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Amplifier Op-amp Rolling Part 2 [Video]

Op amp rolling is an art, something which cannot be measured and is subjective. Sound is in the " head"; I mean ear of the beholder.
Thanks for confirming that is all just suggestion and placebo.
 
https://www.audiosciencereview.com/...p-amp-rolling-part-2-video.62412/post-2289504

2nd HD is higher than 3rd HD, 3rd HD is higher than 4th HD .....

This is the common distortion signature for single end triodes and jFets. Stair step distortion.
I hope you realize 'flat top clipping' as you refer to it has similar reduction in amplitude if higher order HD. In fact, often much more regular reduction in higher order HD than the example you linked:
1746041337762.png
:

Many devices show the same that are not triode or jfet, like this preamp.
1746042267979.png


Also hope you realize the biggest difference between these is the magnitude of the distortion, it's 30dB worse in your example. I circled the to the sixth HD, please see that they are following the same ratio as your example. This 'voicing' of the HD components as you call it is so common in electronics, not unique to tubes or triodes or jfets, and happens also when electronics are driven to 'flat top clipping'.

Lastly, the other big difference is the noise. It does burry the higher order HD in your data. And with efficient speakers, might be the one thing that is audible in your example.

Edit: typo
 
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Their claim of "voicing" is always related to component choices, or some circuit design for which, they have not verified a thing as far as voicing. This phrase has become a marketing claim to win over people who don't know anything about electronics.
In music production—whether it's mixing or mastering—voicing is done by adjusting the distortion characteristics across different frequency bands. It's not a matter of right or wrong; it's simply a matter of taste. So it's unreasonable to deny that designers of consumer audio equipment also actively engage in voicing in a similar way. Rather than assuming that a designer without any measuring equipment just happened to create something with that kind of voicing by chance, it makes more sense to think that they intentionally added the distortion characteristics they felt were best, based on their own sensibilities. If we're talking about cheap, cost-focused gear, then that's a completely different story.
 
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In music production—whether it's mixing or mastering—voicing is done by adjusting the distortion characteristics across different frequency bands.
When that is done it is not just distortion but above all tonality and certain effects and if that is distortion it is higher than that of audio equipment and it not over an entire mix but for each individual 'instrument' or 'voice'.
So no ... 'voicing' of electronics is nothing like sound manipulation in studios.

I also have never seen anyone in a studio swap op-amps in a console to make the bass tighter, get more 'analog' voices or more 'air' or better 'soundstage' and use a selection of op-amps as an 'effect box'. :D
 
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So it's unreasonable to deny that designers of consumer audio equipment also actively engage in voicing in a similar way.
Again, zero examples where this was verified. Zero. The fashion audio designers I've met didn't have even close to the design chops needed to manipulate distortion by frequency band, so I'm triply skeptical.
 
When that is done it is not just distortion but above all tonality and certain effects and if that is distortion it is higher than that of audio equipment and it not over an entire mix but for each individual 'instrument' or 'voice'.
So no ... 'voicing' of electronics is nothing like sound manipulation in studios.
You probably just don’t know this, but mastering is the process of voicing music that’s already been mixed down into stereo. And even during the mixing stage, a lot of processors are already inserted on the mix bus to shape the overall voicing. There’s a wide variety of gear used for that—from digital plugins that apply distortion with precision, to tube equipment with transformers—and how each piece is used comes entirely down to the engineer’s sense and aesthetic.

So if an end user feels dissatisfied with the typical sound of commercially released music and decides to add their own preferred kind of distortion as a form of voicing, it’s not exactly unreasonable. Sure, one might question applying the same distortion across all material, but if there’s an audio gear designer who constantly feels that the low end lacks distortion, and if there are users who resonate with that, then for you to criticize that as if the material delivered by the mastering engineer is the one and only correct version, and any other preference is unacceptable—that just comes across as snobbish and arrogant, I think.
 
You probably just don’t know this
I suspect he knows considerably more than "this."

Still zero verified examples of home audio electronics that have been "voiced." Zero.
 
Now that we are finished and we all got the t-shirt; can we move on to DAC rolling voicing?
Douk Audio Q11 would be a good test-bed. :eek:
(The output volume-level mismatch between the ESS and AKM can easily be corrected externally.)
Dare I say that the Douk Q11 can even allow op-amp swapping?:facepalm:
Oy!
 
