Sound Quality Vs. Measurements

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So, let me get this straight - people prefer tubes BECAUSE they have distortion?

Distortion is what helps them get more out of the source?

Holy Moly!

Nige, we need to design a "THD Enhancer" circuit.

An externally hosted image should be here but it was not working when we last tested it.


No. It will replace lost tones with the harmonics of other tones. Its cheating, and someone with your Golden Ears will immediately hear the difference. ;)

jan
yes, but average joe will notice "the tube sound with so bright treble"
 
SSL did have an enhancer for their mixing desks to sound like other desks ( SSL wasn't well respected for sound before David arrived ) . I am told it was close to being exactly right . Names are not used , experienced engineers know the sound of each desk type . Dave Mate is someone who seems to live happily with sound and measurements . I think when Neve some original parts are used from cannibalized ones ? SSL is two miles from me . Pure chance I know the guys .

My idea was to get John who worked with him ( my drinking buddy ) to cook something up . We would make a blameless amp . Output resistors and fake up the sound of various guitar amps . Trouble with John is he has no energy for anything that isn't zero distortion . His work conditions him . He is comparatively poor so it wouldn't harm him to have some money . He builds instrumentation amps , the body scanner people supply plenty of work .
 
Listening to my Panasonic TV recently I thought how good it sounded . A friend says it uses digital progressing to do that . Whatever is uses it puts to shame many box speakers . The drive units must be cheap
Simplicity is part of that - a relatively straightforward audio path will get a lot of key things right. My el cheapo LCD TV used as an audio system also demonstrates this - the audio is even pretty ratty compared to an old CRT Panasonic TV used in a bedroom, when just listened to as a TV; yet if all the right precautions are taken, and plenty of time taken to warm everything up properly it does a remarkably good job of getting the musical message through ...
 
Simplicity is part of that - a relatively straightforward audio path will get a lot of key things right. My el cheapo LCD TV used as an audio system also demonstrates this - the audio is even pretty ratty compared to an old CRT Panasonic TV used in a bedroom, when just listened to as a TV; yet if all the right precautions are taken, and plenty of time taken to warm everything up properly it does a remarkably good job of getting the musical message through ...

I agree . KISS ( Keep it simple , stupid . )

I heard an old valve recording on a modern film . The Panasonic shows in minute detail what is different .


My brother took the feedback loop off of an old Decca Bradford TV . He said to make dialogue easier to follow . He shaped the sound a bit and corrected the gain . PCL 86 I would guess ? In every way it sounded better , it escaped the TV better . When I asked why the engineers at Decca failed to do that he said " training " .

My valve amp I recently built was inspired by PCL 86 .
 
I bet you didn't read the paper I posted ? It would be impossible to say that of it ? It is also do-able on a low budget . It goes back to 1931 for inspiration .

Dvv stated I was one of the few people who advocates stereo sub woofers as a necessity . Without me realizing Gerzon says why . Bass needs stereo . It needs wider spacing . If so everything sounds better . Happens in real life .
I read it now.
it's interesting what it claims, although it says it in an unnecessarily convolved way. the diagram featuring the complete system is especially misleading with the "feedback" thing.
anyone tried it? it would be extremely easy to implement in CoolEdit or something like that. I think I'll try it, although it'd be more conclusive to do in real-time.
but I don't know how that advocates stereo subs. subs are crossed way lower compared to the mentioned 600Hz.


To me perfect reproduction means getting the air molecules in the living room to vibrate at my ear drum in a manner that can't be perceptually differentiated from those at the original performance. It's a hugely difficult and complex task but not logically inconsistent and it's far too early to claim 'game over'.
how do you know how the original performance sounded?


Of course. Why take it on faith the control room system revealed everything, or that the engineer was effectively perfect in tweaking the recording to compensate? Recording monitors and home systems are two different views into the same event. Each will be more or less accurate, proclaiming either as an absolute 'standard' is irrational in my view.
someone mentioned earlier a sound engineer I've never heard of. I've looked him up and found names like Jennifer Lopez or the like on his credentials list. I am trying to imagine the average JL listener caring about sound reproduction but I'm failing.
I could nevertheless imagine the ones mixing/mastering such music using typical studio monitors but as far as really serious engineers go, I know for a fact that the gear used for monitoring is no different from what an audiophile would happily buy for home use.
and if your system happens to sound better compared with what was heard in the studio with some random recording, how does it automatiically sound as good with different records, that were mixed/mastered by different people, with different gear? isn't it pretty arrogant to look at the sound engineers as some guys that just do a job, with no interest whatsoever in how the end product actually sounds like? ever considered that maybe at least some of these people actually care about sound and aim to make records sounding in ways that would qualify for the intended usage type, which is, amazingly maybe, home listening?
 
