ToSA lot actually (any vintage japanese brands and a few european). But not in the same league as DIY amps (some are clones of expensive commercial amps) or my own designs.
Who do you mean, we?
It's your business obligation to keep on denying now but it won't change 2015 event on Hydrogenaudio forum.
Vacuum valves, for all their faults, are naturals for running hot (cathodes at about 1000 K).
All good fortune,
Chris
All good fortune,
Chris
Attached FFT of various output currents of the same amp.Thank you Tournesol, I’m completely out of my depth here, but will continue to listen to what is being talked about.ToS
(I love LTSPICE: never the magic smoke ;-)
Attachments
Transfer function is modified in the low level area. Normally it should be a straight line, here it is bent for low levels, approaching quickly to zero. The result looks like a crossover distortion of a poorly designed, heavily underbiased class B amplifier.
Attachments
I think it would be a good thing to do. ABX or similar testing of files where it is just audible - what some would call ear training, and then ABX of music where it is pretty much impossible to spot would be interesting - so testing how easy is it to learn to hear such a thing. You'd need to reduce the distortion to more probable levels perhaps.
Just a thought.
I have an interesting one on speakers and music. If I listen to classical music on my £180 workshop speakers (Q Acoustics 3020) the music is very, very listenable. If I try to play jazz or pop through those same speakers I can hear straight away that they are not quite on the money because the speakers lend a slightly ‘boxy’’ sound to the music So, it seems our tolerance for acceptability of sound very much depends on the material we are listening to as well.
I’ve been to quite a few classical music concerts so I reasonably know what an orchestra sounds like. Same for jazz and rock.
NB the Q Acoustics are for the money very nice little speakers - my comments here are really with a very critical ear, so I don’t want to sound like I am knocking them
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I hope I don't come off as conceited when I claim I'm pretty smart in some areas, but pretty dumb in others, especially when this post is about the dumb part.
I just don't get the logic of smearing someone's posts by claiming the poster has commercial interests, even going so far as violating the rules by name-calling (shill, snake oil salesman). The smear-campaign seems to focus on members whose posts the smearer doesn't like, not all those with commercial interests.
If PoliticianA says "2+2=4" and PoliticianB says "2+2=5", is "never trust politicians" a valid or useful criticism of PoliticianB? What about addressing the math?
Is this the logic?
1 MemberA sells ProductB, but never mentions ProductB or his company here.
2 Unknown to DIYA members, ProductB doesn't do well in blind tests, either being indistinguishable from less expensive products, or being worse than similar products.
3 MemberA doesn't condemn ALL blind tests, only those improperly conducted, using unfamiliar terms and references that leave the hapless DIYA members uncertain and doubtful. Particularly, when someone's wife heard lifted veils somewhere using ProductB.
4 Ka-ching!
This logic is so convoluted that the smearer may want to consider a career as an FIR filter!
I remember the ABX thread on the other forum and skimmed it looking for "the evidence". A different member of that forum thought (no links or proof) he recognized MemberA, and wrote*:
Is this "the evidence"? Wow! Lock him up! Lock him up! Lock him up! Lock him up!
I know I'm dumb; please help.
Disclaimer: Although I've spent ≈35 of my ≈40 work years at universities and research institutes, the last few years have been funded by a for-profit company. They use industrial speakers and amps, and non-audiophile microphones and headsets. Their products cannot be used to play the customers' music without modification. I'm 99.99% sure no DIYA members have ever or will ever buy their products. My funding is unrelated to sales.
* I deleted MemberA's username, but I bet everyone knows who it is, and added the italics.
I just don't get the logic of smearing someone's posts by claiming the poster has commercial interests, even going so far as violating the rules by name-calling (shill, snake oil salesman). The smear-campaign seems to focus on members whose posts the smearer doesn't like, not all those with commercial interests.
If PoliticianA says "2+2=4" and PoliticianB says "2+2=5", is "never trust politicians" a valid or useful criticism of PoliticianB? What about addressing the math?
Is this the logic?
1 MemberA sells ProductB, but never mentions ProductB or his company here.
2 Unknown to DIYA members, ProductB doesn't do well in blind tests, either being indistinguishable from less expensive products, or being worse than similar products.
