
or pleasing yourself.. i'm somewhere in between that...

large speakers in the lounge are like those wind turbines are to the countryside,... every one complains beforehand.. but one soon gets used to them.. and.. when think about what they do.. there's benefits..

steve

muffinman
16-01-2009, 11:21
Is there a diy source available that can show me what to buy, dimensions and specs that y'all OB experts can point me towards? recommended designs obviously.
I'm hoping to do it on the aforementioned £200ish budget and want it as a suck it and see project. Trouble is, like a lot of people i have limited knowledge of how things work. I can cut wood, solder and test which makes my construction of WD amps and speakers seem a bit more clever than it actually is :)
If any of you chaps have tech details available and is willing to spread the love to someone who wants to give OB a try please - feel free to show me how:)

jonners
16-01-2009, 11:34
muffinman -

The open baffle forum on Audiocircle is a good place to start. I built my OBs as a result of reading the enormous 'Dark Star' thread there. I'm using Visaton B200 8" drivers plus Celestion 15" to boost the bass. That would be more than your budget, but some people are happy with just the B200s, albeit in largeish baffles.

John

muffinman
16-01-2009, 12:07
cheers john,
i'll take a long look at that over the w/e and see what sparks my interest.

SPS
16-01-2009, 17:22
home made open baffles

it actually quite a complicated subject if you read the net.
to be fair it is .. but there is always more than one way to approach it

I'm of the suck it and see type.. so i'll give you my opinion..

1st.. you need to decide on the drivers,
maplin supply the popular 15" emminence speakers,
look at the response graphs.. then choose a full range for the mids/ top.
again, do some research and look at the responses.. with both drivers look at the decibles you get at 1 watt, you want as straight a line as you can get with both drivers combined ... or better still more bass output

then.. a baffle.. look at mine or al's for a rough guide i would recommend flooring grade chipboard, two layers.. mine are up to 2 layers of 25mm.
you can run them both full range to test.. then you can look at crossovers to pad down the peaks . and peaks from where both speakers work to create peaks..



ensure you try them without the cossover so you can listen to the effect of it

there is long write ups on diy audio full range about baffles..

remember the if you want deep bass you may need 2 15" drivers a side then role the upper bass off (a low pass filter) to get the responce level with the smaller driver.. the same applies if you have a bass speaker with more output than the full ranger its paired with


for cutting i would get b&Q to cut the large panels
a router is best for cutting circles, the adjustable guide usually has a central hole that a bolt can be inserted and used as a pivot
look before you buy..

if you build a known plan, you dont learn as much .. but you may get a better speaker to start with..

most drivers have a box to work against, the air in the box works like the springs on a car.( it also affects the sound)
so where a speaker is rated at say 100 watts.. don't turn them up to 100 watts in on open baffles.. they will not work well if you do .. so always well overspec, you will not need many more than 5-8 watts to go loud i would guess
that is a good basis to learn from..
if you dont want to learn the hard way.. just build one of the designs out there..



hope thats some use
steve

Marco
16-01-2009, 17:39
Hi Al,


Sorry for being late into this thread. My PC is working at the speed of a snail on valium.


No worries - I know the feeling!


Firstly. Thanks Marco for the hospitality. Even if you're not into this hifi nonsense, it's worth going for his wife's coffee.


You're very welcome, matey. I'll tell Del you liked her frothy little concoction!


A worthwhile evening; hope i didn't overstay my welcome. The fact that i was still there at midnight, suggests i was quite happy to listen to your setup.


Nope not at all - that's the advantage of having an understanding wife and no neighbours! :eyebrows:

Indeed it was a most worthwhile evening and we must do it again sometime. As you can tell, I was impressed with your cheeky white boxes!


I was impressed with everything i heard. Some serious dynamics that i don't quite get at home with my SET. More convincing bass than i'm used to.
A nicely balanced system, i would say.
Your Spendors aren't too shabby either - for a box.


Well that last comment is important simply because as a non-OB user I have no real way of knowing how 'boxy' or otherwise my speakers sound. As you say, they seem pretty good in that respect, which was proven when after listening to the SP100s for a period of time we concluded that your OBs didn't sound too remarkably different in the areas you would expect them to be.

Further listening afterwards when you had gone confirmed that very little readjustment by my ears was required in terms of the 'magic' OB factor having being removed from the equation, which for my bank balance (in terms of the Bastani factor) could be a very good thing ;)

But we shall see what happens - it's still an itch I have to scratch!


Good to be introduced to some new artists, though i suspect i some of it will sound less interesting on my stuff.


I'll see if I can knock up a playlist of the tunes we listened to. It might take a while, though!


I'll return the favour soon, with a visit to my place. Though you may have to strap a speaker to each ear, to achieve the same volume levels.


LOL. I'll look forward to that - I could always bring the Copper amp with me to guarantee the same 'disco' levels if you can square it with the necessary parties concerned :gig:

Marco.

twogoodears
16-01-2009, 18:07
A nice site:

http://www.maclementhorn.it/PHY-HP_Open_Baffle.html

... also worth exploring proved using the different sized "wings" option, pals... will post project and pixes soon.

twogoodears
16-01-2009, 18:15
http://www.phy-hp.com/English/Communication_E/Com_E_Baffle_Plan.html

Used this with my Philips 9710 and... well, it's nothing less than incredible... also in no-sand, no-frill, no-hassle version, as I lazily did.

Baffles aren't always special in super-heavy plywood... must tune-in: say 18 mm on 10 inches wideband and up to 25 mm with 15" woofers...

John
16-01-2009, 18:30
I love what open baffles do but must admit I am a bit scared by the DIY side and will it work in my room. I would want really good bass the kind that does kick drums well yet has no sense of overhang
I now heard the Atlas just a great speaker and the Hawthrone Duet which I need to hear again under better condictions. On Saturday i am off to hear another Open Baffle system
I cannot afford the Atlas and the Hawthorne I would need another amp as well and not really looking at adding another power amp into the system so seems to rule out that option. Maybe Saturday might prove more fruitfull

alb
16-01-2009, 19:45
Open baffles don't get much more simple than mine. Just two or three bits of MDF, which you can get cut to size. The wiring and crossover is deliberately minimal. You can make some alterations to the shape to improve aesthetics, without seriously affecting the sound.

http://i27.photobucket.com/albums/c164/alnewall/Baffles.jpg

http://i27.photobucket.com/albums/c164/alnewall/amp007.jpg

The above photos are old and do not show the low pass filter on the bass driver.

