Bob Cordell's Power amplifier book

Hi Chris,
Yes, I understand that is how you explain to yourself why we disagree. Similarly, I have my own way of understanding your views. Its based on my belief that you have strong overconfidence bias, and you have a strong sense of Naive Realism:

In social psychology, naïve realism is the human tendency to believe that we see the world around us objectively, and that people who disagree with us must be uninformed, irrational, or biased.
https://en.wikipedia.org/wiki/Naïve_realism_(psychology)

Of course we are both human and have our own explanations for each other. Its only natural for it to be so. I only hope it is okay for me to speak honestly about it.
 
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Mark, I am talking about the reality of the situation. The physics and actual way things work. I don't have to explain anything to myself at all, my belief system is based on what actually happens.

This has zero to do with being human or what goes on in our heads. Not unless you are talking about expectation bias, and that is what you are subject to. Not me, I am getting actual, measured evidence. Something many people hate because it is fact and right out there in front of you, verifiable by anyone with similar equipment 100% of the time in any lab or even just a work bench in this case.

Nope, I'm not special nor are people who do the same thing. No ego boost here, just relating facts to some folks who do not want to hear about it. It drains the fantasy out of the situation.
 
Purists hate compression, but musicians love it. Aside from, maybe, classical music, all modern music (ab)uses compression. There are several architectures, FET, VCA, opto, etc... But it seems that most of the modern app notes focus on VCA applications, probably because they want to sell you a VCA and not a FET, and opto cells are many times custom-made, aside from the opto cell of an LA2A or something similar, which you may find on the internet.

I do not necessarily agree with your statement implying that good recording engineers do not abuse compression, although, one could make an argument for what a good audio engineer is in the first place. I can tell you that an audio engineer who refuses to use too much compression in modern music is, most likely, an unemployed engineer. Chris Lord-Alge (and his brother Thom) are notorious for their excessive use of compression, they probably are (definitely were at some point) the most coveted audio mixers of the music industry, mixing thousands of records, winning several Grammys and earning the big bucks. I can guarantee that if you've listened anything from the 2000s till now, you have listened more than once to something these guys made. These are two examples but they are not the only exception. On top of that, mastering engineers completely destroy the sound by excessive compression and limiting, leading to what has been known as the 'Loudness Wars', although since Spotify and other streaming services started normalizing all the audio to -14 LUFS or thereabouts (the user can deactivate normalization but it is on by default, and the majority of regular users won't even know or care about it) this has lead to less compression abuse by mastering engineers, but the problem of excessive compression/limiting still remains. However, 99% of modern music is heavily compressed or has used heavy compression as an effect at some point of the production process.

I don't want to turn this into an argument about whether excessive compression is good or bad, rather, the point I am trying to make is that it is essential. Also, I don't care about the discussion about whether audio compression itself is good or bad, because compression use or abuse is a subjective issue, and I don't care too much about subjective issues. My goal is circuits.
The VCA-based compressors are preferred by many designers because their control characteristic is very predictable. Of course, this does not necessarily make them sonically or subjectively better. Proper compression with FETs and opto usually requires matching of devices or trimming. Matched voltage-controlled resistor (VCR) JFETs are available in dual monolithic form from Linear Systems, for example. However, the threshold and IDSS of the pair can vary over a significant range (as with most JFETs).

Among the most revered compressors among numerous professionals are the vacuum-tube compressors made by Fairchild long ago. Many are still in use, but the remote-cutoff tubes in them used for the gain control element are difficult to come by. The modern tube compressors made by Manley are also popular in the recording studio.

The loudness wars have killed a lot of music for audiophile listening, and I hate it. Such compression used across the full frequency range on all instrumets is bad. I'm mostly talking about compression used wisely and surgically in the recording studio. I agree, however, even there it can be over-used, and sometimes used for effects (like deliberate breathing of midband content by bass content). Of course, regarding effects, I hate Autotune.

One of my favorite tracks for dynamic range is "Getto of my Mind" from the Flying Cowboys album by Rickie Lee Jones. The original releqase has very little compression and the thwack of the snare drum is very impressive. This is in the original release. There was so much high-amplitude dynamic range that it was recorded at an unusually low average level, so one had to up the volume control to get the same overall perceived loudness. There was a subsequent release that employed more compression, unfortunately.

Cheers,
Bob
 
...ad hominem attacks.
You don't seem to understand there was no attack at all, unless it maybe it was Chris trying to imply I don't know what I am doing, but he does. Why isn't that an veiled attack?
What I said certainly wasn't an attack. It was a statement of truth about what goes on inside my head. It explains why it is useless for Chris and I to argue with each other rather than just live and let live.
 
The VCA-based compressors are preferred by many designers because their control characteristic is very predictable. Of course, this does not necessarily make them sonically or subjectively better. Proper compression with FETs and opto usually requires matching of devices or trimming. Matched voltage-controlled resistor (VCR) JFETs are available in dual monolithic form from Linear Systems, for example. However, the threshold and IDSS of the pair can vary over a significant range (as with most JFETs).