3 MemberA doesn't condemn ALL blind tests, only those improperly conducted, using unfamiliar terms and references that leave the hapless DIYA members uncertain and doubtful. Particularly, when someone's wife heard lifted veils somewhere using ProductB.
4 Ka-ching!
This logic is so convoluted that the smearer may want to consider a career as an FIR filter!
I remember the ABX thread on the other forum and skimmed it looking for "the evidence". A different member of that forum thought (no links or proof) he recognized MemberA, and wrote*:
Is this "the evidence"? Wow! Lock him up! Lock him up! Lock him up! Lock him up!
I know I'm dumb; please help.
Disclaimer: Although I've spent ≈35 of my ≈40 work years at universities and research institutes, the last few years have been funded by a for-profit company. They use industrial speakers and amps, and non-audiophile microphones and headsets. Their products cannot be used to play the customers' music without modification. I'm 99.99% sure no DIYA members have ever or will ever buy their products. My funding is unrelated to sales.
* I deleted MemberA's username, but I bet everyone knows who it is, and added the italics.
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Thanks Pavel
If you are doing listening tests of noise why not reference the ITU-R 468 weighting curves & seeing that we are much more sensitive to noise around the frequency 6 KHz where it peaks to +12.2 dB above the Fletcher-Munson (done with single tones) A weighted curves
A noise signal centred around 6KHz (not 4KHz as I posted before) should be perceptually maximised
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Sorry, PMA, but, really, it has nothing to do with the kind of music played.
It is just the well known mask effect.
Every sound engineer knows how it is difficult to have two instruments playing in the same time in the same bandwidth and get both easily distinguable. Like a male voice and a tenor saxophone. Or doubled instruments (voices, guitars).
Every hifi listener knows that crossover distortion is more audible at low levels, just because the distortion ratio increase (same distortion components/less original signal).
Your two files are interesting, I can hear in a (too much) obvious way the both effects of your distortions: the original signal, correlated harmonics that are situated upper in the bandwidth, and awfull IM situated under this last one, absolutely non correlated, just like an independant parasitic noise added.
I believe this narrow bandwidth random noise test should be revealing to make the difference between analog magnetic tape and digital recording.
May-be the way to convince JC and some others of the benefit of digital ?
Here's a research paper that address some of the topics raised in discussions to date. "Psychoacoustic active noise control with ITU-R 468 noise weighting and its sound quality analysis."
It uses fMRI to objectively measure the psychoacoutsic response to the test signals rather than listening tests
As it says
From the conclusions
It uses fMRI to objectively measure the psychoacoutsic response to the test signals rather than listening tests
As it says
It examines three psychoacoustic metrics of the sound Loudness, Sharpness, Roughness & derives a preference based on these three which it call Pleasantness
From the conclusions
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Bonsai,
I find what you say is interesting. I only have one speaker and an eclectic taste in music. The speaker seems capable of playing back virtually anything, but quite often I will have to change the eq settings and the input/out levels of my iPod+preamp+poweramp, plus a change in how close or far away I sit when listening. Yes, this is a compromise, but I am listening to music, and if I can hear the structure of the sound, I will by default become immersed. Its like as if the speaker is a gigantic hearing aid, and quite often these changes are very subtle.
One of the very best things I ever did was to learn how to set up a guitar to give perfect pitch and intonation. How very subtle changes in pressure from the fretting fingers, combined with the dynamics of picking, can through a chord progression become convincingly emotional in terms of musical expression. I would say that for me, to play a musical instrument is excellent training for understanding the nuances of individual audio components within a playback system.
ToS
Pavel is cautious and conservative on what he is doing. 😉
6kHz is UHF for old guys like me.
George
Is is obvious, reason why the author of those endless harassments is in the ignore list of most of us.
His equally obvious obsession (to be polite) is interesting, assimilating professional design and snake oil.
Who would even think of attacking a doctor posting on a forum devoted to medicine ?
I would like to add that I don't think any one should be stupid enough to believe that any input he could provide in this thread to promote his products or his talent will increase his sales ;-)
Haha, surely not, 6KHz UHF
Have you tested your listening with noise centered around 6KHz?
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