Beechwoods
16-01-2009, 19:57
They look really nice. Even from the back they look well thought out and the wiring is neat :) You might give people some ideas :)

Marco
16-01-2009, 20:01
They sound bloody good, too, Beechy! I'm not easily impressed ;)

Marco.

John
16-01-2009, 20:18
Wow nice speakers
I am not worried about the woodwork but no experience of designing a crossover so its stuff like that really has stopped me so far

alb
16-01-2009, 20:36
No need to design a crossover. No need to overcomplicate matters.

Mine uses a low pass filter from Maplins on the bass driver. If Maplins no longer sell them, i've seen similar things on Ebay. Mine feeds the bass driver with frequencies up to around 120Hz.

Then it's just one capacitor in line with the full range driver to keep out the bass. Again this should cut in at around 120Hz.
Maybe a resistor as well to prevent the FR driver output overpowering the bass driver. The whole thing can be easily and cheaply tuned for personal preference or for different drivers..

Marco
16-01-2009, 23:30
Al, how did you get on with that movement in the 'full range' driver cones - did it do the same thing back at yours? :)

Marco.

alb
17-01-2009, 09:55
Dunno what it is, Marco. Everything seems ok. Doesn't do it here at the volume i play at.
Might just be a reflection of the bass wave off the Spendors, which were right behind.

Ali Tait
17-01-2009, 10:13
Anyone thinking about building these,just go ahead! It really doesn't get any easier than this and yes,they sound superb.As Al said,the good thing is you can easily tune them to your taste/room.The folding baffle is an excellent idea also.You can open them out for listening,and fold them away when not in use for better WAF.

twogoodears
17-01-2009, 10:34
When I built the "PHY" style w/different wings size open baffle with piano-hinges, I lived happily for some weeks as I used some paperwall I had handy on front-panel which she loved... much more than my horns(speakers), actually.

BTW: please use birch plywood, NOT MDF... IMHO it's a sound-killer... NOT a killer-sound:smoking:
Also worth considering as a top-quality baffle material, a Panzerholz 25 mm thickness... http://www.ltlewis.co.uk/b15.htm

My apologies for (someway) playing the "I-know-all role"... please note the IMHO foreword:)

Marco
17-01-2009, 10:47
Dunno what it is, Marco. Everything seems ok. Doesn't do it here at the volume i play at.
Might just be a reflection of the bass wave off the Spendors, which were right behind.

Yes, that could well have been the reason, although it was interesting that it was happening on one speaker more than on the other... I think what we should perhaps do is for me to bring my kit to yours (everything minus the speakers) and see if it happens again. I think it's also partly to do with how they're being driven.

It's an interesting one for sure!

Marco.

muffinman
17-01-2009, 11:20
Excellent info here. My mind and heart are set and i'll definatley be doing a straight rip off of alb's design. it's gonna take a few months so i can slip it under the wifedar - no mean feat as she's an air traffic controller:lol:
I'd like to use veneered mdf for the baffle so i can get a pretty finish should i like them. this stuff can be a little expensive though so would like to know what the front baffle dimensions are (so i can cost it and decide)

many thanks
Gareth

muffinman
17-01-2009, 13:03
I see there are various emince 15s at vaying prices alpha-delta £35-£65ish
are these pretty much similar or is the power handling (200-400w)a major concern. I don't wish to sell my self short but if i don't need to buy the most expensive then that's a help.

Clive
17-01-2009, 13:18
Yes, that could well have been the reason, although it was interesting that it was happening on one speaker more than on the other... I think what we should perhaps do is for me to bring my kit to yours (everything minus the speakers) and see if it happens again. I think it's also partly to do with how they're being driven.

It's an interesting one for sure!

Marco.
Marco, it seems unlikely that a reflected bass wave from your Spendors would cause cone displacement on the OB bass. As you suggest it seems more likely that this is something to track down upstream. Was this a big cone movement, ie like a badly warped record can cause? Did it happen with CD too? I assume it wasn't continuous, just when music was playing, did it happen all the time music was playing? Valve pre and power amps when they go unstable they "motorboat", this is a low frequency beating, normally though you would hear this rather than only see it and it would be continuous.

Mike
17-01-2009, 13:36
Dunno what it is, Marco. Everything seems ok. Doesn't do it here at the volume i play at.
Might just be a reflection of the bass wave off the Spendors, which were right behind.

Don't worry. It's just the LF instability in Marco's rubbish old music centre! :eyebrows:

:lolsign:

Mike
17-01-2009, 13:39
Oh, I see Clive beat me to it.... Sorry.

Ali Tait
17-01-2009, 13:48
Hi Gareth,
Al will confirm I'm sure,but I think he used the Betas.I think the different models have different impedances and sensitivity.

alb
17-01-2009, 13:48
Clive.

It's just a noticeable cone movement on the full range drivers. These only have an Xmax of 1mm and normally don't move visibly on my system.
It's nothing like motorboating or the kind of movement you get with dc.

I'd expect this to happen if i was running them as full range, but they should be crossing over at 120Hz. Its not enough to concern me, but the fact it was more obvious on the left side just made me think.

Marco
17-01-2009, 13:59
LOL, Mikey, good one! :ner:


Marco, it seems unlikely that a reflected bass wave from your Spendors would cause cone displacement on the OB bass. As you suggest it seems more likely that this is something to track down upstream. Was this a big cone movement, ie like a badly warped record can cause? Did it happen with CD too? I assume it wasn't continuous, just when music was playing, did it happen all the time music was playing? Valve pre and power amps when they go unstable they "motorboat", this is a low frequency beating, normally though you would hear this rather than only see it and it would be continuous.


Clive, I'm sure Al will be able to describe it much better than I can, but I don't think it's as a result of what you describe above. The best way I can describe it is that the 'full-range' drivers (their response tailored to be used as midrange and high frequency units) were 'pulsing', or moving in a piston-like fashion, in time with the music and in conjunction with the bass cones, but on one speaker it was doing it significantly more (L/H channel) than on the other.

I'd be interested in your further thoughts on this. I basically put it down to my rather punchier and more powerful push-pull amp putting more bass energy into the drive units than normally happens with Al's SET amp, together with perhaps the slightly more capable source components reproducing a stronger 'musical signal' and thus both combining to drive the speakers much harder than normal with Al's equipment.

It's worth noting also that at no point was there any audible distortion and that the speakers could quite clearly be driven very loudly and with seemingly endless available headroom.