So, let me get this straight - people prefer tubes BECAUSE they have distortion?

Distortion is what helps them get more out of the source?

Holy Moly!

Nige, we need to design a "THD Enhancer" circuit.
This was done and patented in the 1970s. Here's just one of many articles on the "Aural Exciter:"
How Enhancers Work

I've heard of this being used as part of remastering 78s to add in a higher end frequency range that didn't exist on the original disc.
 
...
and if your system happens to sound better compared with what was heard in the studio with some random recording, how does it automatiically sound as good with different records, that were mixed/mastered by different people, with different gear?
My personal experience, and take on it, is that the hearing system craves to hear sound correlating with what it "knows" it should sound like, that the subtle cues riding along at a lower level compared to the main musical threads should "make sense" acoustically - it compares the 'signature' of the sound with its lifetime archive of acoustic memories. If there is a good match then the brain accepts the overall message as being 'correct', and you have "good sound" -- if the match is poor, then the brain dismisses it as artificial, an obvious fake, and it registers as "hifi sound".

Perversely, at times when listening to "good sound" it doesn't come across as being special at all, because it just sounds "normal"; it doesn't attract attention to itself, saying "look at me, look at me!!". This is when one can raise the volume level, up and up, and you realise you have to shout to be heard - the playback doesn't register as being 'loud!', the impression is rather that there is an intensity, a forcefulness to the sound.
 
Exactly. Plus, they are effectively in series - you can't get out more, even with the most sophisticated replay system, than the recording engineer has put into it.

That's ridiculous. In series would entail a microphone recording the studio monitors. Effectively is a hedge. The recording studio is a side chain control loop with feedback. The content is created by the microphones and no justifiable reason exists to claim the engineer even knows everything they picked up, much less 'put it in'. The only recording engineers who 100% create the content are artists like Eno, Wendy Carlos, etc. I'm not convinced reproduction has a coherent meaning in the latter case. Those creations literally don't exist without audio systems, the latter are in a real sense part of the creation chain.
For simplicity I'm only discussing original sonic events that didn't rely on electronic means for creation. Acoustic instruments, singers, etc.. Accuracy to the original sonic event has no meaning when there is no original sonic event.
 
No. It will replace lost tones with the harmonics of other tones.

Now on that I'll provisionally agree. Nothing makes me run faster from a tweak recommendation than describing it as 'adding life'. My only hesitation is that it's not clear to me the proper level of 2nd harmonic in an amplification device can't result in cancellation downstream, including the speakers.
 
Mr Push Pull .

I met an old man who repaired pipe organ . He had a pipe about 26 Hz on the one he was working on .

His first question to me was could I hear the 26 Hz pipe ? I said as far as I could tell no . He then played a few bass pipes ( pedals ) . Again I heard nothing . This is not to say there were no sounds of air escaping .

Next the hand keyboards were played . How did I find the sound ? Squeaky clean and wrong . He beamed to hear me say it .

Next both together . Wow it lifted the roof off the building and so deep and so sweet . So play something you can't hear with something you can and get..........?

As he played faster the illusion vanished . He asked if it was apparent ? I said yes . That is easy was his reply to my puzzled face . He rebuilt organs and was not a professional musician . His brain could not do the timing adjustments to get it to universally work .

The old boy was a Jesuit . He dryly said . You are hearing Hetroydynes . I said do you mean beats ? " Beat you wouldn't understand he said with a glint in his eye , you are an electrical engineer .