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You probably just don’t know this, but mastering is the process of voicing music that’s already been mixed down into stereo.
No. That is called, well, mastering! It is any and all modification of the music to fit whatever subjective sense the mastering engineer has. It has nothing to do whatsoever with voicing as we are talking about.
 
but if there’s an audio gear designer who constantly feels that the low end lacks distortion, and if there are users who resonate with that,
This is utter nonsense. You can't 'design' an amplifier that has a certain amount of distortion in the low end and is clean in the higher frequencies.
Besides ... when you 'add' distortion it isn't just 'harmonic distortion' you also add IM distortion.
for you to criticize that as if the material delivered by the mastering engineer is the one and only correct version, and any other preference is unacceptable—that just comes across as snobbish and arrogant, I think.
I listen to a lot of music and most popular music that comes out of studios in the last decades is squashed to death with limiters, compressors and is not tonally correct.
Of course there still are well made recordings (fortunately)l.
Any idea what the distortion levels is in such recordings ? Can this be 'rescued' by adding another 0.01 % of distortion in such a way that this improves the sound quality ?

But really ... we are talking about 'op-amp' rolling as a 'tool' to 'voice' electronic equipment here. Not about tube gear intended for musicians, plug-ins intended for recording.
This thread is about using different op-amps that would 'change the sound in an audibly pleasant way' where other op-amps would somehow not be able.

We are talking about differences in 0.001% range for suitable and in audio used op-amps. Not 'a designer adds more distortion in the bass and customers agree'.
We are talking about added distortion products that are 80dB (0.01%) to 100dB (0.001%) below that of the applied signal.
Have a look at the distortion measured by pma and then tell me if that's what is being used in studios to 'voice' the final mix or what 'audio gear designers' use to 'voice' their amplifiers.

Listen to music quite loud, then you attenuate your signal by 80dB what do you hear ? absolutely nothing... that's what you hear.
And now you tell me that when music is being blasted quite loud you can hear that 'silence' and call that 'voicing' ?

I agree about certain tube gear with intentional distortion levels (in the percent range) and undesirable high and frequency dependent output resistance that interacts with the impedance of a speaker. You could call that deliberate 'voicing' and there are people that prefer that 'sauce' pored over everything.
But op-amps that only will differ slightly in distortion in inaudible amounts above 1kHz, is not 'voicing' at all but a marketing strategy and makes use of how the human brain 'works'.
It has ZERO to do with 'voicing' and is literally thousands of times smaller in magnitude than even the most subtle 'plug-in' found in studios.

I know... pretty arrogant of me to state all this.. you must think.
 
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undesirable high and frequency dependent output resistance that interacts with the impedance of a speaker
Except that even this is not really "voicing" as it will cause a different EQ effect with every speaker, so that the box of gain will not have a specific "voice."
 
This is utter nonsense. You can't 'design' an amplifier that has a certain amount of distortion in the low end and is clean in the higher frequencies.
Besides ... when you 'add' distortion it isn't just 'harmonic distortion' you also add IM distortion.

I listen to a lot of music and most popular music that comes out of studios in the last decades is squashed to death with limiters, compressors and is not tonally correct.
Of course there still are well made recordings (fortunately) that have been recorded really well.
Any idea what the distortion levels is in such recordings ? Can this be 'rescued' by adding another 0.01 % of distortion in such a way that this improves the sound quality ?

But really ... we are talking about 'op-amp' rolling as a 'tool' to 'voice' electronic equipment here. Not about tube gear intended for musicians, plug-ins intended for recording.
This thread is about using different op-amps that would 'change the sound in an audibly pleasant way' where other op-amps would somehow not be able.

We are talking about differences in 0.001% range for suitable and in audio used op-amps. Not 'a designer adds more distortion in the bass and customers agree'.
We are talking about added distortion products that are 80dB (0.01%) to 100dB (0.001%) below that of the applied signal.
Have a look at the distortion measured by pma and then tell me if that's what is being used in studios to 'voice' the final mix or what 'audio gear designers' use to 'voice' their amplifiers.

Listen to music quite loud, then you attenuate your signal by 80dB what do you hear ? absolutely nothing... that's what you hear.
And now you tell me that when music is being blasted quite loud you can hear that 'silence' and call that 'voicing' ?

I agree about certain tube gear with intentional distortion levels (in the percent range) and undesirable high and frequency dependent output resistance that interacts with the impedance of a speaker. You could call that deliberate 'voicing' and there are people that prefer that 'sauce' pored over everything.
But op-amps that only will differ slightly in distortion in inaudible amounts above 1kHz, is not 'voicing' at all but a marketing strategy and makes use of how the human brain 'works'.
It has ZERO to do with 'voicing' and is literally thousands of times smaller in magnitude than even the most subtle 'plug-in' found in studios.