That's why I'd like to take my gear around to Al's and see if the same thing happens in a different room and without the Spendors in situ, and also compare the effect of Al's source and control components to mine using his speakers. The only way to ascertain what's happening is to remove as many variables as possible.

Marco.

aquapiranha
17-01-2009, 14:09
Perhaps the filters are not doing the job properly? I would imagine that may be a possible cause, and as for the effect being greater on one side that may simply be down to to the fact that bass is considerably less directional than mid / treble energy and therefore it would "sound" like the problem is coming from both channels? all hypothetical of course.

Clive
17-01-2009, 14:17
Perhaps the filters are not doing the job properly? I would imagine that may be a possible cause, and as for the effect being greater on one side that may simply be down to to the fact that bass is considerably less directional than mid / treble energy and therefore it would "sound" like the problem is coming from both channels? all hypothetical of course.
Pistonic movement sounds like motorboating, it's possible that any instability is very marginal and only happens with music applied. However it does seem that what I'll call the wideband units were receiving a bass signal they don't normally see. Am I correct in thinking the widebands have no crossover or at least no low freq filter? That should be best for sonics. Possibly bass that you were playing (loud, yes?) was showing up as wideband cone movement but the driver either cannot audibly produce bass at low freq or at only a very low level.

Marco
17-01-2009, 14:28
However it does seem that what I'll call the wideband units were receiving a bass signal they don't normally see...


That would be my subjective assessment of the situation. Perhaps 'pistonic' was the wrong word to use to describe the type of movement that occurred.

Marco.

Mike
17-01-2009, 15:13
Your system is broken.

Worry I tell you. Worry!!! :mad:

sastusbulbas
17-01-2009, 17:24
Any pics of these £200 speakers?

Mike
17-01-2009, 17:33
Earlier in the thread. The white ones.... I think!

Marco
17-01-2009, 18:43
Steve,

Like Mike says, they're the white ones posted earlier :)

Marco.

alb
17-01-2009, 18:54
Clive.

The wide band drivers have a capacitor to cut the bass response below 120Hz. They can sound a little congested in the bass region, when run without these.

We witnessed the same effect when i took them to Ians(another gutsy push pull amp). So i don't think it's anything to worry about.

I have a spare pair of these drivers in the shed, so i'll do some comparisons, and also check the caps again.

I'll post further details of the speakers later, for anyone who is interested.

Marco
17-01-2009, 19:02
Hi Al,

I see. I don't remember that happening there at all :scratch:

You didn't make any comment on it at the time either, as far as I can remember...

Not to worry, but if it is simply the 'push-pull factor', your visit has inadvertently told me something quite significant about SET amps.

Marco.

Clive
17-01-2009, 19:04
Al, if it's not a problem for the way you listen then don't worry about it. Just enjoy!

Marco, your needs seem different....Atlas uses two 12-inch widebands and no crossover, now we know why! I suspect that Al has a great speaker (possibly regardless of price) that fits his needs. Your needs probably require greater power handling.

Clive
17-01-2009, 19:07
Not to worry, but if it is simply the 'push-pull factor', your visit has inadvertently told me something quite significant about SET amps.

I don't think it's PP vs SET it's more about power and loudness. Ok PP is generally more powerful than SET but that's all. Try some of the powerful SETs with a couple of thousand volts driving the power valve, you'll get the same effect.

muffinman
17-01-2009, 19:09
I'll post further details of the speakers later, for anyone who is interested.

That'll be me then - i look forward to it:gig:

John
17-01-2009, 19:23
Today I listened to some Open Baffles kit speakers that would cost £2000 to build and put into the system; they were not as good as my home speakers came away very disappointed but know done right Open Baffles can create magic just cannot afford to go down the Atlas route

Clive
17-01-2009, 19:38
Today I listened to some Open Baffles kit speakers that would cost £2000 to build and put into the system; they were not as good as my home speakers came away very disappointed but know done right Open Baffles can create magic just cannot afford to go down the Atlas route

What about Prometheus? You could hear some at Vic's Watford "studio".

John
17-01-2009, 19:56
Yes hope to borrow Vic's Prometheus soon as he kindly offered to lend me his so will even hear in my own system

Marco
17-01-2009, 20:02
I don't think it's PP vs SET it's more about power and loudness. Ok PP is generally more powerful than SET but that's all. Try some of the powerful SETs with a couple of thousand volts driving the power valve, you'll get the same effect.

Yep, I get what you're saying and don't doubt that's true.

When things like this raise their head I just find it intriguing and like to get to the bottom of it, that's all :)

Marco.

alb
17-01-2009, 23:42
Simple Open Baffles. The details.

For each speaker.
You will need....
Two panels cut to 38"x10"
One panel cut to 38"x16"
Two lengths of piano hinge, if you want it to fold up for space reasons. Otherwise, make the front panel 26"x38" instead.
I used 18mm MDF because these were originally only prototypes. Never felt the need to change much. However, thicker is thought to be better.

Drivers.
I use a pair of Audio Nirvana 8" STD full range drivers from here...
http://www.commonsenseaudio.com/

Bass drivers are Eminence Beta 15 from Maplin.

Drivers are mounted at centres of 6" and 22" when measured from the top of the 38x16 panel.

I have a 150uF Mundorf capacitor in line with the full ranger, along with a 2.2ohm 7watt wirewound resistor.
http://www.hificollective.co.uk/components/mcap_bipolar.html

Something like this in line with the bass driver.
http://cgi.ebay.co.uk/Subwoofer-filter-12dB-120Hz-Low-Pass-Filter_W0QQitemZ130279502082QQcmdZViewItemQQptZUK_ ConElec_SpeakersPASystems_RL?hash=item130279502082&_trksid=p3286.c0.m14&_trkparms=72%3A1300%7C66%3A2%7C65%3A12%7C39%3A1%7C 240%3A1318


http://i27.photobucket.com/albums/c164/alnewall/OBs033.jpg

evozero
12-04-2009, 12:54
Hi All and Al.
These speakers look fantastic! Just the sort of project I am looking to try.
Is anyone else interested in pooling our resources to buy the components. It could help save on shipping, especially the Audio Nirvana's from the states?
Al, are the Eminence Beta 15 Speaker 8 Ohm with model number EM124G1. The Maplin pictures look different?
Cheers
Ian

SteveTheShadow
12-04-2009, 16:24
Hi Guys,

I'm very very late to this thread but having heard both Steve's and Al's baffles, I have to say they are excellent sounding devices. I was so impressed with them that last year I set about designing and building my own.