I had heard Xavier the resident organist make this organ work . The old man said it was remarkable he could as this organ is truly broken . The old father was fitting solenoid valves to the organ to make it work properly and cheaply . He was using an 8 bit circuit to do the commutation . The old man had taught himself all he need to know . He played me a simple tape deck playing the organ in 8 bit . I was taken aback how good it was . It was working like a piano roll ! He came to me to look at the digital . What he had done was above my understanding and worked . Only now when thinking piano roll I realize even 8 bit is plenty . Hear Gershwin play Prosody in Blue on piano roll . the subtly is incredible considering . I was told there are 32 levels of touch on a piano and that most master 8 . Perhaps , perhaps not . Even so a piano roll or organ roll is remarkable encoding device .
George Gershwin, 1925 Piano Roll: Rhapsody in Blue - Michael Tilson Thomas, Columbia Jazz Band - YouTube

I think Gerzon is saying bass -mid timing matters . Very open mid band is due to the hetrodyning .
 
that's an interesting story but personally I can't see how it relates to Gerzon's paper. I mean it might be related to that but it's just speculation.
meanwhile I'm trying to figure out a way to test it in real-time in software. there are too many parameters (the equalizing, the gain, the panning) that can be altered individually to test it "offline".
 
Feynman said science starts with speculation moving to proof .

How music works is proof . There was no volume control . It was very loud when the organ was played correctly .

Michael was one of the most published members of the AES .

He was remembered most for standing up during a lecture on Dolby surround sound saying with very simple maths why it could not work . Gradually everyone listened . The guys from Dolby were the first to understand . Doubtless even Dolby works better because of that ? Can't stand it myself . Michael said true surround sound would not be dependent on where you sit or where you face . A simple control like a joystick could put you where you should be . The sound-field microphone he invented allows remix centuries later of an original sound . The mics are used for football crowd sound . How sad .

The Ambisonic Bibliography by Michael Gerzon
 
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That's ridiculous. In series would entail a microphone recording the studio monitors.

I guess I was too terse. I meant in series, in that the recording comes first and then the reproduction. In that sense you can only get out of the recording what has gone into it, you can't get back beyond the recording to somehow find out how the original sounded. The recording engineer made his decision and that's it.

jan
 
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My only hesitation is that it's not clear to me the proper level of 2nd harmonic in an amplification device can't result in cancellation downstream, including the speakers.

It can happen of course. But since the amp distortion varies with level and frequency, both in harmonics amplitude and phase, it's a hit and miss. At one moment you might have (partial) cancellation, and the next moment they reinforce each other.

jan
 
That's ridiculous. In series would entail a microphone recording the studio monitors. Effectively is a hedge. The recording studio is a side chain control loop with feedback. The content is created by the microphones and no justifiable reason exists to claim the engineer even knows everything they picked up, much less 'put it in'. The only recording engineers who 100% create the content are artists like Eno, Wendy Carlos, etc. I'm not convinced reproduction has a coherent meaning in the latter case. Those creations literally don't exist without audio systems, the latter are in a real sense part of the creation chain.
For simplicity I'm only discussing original sonic events that didn't rely on electronic means for creation. Acoustic instruments, singers, etc.. Accuracy to the original sonic event has no meaning when there is no original sonic event.
is it only me who finds this argument entirely academic and detached from real life?
here's a video of Bob Katz, taken during a mastering session with the artist himself:
Bob Katz Mastering Session - Juan Carlos Salazar - YouTube

they are actually listening to the result on what could be a typical home-studio chain, containing Pass Labs amps and Lipinsky speakers. as far as my understanding goes, they are trying to create a result that would please them if they were in their homes, listening to a CD they bought.
(and they're ysing stereo subs, btw)
sure, maybe some audiophile owns speakers that are better at bass reproduction, compared to the Lipinsky/sub (unknown brand) combo in the video. and maybe they find that there's something wrong with the bass, and they adjust for it somehow. and then they play some record that was mastered by Bob Ludwig, who uses huge Eggleston speakers. what does said audiophile do?
BobLudwigGateway.jpg
 
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is it only me who finds this argument entirely academic and detached from real life?

Most of the world's population is on your side.

An interesting question for me is how and why the terms of this debate haven't changed since the dawn of recorded music. In defence of academia, an anthropologist, a logician, and a moral philosopher would be useful to have on board.

...they are actually listening to the result on what could be a typical home-studio chain, containing Pass Labs amps and Lipinsky speakers. as far as my understanding goes, they are trying to create a result that would please them if they were in their homes, listening to a CD they bought...

Exactly. Thanks for that. One might hope a studio would have several, representative sets of speakers in addition to whatever they use as a reference.
 
How music works is proof . There was no volume control . It was very loud when the organ was played correctly .
The interesting thing with getting playback to hit the 'sweet spot' is that there is a similar subjective experience: the apparent volume changes quite noticeably as the quality level varies - the ear/brain varies its internal gain control to achieve an ideal 'inner' listening level, to suit the perceived 'realness' of what it hears ...
 
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