Another interesting part is when he says he can predict subjective performance when things measure well, but when they have distortion is quite difficult to predict how it will sound like subjectively.
I think one reason for this is that most people who looks into the research in detail find little which makes them say "that can't be right". Or to make them think that something fundamental is missing. Hence why repeat the same work and come to the same conclusion?I have been looking for a science based alternative point of view or criticism of the work of Toole/Olive, just because I'd prefer to have more authoritative sources and not only one - but let's face it, reality is that there is only their work.
But I don't want to derail this thread into speakers, a positive thing is that regarding amps we know all that needs to be known since decades, certainly there is not shortage of research.
Quite- but I think what draws the most ire is when an O perceives an S as asserting the poorly measuring but euphonic AND EXPENSIVE bit of kit is "better" than the more humble but better measuring kit, with all the accompanying flowery narrative. Sometimes I think that assertion may not actually be there, the S is just raving about some kit they like.
Not scientific but very technical and coming from a well known mastering engineer and audiophile, includes observations by his assistant too.Look I have only just skimmed that article but if I read correctly this is just some of Bob's personal listening impressions, hardly scientific research
Not scientific but very technical and coming from a well known mastering engineer and audiophile, includes observations by his assistant too.
I think one reason for this is that most people who looks into the research in detail find little which makes them say "that can't be right". Or to make them think that something fundamental is missing. Hence why repeat the same work and come to the same conclusion?
That is the one I had in mind.Halcro by designer Bruce Candy. Halcro was an offshoot of his Minelab (the best metal detecting technology in the world) company.
View attachment 75678
Oh, none were inexpensive.
https://www.stereophile.com/content/mbl-reference-9011-monoblock-amplifier-measurements
This is one I had in mind. I seem to recall another from Accuphase just can't remember which model.
Another which was so low in distortion it was not clear the measurement gear was up to it. I recall it stood tall vertically (I think it was Australian). Had tons of power, but was something like $30k. Sorry, I'm drawing a blank on the name, but maybe it will come to me or someone will remember it.
All of which put into context how good the Purifi, Hypex and Benchmark designs are in getting us gobs of power at high fidelity for relatively little money.
Yes, but if I recall correctly, Archimago's test was more trying to see how much distortion was noticeable, the less the better, while Bob Katz's is in another direction, how much 2nd harmonic distortion is subjectively "better" to hide/mask other artifacts and "improve" sound. Interesting topic.This test can now be repeated by anyone with a desire and a PC to run my DISTORT app. Add any one or combination of harmonics to any music track and listen through your own system. Archimago recently completed an Internet blind test with various levels of distortion with nearly 70 participants, and the results are public.
I think you'll find this interesting:Forgot to mention this: https://www.audiosciencereview.com/...nechoic-measurements-community-project.14929/
Seems to me that there is no science telling me how sloped should be the in-room FR, and if I mess a little bit with Dirac/Audissey/Minidsp/Rew/etc. I can introduce differences in the FR that are in the order of many dBs with a touch...
Yes, but if I recall correctly, Archimago's test was more trying to see how much distortion was noticeable, the less the better, while Bob Katz's is in another direction, how much 2nd harmonic distortion is subjectively "better" to hide/mask other artifacts and "improve" sound. Interesting topic.
Interesting that you mentioned it, I was just re-reading this review about the Qutest yesterday.What Bob was testing is a somewhat unnatural distortion consisting of just a very large second harmonic. No device I know of (other than designed for just this purpose) produces just the second harmonic at 1% with no other harmonics added.
Interesting that you mentioned it, I was just re-reading this review about the Qutest yesterday.
View attachment 75685
PS: not that I chase this, my systems are all the lower distortion the better, but I try to keep an open mind on people wanting to add flavours of distortion, specially tube preamps.
True, his "recommendation" was:That's hardly a 1% second harmonic, more like 0.0001%
True, his "recommendation" was:
"I recommend a maximum level of second harmonic no higher than 60 dB below the fundamental at nominal level (mezzo forte), typically -20 dBFS. The sound of -60 dB second harmonic is pleasant to the ear and enjoyable to many listeners, but perceived as a bit thick sounding with some loss of detail. Probably -66 dB second harmonic is the ideal setting, as in our listening it produces an attractive, warm, three dimensional quality with no apparent loss of detail or other side effects on any amplifier we tried. With some musical sources and some listeners, we may have to further lower second harmonic."
So about -20 -66 = -88dB full scale (0.004%), right? Chord did not go fully on this but possibly half way. Point is: some people do like added distortion.
Anyway this is getting off topic. Bruno is a zero distortion oriented designer.
That's just an appeal to authority. Doesn't really provide us with any further weight of evidence. It's just an opinion of one guy, nothing more.Not scientific but very technical and coming from a well known mastering engineer and audiophile, includes observations by his assistant too.
Sure we shouldn't stop investigating. WRT frequency response the important bit is that the speaker is flat in the first place - anechoicly so that on axis is good. Remember what you measure in room is not what you hear. Sure different rooms will change the sound in different ways but people still recognise the "good" speakers regardless.Because in my view there are still things that need to be investigated. Let's talk about in-room FR, to simplify we know that there is consensus that anecoic FR should be flat and that in-room FR should also be flat but sloped down. But how much? Should it be +3dB at 20Hz and -3dB at 20KHz? Or +5 and -5? Now we enter again in the realm of subjectivity, in particular now with all the inexpensive ways we have to EQ our speakers. At the same time we are obsessing about the 0.5dB (audible?) difference between say a Ncore module and a Purifi one at 20KHz so we feed a perfect (within 0,5dB) signal to our loudspeakers and then we EQ their in-room FR to be down 3dB or 5dB at the very same 20KHz and dial in a couple of dB at bass frequencies according to what? To our subjective preference.
Is there anything more subjective that a target curve or a so-called Harman target curve?
Is there a Harman target curve for speakers? Or is it just the fact that in room measurement of an anechoicly flat speaker will show a downward sloping response?