I didn't mean don't try to EQ the important mid range but rather, IMHO the optimum strategy to do so is still open to discussion.
There's loadsa stuff here from Danley, Wavebourn & others some of which I agree with & some I don't. I'd dearly like to play today since we have the computing power to make something that sounds good. In da old days, we barely had enough computing power to investigate this.
Certainly, what NOT to EQ is as important as what to EQ.
eg "don't try to EQ -30dB dips."
but not everything is as simple as this.
Benjamin & Gannon's approach (used by Meridian) is to look at the Q of the resonances & try to get all of them below some sensible value.
Note this means EQing some High Q resonances. Peter Fryer's work shows there is no problem EQing certain High Q resonances. In that sense, they are 'linear' but I don't think that is the correct way to look at things.
Another approach which I'd like to try and which comes under "Loudspeakers as microphones" is B&O's by Soren et al. Here, each speaker acts as a microphone and the other is used to try and produce resistive loading at the first. If this is achieved, then the (acoustic) power into the room is flat.
Neither method looks at Frequency response at some point(s) but take a holistic view of speaker/room.
Having said all that, I've heard of some impressive demonstrations of Denis Sbragion's Digital Room Correction which uses a very simple strategy. And there's Audyssey & other commercial stuff too.
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Thanks for these JC. I'm now reminded I discussed Hirata with the Yamaha engineers when we were doing the AST project with them.
Do you know which version of the test your Hirata box carries out?
Anyone done a Hirata test on a simple 5532 circuit with +/- 15V rails? Should be good for 10Vp at least. Just something to compare to Blowtorch. It would be imposing on JC's generosity to ask him to do this unless someone has such a beast, is within striking distance of Canoga Pk and is friendly with John.
Personally, I find this to be the whole point of the exercise, of audio. Except I wouldn't use the word "imagination", it's that incredibly sophisticated mechanism sitting inside our skull decoding the sound wave information.
I have found that frequently the most highly engineered, developed speakers to sound just like that, speakers obviously reproducing a recording. Whereas, downright mediocre speakers can recreate a musical event, take you to the venue where it all happened. What's the difference? In the latter case the hearing mechanism has been "fooled" into taking on board the message the recording was intending to convey, it's accepted the auditory illusion.
And why the setup with the nothing speakers has done the job is because enough of all minor, irritating distortion artifacts have been attenuated to a point where brain no longer has to spend too much time trying to unravel the conflicting information coming in. This is when people say, I don't what it was, but the sound was "magic"! This translates to, my brain was able to accept the illusion of the recording ...
Frank
I prefer to think with the "acoustic power" point of view.
Directivity curves are as important than punctual point's ones.
There are any number of ways to distinguish clipping and crossover in an amplifier from the smooth non-linearity of a speaker. In any case we have another test where any number of modern high speed op-amps will show nothing just as Ron Quan found out.
Sampling an original signal, Sampling the same reproduced signal, synchonizing-them and comparing each sample bit by bit or the delta between each two adjacent bits..
Whatever is convenient and good for you JC.
Anyone with a 5532 lash up within striking distance of Canoga Pk today? It would be good to have something to compare with Blowtorch.
This itinerant beach bum hasn't read Ron Quan's paper and would appreciate it if someone could email him a (highly illegal copy.
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Thank you Wavebour for the tips.
Actually what I am pleased with the last 8 - 10 years is just being fooled ( I admit it) by omnis and dipoles.
Ricardo, I don’t know how difficult it is to set-up and work with this program but in the documentation section of this link, in Appendix A, the results shown made my jaws drop. (Still, the worst results were at freq. btn 200Hz and 2kHZ)
George
Frank, don't discount the possibility that the 'downright mediocre .. nothing speakers' are actually the better speakers.
In my obviously biased pseudo speaker guru book, this is one definition of a good speaker. You see this time & time again in Blind Listening Tests. Size & cost often has little bearing on good sound.
George, this is a very good program and I've discusses the strategies with Denis in the past. But it is a 1D solution to a 3D problem.
Absolute Listening Tests-Further Progress tells you how important this is.
I started in speakers while still in school and used to measure them with a home made oscillator on top of our garage with the mike on a step ladder at 0100 hrs cos the buses stopped running. When I started at Wharfedale, it was suddenly easy with anechoic, B&K bla bla to measure and make a speaker with flat response. Surely the best speaker in the world must result!
I then spent the rest of my life trying to find out why a flat speaker doesn't always sound good.
Many people with a passion for speakers have similar experiences. I had the same experience again when I started dabbling in Digital EQ.
But please try out the excellent DRC. The more people with experience of this the more people I can steal ideas .. I mean learn from.
That's true in one sense ... a key thing I do is to tweak all the obvious, physical problems in the nondescript tykes, and stabilise them; what I don't worry about is changing to better quality drivers, altering the circuit of the crossover, the sorts of things that just about everyone else worries about ...
Just played Bowie's "Heroes" at a good, gutsy volume, on what most people would consider ridiculous speakers for doing such, quite pleased with how they went ...
Frank
Hello kgrlee,
Have you heard the Duntech Sovereigns, whats your take on them. Do you have any favourite big speakers.
Were Duntech once in Adelaide .. about a decade ago? Their 1st order networks ring a bell.
I don't think I've ever heard a Duntech speaker properly. My favourite conventional big speaker is the Celestion A3 .. nearly as big as the Sovereign. But don't forget I've been a beach bum for more than a decade so have no idea what's good these days. I know the A3 is Unobtainium as are many of the ingredients (especially the cone material).
Then I know a lot about their tech. I didn't come to Oz to be a beach bum. It just happened. I visited them maybe 15yrs ago.
But I haven't heard any of their speakers properly. As a genuine Blind Listening Test guru, I can't comment on sound based on my prejudices of what's in or not in their speakers.
The A3 is similar in concept to the Sovereign if not in detail. ie they were designed to do well in similar circumstances.
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