Sure Ali, concert level (120dB) is pretty extreme. However, 90db to 100dB isn't that loud in the right room when there is minimal distortion.
It might be interesting to measure just at what SPl one does listen at.
Printable View
Sure Ali, concert level (120dB) is pretty extreme. However, 90db to 100dB isn't that loud in the right room when there is minimal distortion.
It might be interesting to measure just at what SPl one does listen at.
Indeed. I do actually have an SPL meter from work. Must try it on the system.
I have noted in the past I tend to listen at lower volumes than some fellow nutters. S' me sensitive ears innit!
Bear in mind the ‘average’ vacuum cleaner is rated at 80dB.
Also, for those with the systems capable of erm, well, the scale people tend to talk about got from big drivers and realistic listening levels and how our perception of loudness doesn’t quite match SPL and of course, one musn’t forget than many partners can bend an ear at 85dB no problem and after all what’s a stereo for if not to drown out the missus and kids……….
I’m just sayin. :eyebrows:
Something that has not been mentioned so far is the Damping Factor of amplifier and speaker. In fact it's hardly ever mentioned anywhere, considering it's importance, so could someone provide us with an explanation?
Ok, just dug the meter out and tested it with some Led Zep. I deliberately drove to levels louder than I'd use even at a party, and the highest I got was 102db (C weighted)
A normal decent listening level for me is 88-92db, having just checked.
Ah good man, got the right weighting as well. :)
More seriously, I'm looking at the 80dB to 90dB range and even at these relatively modest SPls I was trying to point out that a you may need rather more Watts than you might initially suppose when amp clipping and variations in loudspeaker impedance are properly considered.
If you want a system that is truly capable of trouser flapping bass and awesome "like live" reproduction you'll probably be needing a few more Watts than you might think.
I very rarely listen much above 80dB, mainly because the room self dismantles at much more. But, even at that kind of SPL, when clipping is taken into account and adequate headroom is allowed for enthusiastic transients, what initially seems an amp of adequate power output may fall to bits with just a teeny lil tweak of the volume control.
Yes agreed, you need plenty of headroom for transients. One good thing about OB's to my ears is that they seem more immune to room effects than box speakers, so you can play to higher SPL's before the room becomes a problem.
my speakers are around 102 dbs , 2 watts (around half volume on the px25 amp) plays around 105 db peaks, with the average sound levels, dependant on the amount of compression in the recording...usually around 85-95 dbs ,
there very little in the way of distortion at those levels, i find 2-3 watts enough for the largest rooms, 96 db speakers would need around 8 watts to do the same.
but then you are getting out of the league of the the very best amplifiers.
Yes, that's what prompted me to say that say 2 to 4 watts should be plenty for 102db speakers, having heard yours at Owston Steve.
I thought so Ali..
is funny how trouser flapping bass and watts seem to go together for many, its not my experence. even with open baffles
Aye, it's a different kind of bass methinks. If you like it and get used to it, nothing else will do.
Because it's not as important as some think, I guess. I wish I could provide the quotes, but a few big names in hi-fi design and engineering have commented on how low damping factor is in their priorities.Quote:
Originally Posted by lewis
On topic: using my smartphone spl app, and not taking any weighting into account, I read peaks of 39dB and average of 29dB over a minute or so listening to soft jazz, mono, with a 40 wpc PP valve amp driving Tannoy Cheviots (about 92db sensitivity, I think). I often wish I could put the spurs to it, but certainly not at this time of night in a flat, and with two small kids sleeping down the hall. Measurement at the listening position.
I do my best be it in simple termsQuote:
Originally Posted by lewis
damping factor is a calculation between the impedance of the output stage of the amplifier and the speaker impedance.
so an amplifier with a low output impedance will give a better damping factor with higher impedance speaker.
that is why in the 50's 16 ohm speakers where the norm when quality was important with valve amps of the time,
back in the 30's many speakers where wound with very high impedance coils that dramaticly increased the damping factor and removed the need of output transformers, at the expense of fragility, as very few lasted long at all...but I have read that the sound quality could be very good.
todays SS amps can have a much lower output impedance, which can be considered important to control generally less powerfull drivers used in the modern speaker
there is also speaker self damping.. generally a speaker with a less powerful motor has less self damping, it relys on a stronger energy field from the amplifier to control the cone, and the speaker with the higher powered motor needs less help to control the cone.. in some cases much less
it is really nowhere as simple as that.. but it may help your understanding
Wow, thank you all, that was a whole lot to learn!
But getting back to real life decisions:
Does it harm to use higher power tube amps with high sensivity speakers? What are the negative effects of using a 2x12W or 2x40W tube amp instead of a 2x3W? Are the high power layouts prone to sound quality deficiencies?
Thanks for your reply Steve, time for a bit of research!Quote:
Originally Posted by SPS
i've borrowed this quoteQuote:
Originally Posted by nightyy
Quote:
“To raise the performance of a single triode amplifier above the crowd it is necessary to optimize the design and parts quality used in its realisation. It is not enough simply to use triodes.” Kondo
the best low power amplifiers are expensive and can rarely be bought from the hifi shop...
the hifi shop/ internet will point you in the direction of the masses.. larger output amplifiers..
as most people do not understand what real 100+ db speakers can do matched with a high quality amplifier.. and if you knew, you would not be asking us daft questions.. best of luck...
steve
No harm but possibly may not be not ideal IMHO. For instance, I used to drive my statics with an Audioromy 813 SE which was about 35 w/ch if memory serves. Sounded very good on the statics, but less so on other cone speakers for some reason.Quote:
Originally Posted by nightyy
I don't think higher power automatically means inferior sound, it's all about the quality of the components and the transformers. Good ones are expensive.