Whereas Al's and Steve's baffles are passive, mine have active bass. The bass unit is an Eminence Delta 12, the full-range unit is a Goodman's Axiom 401 and the uppermid/treble unit is a Fostex FE108EZ 3" driver.

The passive section is driven from my Jack Elliano inspired PX25 Direct coupled ultrapath DRD amp.

My room is only 12 x 12 feet x 9ft high yet these speakers produce the best sound I've ever had in that room, despite being, like all open baffle full range speakers, quite large.

Here's a pic of them in situ.

http://homepage.mac.com/scress1958/.Pictures/genview.jpg

The main drivers:

http://homepage.mac.com/scress1958/.Pictures/bafflerear.jpg

and the various inputs

http://homepage.mac.com/scress1958/.Pictures/baffleside.jpg

Active bass section is fed by the red/black section of the Linn K400 bi-wire cable. Passive section fed by the other half of the cable into the bottom Speakon connector.

Steve

John
12-04-2009, 18:08
Nice baffles Steve

Ali Tait
12-04-2009, 20:34
Look forward to hearing them Steve.

evozero
13-04-2009, 14:37
Hi All,
Those speakers look great Steve, maybe a little pricey for me at the moment. You guys know an awful lot on this forum, so i wanted to ask a few questions about OB speakers.
The only large driver speakers i have heard recently were really expensive, with fancy tweeters powered by expensive amps. I love the bass slam and extension with a walk around sound stage, i guess this is what i am trying to recreate on a budget. I am hoping to buy a Chinese SET to power them. Would speakers like Al's do this in my room? Or should i be looking at a different DIY design?
I read the OB articles in HFW and i'm a little unsure if they will suit my room.
My room is only 14ft X 12ft 9ft ceiling, with speakers against the rear wall and 3ft from side walls. I have put some pics in the gallery to give you an idea.
I am really enjoying tapping you lot for answers, i do feel like a bit of a leech asking all these questions. But i have totally given up going to dealers, the last time i set foot in one and told them i was using valves and vinyl "why would you do that, your missing so much resolution" Final straw, DIY all the way!
Cheers
Ian

SPS
13-04-2009, 21:01
Ian, there are no straight answers, bigger rooms/ smaller rooms /expensive drivers/cheap drivers
with drivers and rooms.. bigger is better for bass
but that should not put you off a little diy in the open baffle dept

baffles are cheap and easy to make and you can play to your hearts content and if you dont get on with them you can usually recoup your outlay..
peter comeau's hi fi world open baffle ramblings where inspired after listening to my speakers at a diy meet.. he had not liked baffles until that point as far as know.. and he is stuggling to replicate mine, as some of my speakers used are vintage types and modern speakers are not the same.. without spending alot of money
there are various of schools of thought with open baffles, and always some comprimises.. as with all speakers?

the emmience drivers are a good and cost effective way of building open baffle speakers..
a 15"er.. linked with a full ranger of approprate quality and effeciency can provide very good results.. Al's are a prime example

i dont know where you are based but there will be quite a few speakers at our diy meet in june over on the audio-talk forum, you can get much more of a handle on what they do sound wise
i would forget the chinese amps...unless your a competent repairer they all seem to need sorting in some way

if you can wire a plug, use/own a multimeter and solder.. (that was my level before i built my first valve amp...) i would say building a wd kel84 is a much better bet.. and you will learn how easy valve amps are to build..

the main issues with baffles is the ability to move enough air in the bass..

most that build open baffles use the higher efficiency drivers, these have less forward and backwards cone movement, which is fine except in the bass, where they dont move enough air, coupled with the fact that part of the sound wave is cancelled due to the baffle

so there are a few choices.. to live with less bass, to add extra higher efficiency bass drivers( thats sort of been my way with a 12" and 15" per channel), add some form of Eq , or to add a seperate amp to a lower eff bass speaker..to bring the bass volume up.
the issue with the last method is a low eff driver is used, it sounds fine on its own but the higher effeciency mid/ treble unit will show its lack of quality up...
steve has got over that by using a reasonably efficient bass unit and a seperate amp
i too am looking forwards to hearing steve's at our next get together.

the real skill for building open baffles is in selecting the drivers, getting that right can make things easy so using a known combination is a real advantage..

hope thats some use
steve

alb
13-04-2009, 21:10
Ian.

The Eminence Beta drivers at Maplins seem to be the same, they might have changed the colour on the back.
Mine are Beta 15A 8ohms and the specs look to be the same, though the price has taken a bit of a hike. You might find them cheaper elsewhere.

Whereabouts in the world are you?

I drive mine with 4-5 single ended watts, but as Marco will testify, they respond well to a bit more power.
Mine fold up so they fit neatly in a space against the wall when not in use, but i drag em out into the room a bit for listening.
I can't remember the last time i set foot in a dealers showroom, maybe i bought some phono plugs or something before Maplins arrived in Chester.
Don't look back.:)

SteveTheShadow
14-04-2009, 14:09
Ian

Looking at the size of your room, you would do well to use a bass driver with a lower Q. The Eminence Beta 15 has a total Q of around 0.5. My Delta 12s have a Q of 0.45.

The reason for this is that they will roll of rapidly below resonance; not ideal in a larger room, but absolutely spot on for a small room. You compensate for the rapid roll off at the bottom by placing the baffles closer to the wall to get a bit of room gain.

Mine are about 2 feet out from the rear wall of my room, they go low and more importantly, do not set up room boom. Something like the Eminence Alpha 15 with its Q of 1.26 would have been awful in a small room.

Mine use active bass only because I had two plate amps available by cannibalising my old pair of subwoofers. Delta 12 8 ohm bass drivers have big magnets, so they are well damped in themselves. The plate amps therefore have no trouble controlling the cones in free-air, giving a tight, firm and fast foundation below the Goodmans full ranger and the Fostex HF driver. In other words they can keep up with the main drive units without slowing things down. The bass units are 98dB/W efficient so they match the efficiency of the Goodmans driver.

As Steve has hinted, a low efficiency driver on bass duties would have compromised the bass performance to an unnaceptable degree.

In a large room, my baffles might very well sound bass light. I haven't yet tried them in such a space, so the next meet will be interesting.