Among the most revered compressors among numerous professionals are the vacuum-tube compressors made by Fairchild long ago. Many are still in use, but the remote-cutoff tubes in them used for the gain control element are difficult to come by. The modern tube compressors made by Manley are also popular in the recording studio.

The loudness wars have killed a lot of music for audiophile listening, and I hate it. Such compression used across the full frequency range on all instrumets is bad. I'm mostly talking about compression used wisely and surgically in the recording studio. I agree, however, even there it can be over-used, and sometimes used for effects (like deliberate breathing of midband content by bass content). Of course, regarding effects, I hate Autotune.

One of my favorite tracks for dynamic range is "Getto of my Mind" from the Flying Cowboys album by Rickie Lee Jones. The original releqase has very little compression and the thwack of the snare drum is very impressive. This is in the original release. There was so much high-amplitude dynamic range that it was recorded at an unusually low average level, so one had to up the volume control to get the same overall perceived loudness. There was a subsequent release that employed more compression, unfortunately.

Cheers,
Bob
Agree with everything you said. Still, I would dare to say that FET compressors are more popular in studio use than VCAs. Musicians/audio enthusiast tend to perceive VCAs as being more aggressive and more suitable for percussive instruments or bus compression (e.g., the SSL buss compressor), whilst they tend to perceive FET compressors as more of a 'good-for-most-things' kind of tool, which includes drums, vocals, guitars and so forth. IC manufacturers absolutely favor VCAs for all the reasons you mentioned, however, in general, musicians and studio engineers tend to think otherwise, and these are the people buying them.
 
You don't seem to understand there was no attack at all, unless it maybe it was Chris trying to imply I don't know what I am doing, but he does. Why isn't that an veiled attack?
What I said certainly wasn't an attack. It was a statement of truth about what goes on inside my head. It explains why it is useless for Chris and I to argue with each other rather than just live and let live.
It was the textbook definition of an ad hominem attack. He expressed his opinion based on the matter and you went about saying how he has a "strong sense of Naive Realism" without even making mention of anything he said in his post. But lets leave it at that, I don't want to start a back-and-forth about what constitutes an ad hominem attack and what not. I will take on your offer of live and let live.
 
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My issue is that by pulling in subjective opinion that isn't based on carefully controlled tests muddies the waters to a point where we may as well all give up and go home. You can't open the door to everything simply by invoking what we may or not hear. Especially without any form of carefully controlled testing by more than one group of actual trained professionals.

There are studies showing what can be heard as jitter or time domain problems. Often subjective opinions claim perception well beyond those limits because someone feels they are special or specially trained. All I have ever said was that we can test, repeatedly, to and beyond the limits of what the human body can sense in any way imaginable (that is fact). So unless you are going to put in the time and effort to do things right, and spend the money to be able to measure beyond human limits, I feel you can have an opinion but it is only yours and science trumps it every time.

Basically, you can't call out your personal opinion as being more factual than proved science. Today we easily measure far beyond what we could before 2000, most subjectivist opinions were formed in the 1970's. So basically, study and get with the program. Unfortunately anyone can find claims to support any belief on the internet simply because there is not peer review or requirement to be factual with anything.

So, grab an oscillator that is stable. Use the tuning methods to introduce measured amounts of jitter with monitored waveforms and measure what people can pick up in a carefully controlled way. I can do that, but haven't the time. If I were being paid to do this - sure, but I work for a living and do get paid for these skills.
 
Agree with everything you said. Still, I would dare to say that FET compressors are more popular in studio use than VCAs. Musicians/audio enthusiast tend to perceive VCAs as being more aggressive and more suitable for percussive instruments or bus compression (e.g., the SSL buss compressor), whilst they tend to perceive FET compressors as more of a 'good-for-most-things' kind of tool, which includes drums, vocals, guitars and so forth. IC manufacturers absolutely favor VCAs for all the reasons you mentioned, however, in general, musicians and studio engineers tend to think otherwise, and these are the people buying them.
I am not a recording engineer, but I think you may be exactly right. A high-quality, precision FET-based compressor will tend to be more expensive than a VCA compressor, due to the inherent variability of JFET characteristics.

There is another possible issue that muddies the water between JFET compressors and VCA compressors. That is the specific behavior and design of the control circuitry that, for example, controls the attack/release times. The specific circuitry for that function will tend to be necessarily different due to the different nature of the control element.

There is a second issue that can muddy the waters. The architecture of the compressors can be different. Some compressors are feedback compressors while others are feedforward compressors. This can obviously make a difference. I believe that most traditional FET-based compressors are of the feedback nature (meaning that the control voltage is derived from the output of the compressor).

Cheers,
Bob
 
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Often subjective opinions claim perception well beyond those limits...
Because the tests were flawed? Because they were looking for audibility of far-out phase noise, not close-in? Because Thresholds of Audibility are estimates of the center of a bell curve? That the bell curve was almost certainly was assumed to be Gaussian, which may not be the right bell curve. Professor Bart Kosko has made that problem quite clear: what are presumed to be rare events (outliers) may not be so rare after all: https://www.edge.org/response-detail/11715

Chris, every point of your argument can be refuted and or challenged one by one. Shall we stop here or keep arguing? Probably best to let you have the last word and leave off there?