I know... pretty arrogant of me to state all this.. you must think.
Sure, if we're limiting the discussion strictly to opamps used as mere buffers or amplifiers like you said, then you're right. But I'm commenting on amirm's post, and I'm talking about the broader picture of 'voicing', including transformers and tube amps.

You're narrowing the discussion to opamps, but when you add a transformer, it's clear that low-frequency distortion increases. Even though there are plenty of ways to avoid that, many mastering-grade devices are still designed that way. On top of that, there are also many professional devices built with opamp-based circuits that are intentionally designed to add such distortion. So what I'm trying to say is that making specially voiced equipment like that for end users and marketing it as something that "makes your sound better" isn't some kind of voodoo.

I personally don't feel the need to use that kind of gear, but just because someone else wants to doesn't mean they should be ridiculed for it. That's my point.
 
That's the topic of the thread... ;)


JSmith
Okay, then let me ask you this—let's take an amplification circuit that uses only op-amps, like a microphone preamp, for example. Can you explain why the Millennia Media HV-3, which is used in an enormous number of professional recordings including jazz and classical, sounds dramatically different from a cheap op-amp-based mic preamp? Not just cheap ones—over the past 30 years, many designers have released preamps, even quite expensive ones, claiming they're better than the HV-3. But the HV-3's dominance in the market still hasn't changed. In the end, isn’t that difference in sound ultimately due to the choice of components and circuit design?
 
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jazz and classical
Do they roll the opamps for each genre?
sounds dramatically different
Hmm...
Noise: 60 dB Gain, 10 Hz – 30 kHz, Inputs common: -133 dB EIN
Total Harmonic Distortion + Noise: 35 dB Gain, 10 Hz – 20 kHz bandwidth, +27 dBu Out: < .001%, Typ. < .0005% (< 5 ppm)
Intermodulation Distortion: (50 Hz & 7 kHz) 35 dB Gain, +27 dBu Out: < .0009%
Noise (60 dBu Gain, 10 Hz - 30 kHz, Inputs common) -133 dB EIN
Total Harmonic Distortion + Noise (35 dB Gain, 10 Hz - 20 kHz bandwidth, +27 dBu Out) < .001%, Typ. < .0005% (< 5 ppm)
Intermodulation Distortion (50 Hz & 7 kHz) 35 dB Gain, +27 dBu Out < .0009%
Noise (60 dBu Gain, 10 Hz - 30 kHz, Inputs common) -133 dB EIN
Total Harmonic Distortion + Noise ( 35 dB Gain, 10 Hz - 20 kHz bandwidth, +27 dBu Out) < .001%, Typ. < .0005% (< 5 ppm)
Intermodulation Distortion (50 Hz & 7 kHz), 35 dB Gain, +27 dBu Out) < .0009%


JSmith
 
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Can you explain why the Millennia Media HV-3, which is used in an enormous number of professional recordings including jazz and classical, sounds dramatically different from a cheap op-amp-based mic preamp?
Are you sure it is due to the used op-amps or could that be caused by the circuit the op-amps are used in and determines the loading of the mic/instrument input for instance.
And of course op-amp choices, particularly in mic/vinyl cartridge situations where high gain and low noise is essential it matters which op-amps are used and above all which components and circuit (and even layout).
No one denies that. I would not call that 'voicing' but rather proper design procedure.

And of course transformers and low feedback FET or tube amp designs can 'color' the sound. One could call that 'voicing' if one wants to but in the end it is just a changed transfer function or bandwidth limiting.
Voicing (to me) is better used when speaking about transducers.

Is there a plug-in for studio usage that lets you select a wide range of op-amps (in unity gain or just a few dB gain) and all having an FR responses flat from DC to 50kHz ?
Specifically to 'voice' a recording ?

Nah .... you can't 'voice' amplifiers with different op-amps. One can select op-amps to make a circuit work optimally though ... but that is not 'voicing'.
 
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Can you explain why the Millennia Media HV-3, which is used in an enormous number of professional recordings including jazz and classical, sounds dramatically different from a cheap op-amp-based mic preamp?
Which "cheap op-amp based mic preamp" specifically? And where was this verified?

And to Amir's point, this has zero to do with music reproduction, any more so than studio plug-ins.
 
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