Steve

evozero
14-04-2009, 14:16
Thanks al & Steve for your replies. The first thing about Al's design was the cost, but if they are not suitable then i should put the money elsewhere. I was looking around on other uk hifi forums recently and did see mentioned some horn loaded speakers, i think fostex based. But i have gone dizzy looking for it again. I think Al's were at the same meet, any ideas? Thank you for inviting me up, i would love to come, but i just sold my car and South east London might be too far to hitch! Are there any meets around London?
I am really itching to build some speakers that will kick commercial butt and not cost a fortune, so any more suggestions would be gratefully received.
I am currently running some cheap Chinese valve amps, so i am aware of their shortcomings. I heard some expensive SET's at an audio jumble and loved the sound, so trying to get close on a budget.
Thanks again
Ian

John
14-04-2009, 18:35
Once I get mine up and running you are more than welcome to hear mine

evozero
14-04-2009, 21:47
Thanks John and other Steve,
I just asked the other half for the go ahead, Yes!
I found the Eminence Beta 15 for £45, so will order them tomorrow, Should i pay a little extra for the Audio Nirvana super 8 or stick with the Standard? Gonna ask my mate in the states tomorrow to order them for me.
Really looking forward to building these, so any more tips?
Cheers
Ian

alb
14-04-2009, 23:11
Ian.

The Super 8 is apparently more up front sounding, which is perhaps better if you have a heavily carpetted and well furnished room. The STD 8 is fine for me because i have wooden flooring.
Having not compared the Super 8, it's difficult for me to judge either way.

If you have any reservations you can contact David Dicks at Commonsense Audio. He was quick in responding to my questions.
Either way the drivers will take a few hours to loosen up, before you hear what they can do.

Tip.
Once you have ordered the drivers, get everything else organised while you are waiting for delivery. Then it's just a matter of fitting them when they arrive.

Marco
15-04-2009, 06:57
I drive mine with 4-5 single ended watts, but as Marco will testify, they respond well to a bit more power.


Err, just a little bit! Freakin' awesome on the end of 30W Class A valve power :fingers:

Ian, just build these speakers - it's a no-brainer!

Marco.

SteveTheShadow
15-04-2009, 12:23
I would agree with Marco.

Looking at your room size on your system pics thread, Al's baffles with the Eminence Beta 15 bass units would be ideal for your room. You would not need to have them too far out from the rear wall (due to the the low Q I talked about) they would not intrude on the domestic environment and would sound awesome to boot!

As Marco says, it's a no-brainer.:)

Steve

evozero
15-04-2009, 13:18
Hi All,
Right then, i have sent the money to my friend in the states for the AN Super 8's this morning. Also ordered the Beta 15's from Amazon, but just had an email to say the supplier has cancelled due to stock not available. Boo! So if anyone knows a good source please let me know. Maplin are way over priced.
Just got back from the wood yard with some option on the baffles;
8X4 18mm chipboard £17
8x4 18mm plywood £45, 25mm £63
8x4 18mm Latvian birch £65
8x4 18mm spruce / pine £33
8x4 18mm MDF £24 25mm £34
I would prefer £35 options unless you lot think its worth the extra.
No charge for cutting but they cannot do the holes for the drivers. I don't have a router so if you know of any solutions? Cant afford to buy one and jig etc.
As you can see I am very keen!
Many Thanks
Ian

evozero
15-04-2009, 15:59
Another update; Found the Beta 15's here www.bluearan.co.uk good to deal with, had the 120hz filters as well. Received an Email stating dispatched order 20 mins after placing, impressive.
Cheers
Ian

alb
15-04-2009, 21:24
Well, choice of wood depends largely on how you want the finished article to look.
I'm not sure how much Open Baffles are influenced by the material they are made of.
Decent ply can be stained to good effect, whilst MDF is better suited to paint in my opinion.
Thicker is probably better, but also heavier if they are to be moved around.

Speaker apertures can be cut with a jigsaw and a bit of care. Measure the diameter carefully. Too big a hole and you will have problems with the mounting screws. No need to rebate the drivers. Whatever the material, make sure to drill pilot holes for all the screws to avoid splitting the board.

The Grand Wazoo
15-04-2009, 22:26
I know a little bit about wood and the products thereof - I'm in forestry management & have spent some time selling timber to instrument makers.

For sound quality I would favour the nearest thing you can get to real tree - the denser the better. MDF is used by speaker manufacturers because it's cheap, usually flawless and machines & finishes well - don't be fooled by anyone on this.

But for best finish for least effort you should follow the speaker manufacturers lead!

Personally, I'd go for the Latvian birch - it will be very slow grown and, therefore, by far the densest of the options you mention.

Hope this helps

evozero
16-04-2009, 12:11
Thanks Guys,
I appreciate your input.
I now have possession of the Beta's and ordered the rest of the parts.
Just come back from the wood shop, bought 18mm mdf to keep the costs down for now.
Al, may i ask what diameter hole you cut for the Audio Nirvana, i wont get this for maybe a week or two. Might as well get the baffles finished and waiting so i can just drop them in.
Cheers
Ian

alb
16-04-2009, 16:49
Diameter of cutout for STD 8 was 71/2 inches(7.5) according to the plans that Commonsense Audio sent me. I wouldn't go any bigger than that.
Presumably the Super 8 is the same.

evozero
21-04-2009, 11:14
Just a wee update; I have built the speakers and have them burning in while waiting for the Super 8's. They should be with my friend in the US today.
http://i732.photobucket.com/albums/ww322/evozero7/P1050498sm.jpg
Just need to drop them in and mount the crossovers. Going to use the fabric off the panels behind and recover the panels with plain black cloth. Its a really good way of keeping partners happy " You decide dear "
ATB
Ian

alb
21-04-2009, 18:00
Looking good.
You might find the output of the two sets of drivers varies a little during run in. I think i changed the resistor value three times in the first few weeks, until i eventually settled on whatever i'm using now. The AN drivers changed in character quite a bit in the first few days, and then seemed to get slowly better and better.
Remind me what amp you have. I guess most amps will run them in faster than my 5 watts.

aquapiranha
21-04-2009, 18:25
Fantastic! I hope to start mine soon, but will need to wait till I get enough readies as I plan (hopefully) on using an active crossover...

evozero
23-04-2009, 08:26
Hi All,
Al, i am running in the Beta's on my Sony integrated, cushions, blankets and the radio on all day. Has already made a big difference to the bass output.
but will use my little Wave 8 mono blocks full time. They are 8 watt PP jobbies, but as soon as funds allow i will go down the Chinese SET route. either the Audioromy 813 or Mr Liang 845. Tracking Super 8's to my mates house today, fingers crossed!
Cheers for now
Ian

Ali Tait
23-04-2009, 16:39
Whereabouts are you Ian? I have both of those amps so perhaps we could arrange a meet so you can try both the amps with your speakers sometime.

bonneville
24-04-2009, 09:32
Hi Steve
What you need to do to raise cash is sell you Decware to someone who will treasure it Hint Hint.
Vinnie

aquapiranha
24-04-2009, 09:38
Hi Steve
What you need to do to raise cash is sell you Decware to someone who will treasure it Hint Hint.
Vinnie

The veiled hints had not gone un-noticed Vinnie. the thing is though I would need to sell the pre at the same time or I would be less likely to sell it on it's own!

but yes, the thought had ocurred to me, as I would then be able to get an actice crossover (maybe) and two or even possibly three audiosector amps to sort out the OB's...

