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

[alb]

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.

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]

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]

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]

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]

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]

cheers john,
i'll take a long look at that over the w/e and see what sparks my interest.

[SPS]

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]

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!

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

Marco.

[twogoodears]

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]

http://www.phy-hp.com/English/Commun...ffle_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...