Steve is right in saying that some of the very old triodes can sound very special, but unless you are in his fortunate position of having a large collection of such things, it could get extemely expensive making such an amp nowadays as NOS '20's and '30's triodes are seriously pricey items these days.
That's right: you can only tell the difference if youQuote:
Originally Posted by SPS
a) own "real" 100db+ speakers -> money
b) you own high quality tube amp -> really a lot of money
c) have already had experience with a lot of other expensive gear from the low db, high wattage camp -> even more money
So I guess it's save to say that most people simply cannot understand because of limited budget
For collecting experience higher power tube amps give the chance to try them with different speaker sets. For example I own three sets of speakers, I can test one amp with all three sets, maybe one combination is just the perfect fit. If I go at the task with a 2x3W amp I cannot really use my 90db speakers with them, and future speakers will have to forfill a minimum of x db at the least.Quote:
No harm but possibly may not be not ideal IMHO. For instance, I used to drive my statics with an Audioromy 813 SE which was about 35 w/ch if memory serves. Sounded very good on the statics, but less so on other cone speakers for some reason.
I don't think higher power automatically means inferior sound, it's all about the quality of the components and the transformers. Good ones are expensive.
I have just acquired a used Melody SP3 with upgraded tubes for 435€ incl. shipment, and am keeping an eye open for a used 2A3 or 2A3/300B amp:
http://www.ebay.de/itm/150829050914?...ht_1664wt_1142
sort of... the thing is there are good, and not quite as good, in everything, there are not to many places where one can hear qualitiy HE &quality SE triodesQuote:
Originally Posted by nightyy
so for many its taking a chance, as a DIYer, it different you start off with cheaper and build up, my first valve amp was el84 based, the 4 watts convinced me valves was better, but not in every way,
it took some time and experimenting to acheve the sound i now get, and i've spent alot of money on the way. the funny thing is when others listen to my kit some really like the sound, but not every one gets it,
buying any amp i would lean towards one that uses older valves that can be bought at reasonable prices, the 2a3/45 is an example,
I have a pair of 1940's 300a ..there is a marked difference in sound quality between them and all of the new production, but the cost and rarity are prohibative for most.
where as say globe px25 and px4 (they sound close to 300a/b) are more affordable and available, the amplifiers are not, and so mainly limited to diyers...
Just noticed that this thread has re-surfaced with lots of techno speak which, unfortunately, goes way over my head!!
Anyway, thought I'd update my original post from 2010.
I decided to go for a low cost introduction to valves and bought an ST25 valve integrated from Icon Audio coupled with a pair of their MFV6 standmount speakers (MFV = made-for-valves) having spent a fab day in David Shaw's wonderful demo room. During the intervening period I've got through a number of front ends both analogue and digital. I've also replaced the MFV6's with a lovely pair of Celestion DL10 Series 2 speakers aquired from BlackAdder, tried some Castle Chester floorstanders but returned to the DL10's.
I love where I'm at right now. I can't describe sound quality in audiophilic terms, suffice to say this combo is open and airy, sweet and relaxing, there's a supernatural quality which is difficult to define. I have room issues which spoil the bass frequencies but I'm trying to resolve these.
Whenever I'm tempted to do a little box-swapping I simply play music and chill!
A huge thanks to everyone who helped me on my way.
You might be pleasantly surprised how well a 35w valve amp will drive 90dB speakers, depends on the sort of load they present.Quote:
Originally Posted by nightyy
Indeed, Nick. My 30W (before it was modded to 50W) Class A P/P Copper amp drove my 90db Spendor SP100s for long enough, no problem, before I got into big Tannoys!
Here's a pic of me old Spends:
http://img641.imageshack.us/img641/7150/aosm06.jpg
No problem getting 'stupid' levels out of them with this chap:
http://img829.imageshack.us/img829/83/oldcopperamp.jpg
Unfortunately, there's a lot of bullshite written about what speakers valve amps can and can't drive!
Marco.
Marco, your room is smaller than mine I reckon (looking at those 12" bass drivers) :eyebrows:
Good for deep bass then, as room modes are out of the window :D
One day they will understand, they being non sheeple :cool:
Hi Mark,
The room ain't big, but she's perfectly formed... ;)
I totally agree with where you're coming from, regarding deep bass. The Spends could kick it out, bigtime, and I loved using them for years, but the Lockies took things into a whole new dimension!
Marco.
I'll be converting our spare room in to a dedicated hifi room this next winter,Quote:
Originally Posted by Marco
my issue is that it may be a little on the small side, at just under 15x10, my speakers are around the size of yours marco, so i'm hopeing it works ok, the room needs alot of work before i move in so unable to test beforehand, but i know your room worked very well.
so fingers crossed...
nicks 35 watt SE amp drove a pair of massive pair of low efficiency speakers at our last diy meet, filling a large room (around 60'x90')with nightclub levels ...
unfortunatey for nicks very, very clean and detailed sounding amp.. those big low effieciency speakers at nightclub levels was not so clean sounding at all, but still his 35 watts was so much better than the big ss amp used beforehand
cheers...
Just wanted to come back to report that I had an intermezzo with a PP Melody SP3 MkII (which was good, but did not make me happy), and now own a Alex Ederer 300B SE with Sophia Electric 300B/n valves, and that is just much more the real thing music wise: It just sounds right.
http://nachtrab.de/files/AE300B.JPG