Hmmmm :scratch:

bonneville
24-04-2009, 09:55
Hi Steve
I have just posted my Lowthers for sale so who knows maybe a bid is comming

Vinnie

aquapiranha
24-04-2009, 09:56
You are getting rid of the Lowthers? I thought they were great! waht are you going to use instead?

evozero
24-04-2009, 10:12
Hi All,
My Super 8's are to be posted today. Only a week or two wait until i hear what OB's are all about.
Ali, i am in Catford, south east London. You would be very welcome to bring your amps round, can i twist your arm to make this possible ;) Where are you based?
Cheers
Ian

bonneville
24-04-2009, 10:30
You know what I have got

Vinnie

evozero
01-05-2009, 10:02
Hi All,
My super eight have landed!
Ok, i fitted them and had a quick listen, very harsh, but to be expected. So i let them running in for six hours and had another listen, still harsh and very bright. I am guessing they need a few days use before any serious decisions are made.
Another initial problem, the output from the super 8's is about double the level of the eminence, makes the OB sound very bass light. So i used my sony integrated amp driving the eminence and my valve amps on the super 8's, this way i could raise the bass levels to match.
Does this sound normal to you guys?
Long term i want to use just one amp, but i don't know how i adjust these levels?
I checked the wires are connected in phase, and the Super 8's have the capacitor and resistor in series on the positive binding post.
I am also assuming i am doing something wrong due to newbie status!
Cheers
Ian

Stratmangler
01-05-2009, 12:07
Your resistor probably needs to be connected across the speaker terminals.

Chris:)

technobear
01-05-2009, 12:26
Hi All,
I checked the wires are connected in phase, and the Super 8's have the capacitor and resistor in series on the positive binding post.
Ian

If the cap and resistor are in series with the speaker then that is a high-pass crossover and you are using your super-8 as a tweeter :lolsign:

If the cap and resistor are meant to be a zobel network to even out the response of the super-8 then they should be in series with each other and in parallel with the super-8.

What are the values of the cap and resistor?

evozero
01-05-2009, 13:35
Hi again,
I was going from the photo and of Al's in post 66 of this thread. Same value components.
I think the idea was to cut some of the lower frequencies to the Super 8's. But this is my first speaker build, so probably just me getting it wrong.
The eminence have about 45 hours use and the Super 8's now have about 12.
Thanks for your help

Stratmangler
01-05-2009, 13:48
Posting a piccy might help.

Chris:)

evozero
01-05-2009, 14:33
Here you go;
http://i732.photobucket.com/albums/ww322/evozero7/P1050510resized.jpg
ATM I have the two drivers completely separate, and on separate amps. Before I had the input on the low pass filter connected to the binding posts and the output to the beta 15. And the full range as the photo, negative straight to the negative on the Super 8, the positive goes to the cap and res then binding posts.
Is this ok?
Thanks

Ali Tait
01-05-2009, 15:21
Hi All,
My Super 8's are to be posted today. Only a week or two wait until i hear what OB's are all about.
Ali, i am in Catford, south east London. You would be very welcome to bring your amps round, can i twist your arm to make this possible ;) Where are you based?
Cheers
Ian

Sorry Ian,just saw that I didn't reply to you.My apologies.London is a bit far away I'm afraid! I'm in Leeds (Sometimes,but where my main system is) and Dunfermline (most of the time) There are some DIY meets coming up.The first is at Eggborough Power Station social club,I think on the 16th of June.This is near Doncaster.There is another in September,a 2 day event at Owston,again near Doncaster.Check out the WD and Audio-Talk forums for details.If you can make either of these,I can bring the amps.Al usually brings his system,so you could get a good idea by playing my amps through his baffles.Otherwise,if you're up north anytime,get in touch.

alb
01-05-2009, 16:10
Ian.

From what i can see, you have got it right. 150uf and 2.2 ohm resistors.
I would go back to just using your tube amps and try some higher value resistors to attenuate the ANs a bit more. My ANs were in two different cabinets before the open baffles, and did sound rather harsh for a while.
You are using 2R2 resistors now, which is the same as i use with fully run in drivers.. You could try 3R3 or 4R7 to see if they have the desired effect. When the ANs settle in a bit you should be able to revert to 2R2 or thereabouts. It's early days yet.

technobear
02-05-2009, 01:02
The driver will take several hundred hours to fully run in. It will test your patience in the meantime.

Also worth noting that you have a noise and harshness inducing white ceramic sound coffin in series with your AN driver. The sound will improve greatly when this is replaced with a decent resistor, e.g.

http://www.hificollective.co.uk/components/mills.html

:)

alb
02-05-2009, 07:05
Chris.

The white coffins are ok. Mills are a bit pricey to be experimenting with different values at this stage. Expect to buy several pairs over the next few months.
I've been using my speakers for nearly two years now, and have tried different types of resistors. Maybe its time to try some Mills again now i've settled on a permanent value. Didn't notice much benefit last time.

evozero
06-05-2009, 13:02
Hi All,
Ali, thanks for the offer, but you are right. We live a bit too far apart. Even the DIY meets are too far without a car. Are there any London meets?
The speakers.
http://i732.photobucket.com/albums/ww322/evozero7/P1050517res.jpg
I have them nearly finished, covered but awaiting run in and crossover mods.
Did quite a lot of listening over the weekend,Wow! They do an amazing job of disappearing , and no box colouring the sound. Still using two amps to balance the sound, I don't mind for now.
But before I start changing components I would like to understand a little more;
So the 150uf just cuts the bass frequencies to the Super 8 to lighten the load and allow it to focus on upper and mid frequencies, and the Resistor adjusts the output level compared to the Beta 15, is this about right?
Cheers for now
Ian

alb
06-05-2009, 16:25
So the 150uf just cuts the bass frequencies to the Super 8 to lighten the load and allow it to focus on upper and mid frequencies, and the Resistor adjusts the output level compared to the Beta 15, is this about right?

Yes, thats how i understand it, and also how it seems to work in practice.
Depending on which speakers you have been using, it may take a while to adapt to the sound from these, quite apart from the running in process.

Marco
06-05-2009, 19:06
Absolutely, Al - and you also need good quality, 'even-handed' valve amps to drive them. They are very musical sounding speakers, but ruthlessly revealing (as are all OBs)!

Marco.

Ali Tait
06-05-2009, 23:21
Indeed.And if you think thet sound good now,just wait till the drivers run in....

evozero
14-05-2009, 19:14
Hi All,
I thought I would check in and give a progress report, and ask a bit more advice ;)
I have another fifty hours on them now, and until today still running Bi Amp so I can adjust the levels between the drivers. Valve for the super 8's and my Sony solid state for the beta's. I am so impressed with them, the lack of box colouration makes such a difference. The way they let you hear every detail and how each mix is different, very revealing.
My only issue is matching the output's, so earlier I connected them to the valve amps only. The super 8's were still way too loud, so i added more resistors in series to bring the level down. I got up to 23 Ohms before running out of 7w's type. So I'm off to Maplin tomorrow to buy some higher values. The balance was getting close to the Bi amp levels I set, but I am worried something is wrong or the super 8's are very different to Al's std 8's. Or that they just require a much higher value resistor.
I cant see more running in will affect the output levels so much, the harshness yes.
What do you guys think?
Cheers
Ian

alb
15-05-2009, 06:56
Ian.

Sounds like something is not quite right here.
I wouldn't buy any more resistors just yet.
The output of our ANs is apparently the same. No one has ever said that mine sound like the description you have given. So there must be something different.

Do you notice any difference when adding these resistors?
Could you post a sketch of how yours are wired, so we can at least confirm that we are talking about the same thing.

If all else fails, i'm prepared to send you my spare pair of well used AN drivers for comparison. Quite frankly i'm puzzled at the mo.

evozero
15-05-2009, 15:35
Thanks Al,
I have the layout as below, running with a 4.6Ohm resistor for now. I did notice the levels coming down the larger the resistance. Then Something dawned on me, you had your AN's in two cabinets before the OB. I am assuming you used them full range? Mine have only ran with this configuration, with the capacitor filtering the low frequencies. Maybe they haven't really run in because of this. So now I have just the super 8's running off the sand amp with no capacitor or resistor covered with blankets, playing roots manuva loud. This will hopefully loosen them up!
http://i732.photobucket.com/albums/ww322/evozero7/crossoverlayout.jpg

alb
15-05-2009, 15:51
Yes, there wont be a lot of cone movement above the cap frequency. Hopefully you've arrived at a possible answer. Fingers crossed.:)

evozero
20-05-2009, 08:11
Hi All,
I have been running the AN for at least eight hours a day, full range. The sound hasn't changed much. So ran both drivers off the Sony amp, with the tone controls at 0 the sound is thin and bright,with little bass. But if i turn the bass to +10 it is much better balanced. Does this point to the crossover, maybe the sub filter? I tried the Beta with out the filter but the whole sound was very muddy and unbalanced.
Either the Beta's putting out too little or the AN's too much, if that makes sense.
Are there any measurements i can take with my digital multimeter, the drivers or crossover components just to compare?
Thanks
Ian

Giant Haystacks
21-05-2009, 01:14
when i started out i got a peerless kit and then a scanspeak kit and then a ipl kit and then a volt home studio monitor kit and i think it is the wrong route to go down.
every time you want something there is an answer and you spend some more.
i think you would be better getting some 2nd hand well engineered speaker as it would cost a lot less

John
21-05-2009, 06:04
Ahh the dreaded upgrade path yes I can see how this could be quite expensive if you follow that path but if you go for a good open baffle design its amazing what you can achieve
I think another issue is you not hearing what the speakers will do in your own system and room and this plays an important to sound as well.
But i heard a few open baffles and some of them have sounded pretty good to my ears

alb
21-05-2009, 07:18
when i started out i got a peerless kit and then a scanspeak kit and then a ipl kit and then a volt home studio monitor kit and i think it is the wrong route to go down.
every time you want something there is an answer and you spend some more.
i think you would be better getting some 2nd hand well engineered speaker as it would cost a lot less


No, this is not the same thing.
We have two almost identical pairs of speakers, which are apparently making very different noises. We have to find out why.
The problem is that we are two hundred miles apart.

Ian.
Did the output from the bass drivers increase significantly when the filters were removed? I don't have any tone controls so comparison is difficult. What i can do later, is hook them up to an Arcam SS amp and see what they sound like.
I'll come back tonight when i've given the matter some thought.

evozero
21-05-2009, 10:49
Hi All,
Al, you are a true gent!
First thing I want to say is these speakers have massive potential. Running with two amps and the right material, they are breathtaking. I was playing my friend Metallica with the wick turned up, he couldn't believe how good it sounded. Incredible, his words.
There are two main problems;
My lack of knowledge, and having no car.
If any knowledgeable user in the London area could come and help troubleshoot, I can provide food, beer and wine etc :)
My problems may not even be with the speakers, it could be my systems shortcomings being ruthlessly revealed. Probably my impatience, i don't know.
I am grateful to the forum users for the advice and comments, I'm sure a solution will be found.
Al, the bass increased slightly when I removed the filters. But not a huge difference.
Thanks for now
Ian

Ali Tait
21-05-2009, 14:10
Full range cones on open baffes do tend to be very revealing,in fact more revealing than anything except statics to my ears.Having heard Al's on several occasions I can confirm how good they are,so it may be that the problem lies elsewhere if they are sounding so good with some material Ian.

evozero
21-05-2009, 15:43
Hi Ali,
They sound much better Bi amped to get the bass level about right. I have a valve pre with the volume on about number 3, The valve amps are mono block with no controls. My sand amp volume is on number 8. Then I have plenty of volume and bass power. I not sure what the levels mean as i don't know the input sensitivity of the amps.
My valve amps are push pull 8 watt. the sony 40w.
If i was using only the valve amps, the volume is very loud set to 3, but with no real bass output. If just using the sony, 3 is loud and if I turn the bass control up to 10 I get good bass. If I Bi amp I get great bass. I can even set it for too much bass.
Hope this makes some sense, I'm getting dizzy swapping it all about.
Cheers
Ian

aquapiranha
21-05-2009, 17:39
Great to hear you are happy with them, makes me want to start ine right now....but I dont have the wood yet! I have everything but - drivers, crossover, amps at the ready....

:doh:

SPS
21-05-2009, 20:49
Full range cones on open baffes do tend to be very revealing,in fact more revealing than anything except statics to my ears..


mmm.... static's can sound very good.. but it does depend on what your comparing them too....

steve

Ali Tait
21-05-2009, 21:01
Just what I've come across Steve.F'r instance,on Nick's OB's,there was very little difference between his DAC and my Audio Note.On my system (with his amp) there was a HUGE difference which showed up how much better his DAC is than the Audio Note.OB's would be my preferred choice,but for the fact that to my ears statics soundstage and image better(yes smaller sweet-spot tho),which is important for me,and also are more transparent IMHO.Kinda have to be I think,given the difference in mass of a driver cone and the mylar film in a static.YMMV. :)

The Grand Wazoo
22-05-2009, 00:39
Hi Ali,
They sound much better Bi amped to get the bass level about right. I have a valve pre with the volume on about number 3, The valve amps are mono block with no controls. My sand amp volume is on number 8. Then I have plenty of volume and bass power. I not sure what the levels mean as i don't know the input sensitivity of the amps.....

...........if I Bi amp I get great bass. I can even set it for too much bass.
Hope this makes some sense, I'm getting dizzy swapping it all about.


Can I wade in?
There is something really special about a mixture of valve & solid state power amps in the correct proportions & in the right system.

I used to use (& still own) a pair of SD Acoustics OBS's. The best incarnation of that particular system was with them being driven with a Radford STA15 on the mid-range & a Mark Levinson ML11 driving the bass & treble.

The soundstage was truly holographic, only bettered in my experience by well set up electrostatics - but this layout had proper bass. It was magical & I suspect that my Audio Research preamp was contributing a lot to the soundstage.

(For more on the OBS's, see this place: http://theartofsound.net/forum/showthread.php?t=2175&page=2)

evozero
22-05-2009, 10:51
Hi Chris,
Love the system pictures. The SD speaker have already caught my eye, but my partner said no effin way, too big and ugly. Just managed to get my OB's approved by using fabric of her choice. I think they look great, and now they are more of a feature in the room. Sarah also doesn't like the sony amp sitting on the floor making the place look untidy, but she likes the valves. So Bi amping is not a long term solution for me.
Cheers
Ian

Giant Haystacks
23-05-2009, 01:36
im just not convinced about diy speakers as i said in my youth i saved by going diy and ended up unhappy and poor
anyway some of my thoughts i can not live with lowther and il leave it there , someone was mentioning open baffle i think this is not a good job for the big 15 inch such as altec it would be impossible to control the cone as they can sound wolley because of this , with very tight amplification they can turn from a good pa sound to something very good
i have tryed a lot of the more modern crossoverless designs fostex and john blue they are critical at times it is a case of try and try againto get an answer
some of the speakers i like quad electrostatic 57, reference 3a de capo, klipsch horn, spendor bc1 ,spica tc50, allison cd6 i ultimately prefer the quad but i have no space at the minute all for now

alb
23-05-2009, 07:08
i can not live with lowther and il leave it there , someone was mentioning open baffle :scratch:

This whole thread is about.....................................OPEN BAFFLES.

I'm busy fitting new basin and bog in downstairs cloakroom (little cupboard under the stairs).
Plenty of time to think about this, but not very much in the way of answers yet.
Beginning to think that the point Ali made, might account for some of the issues.
Different gear, different ears, different preferences etc.

Also beginning to think from your descriptions Ian, that these speakers are perhaps nearly there, and not the sonic disaster that i originally thought i was dealing with.

Ali Tait
23-05-2009, 07:59
Well it was just the thought that having heard yours a few times Al,they are so transparent that small differences upstream will make a large difference to the resulting sound.Agreed also about different ears and preferences etc.After all,with the likes of OB's and statics,changing just say a resistor is makes an easily audible difference.Does to my ears anyway.

Giant Haystacks
23-05-2009, 18:27
(this whole tread is about open baffle) ,sorry aib , i was just trying to contribute my experiences with diy speakers, as i did not read all posts in depth and was going by the heading( how good can diy speakers really get)
well on the open baffle subject, i dont think 15 inch drivers are best open baffle as when you wind them up the cone is to hard to control , so that is my one opinion -haystacks

evozero
01-06-2009, 12:39
Hi All,
I had a few good listening sessions recently, and got a friend to sit and listen while I adjusted the output from the SS amp. We got to approximately the same level where we both thought the bass should be. Al, did you manage to try the Arcam SS amp with them?
Interested to see if you could draw any conclusions.
I am praying its not my amps that need replacing, Having lost my job funds are gong to be very tight.
Cheers
Ian

evozero
01-09-2010, 15:05
Hi All,
Just thought i would revive this old thread with an update, Just in case you had the same drivers and wanted to play.
I was running the AN8's and Beta 15's as Al had them for a good while, although i couldn't get the bass response without sticking with the sand amp.
That is still the case, but i have used a H frame for the Beta and small round baffle for the AN's. this was inspired by the GR research speakers, and had a lot of helpful input from the designer, Danny. Check Audio circle for more.
The H frame helped the Bass out a lot and the small open baffle helped the Dipole effect.
But they need to be at least 3ft from the rear wall to get the deep 3D imaging, my wife hates this!
So i leave them up against the wall when not in use, a compromise.
Let me know what you think.
Pics
http://i732.photobucket.com/albums/ww322/evozero7/OB2/dsc_0256resized.jpg
http://i732.photobucket.com/albums/ww322/evozero7/OB2/DSC_0654resized.jpg
http://i732.photobucket.com/albums/ww322/evozero7/OB2/DSC_0653resized.jpg

John
01-09-2010, 15:12
One of my friends uses casters to ovecome this issue and does not appear to have any sound issues because of this. Might be worth a try you can always remove if you do not like
I tend to agree about the diploe effect increasing if using a open back. For me one of the big differences is how better the mid bass is due to this.
By the way nice work

John
01-09-2010, 15:14
(this whole tread is about open baffle) ,sorry aib , i was just trying to contribute my experiences with diy speakers, as i did not read all posts in depth and was going by the heading( how good can diy speakers really get)
well on the open baffle subject, i dont think 15 inch drivers are best open baffle as when you wind them up the cone is to hard to control , so that is my one opinion -haystacks
I think you need to hear good 15" baffles
The scale and control is awesome. None of other speakers I had come anywhere close

Ali Tait
01-09-2010, 16:55
Very nice Ian!