Objectivity vs Subjectivity

I realised after about 5 years into the hobby that my emotional response to a system playing music have no correlation with how best it adheres to the mainstream accepted and published measurements. There are some fundamental measurements that I would call " basic engineering ones " that I look up to get to a common sense - baseline. Beyond that, I have found that everything is all over the place and it is only actual audition that determines how my emotional response will be.

Bingo. This is my sentiment as well.

Since I am a science-driven person, I have made an attempt to figure out what specs correlate to sound I like or what contributes to sound I file lacking soul.

I think global feedback is the biggest culprit. Something about high global feedback amps messes with timbral accuracy, IMO.
 
Bingo. This is my sentiment as well.

Since I am a science-driven person, I have made an attempt to figure out what specs correlate to sound I like or what contributes to sound I file lacking soul.

I think global feedback is the biggest culprit. Something about high global feedback amps messes with timbral accuracy, IMO.
Trying to understand the “Global feedback in amp design “ I came across this.
I am now even more mystified.
Is there a layman’s version to explain this?
 
Trying to understand the “Global feedback in amp design “ I came across this.
I am now even more mystified.
Is there a layman’s version to explain this?
Seems to be the same as negative feedback
I think @IndianEars ears had posted not too long ago on how Negative feedback can be used to reduce distortions and are also (mis)used to show very low distortions in specs but at the expense of sound when you hear it.
 
Yes. I meant global negative feedback. High anoints of that make the spec sheet look good and also increase the damping factor - but - IMO - suck the life out of the music.

I wonder if it is second order harmonics that actually provide timbral cues. Single ended tube amps have a lot of this and do much better here - push pull tube amps with negative feedback measure well but also lack that magic. So it isn’t tubes per se.

It would be interesting to make a zero feeeback solid state amp and see how that sounds.
 
Yes. I meant global negative feedback. High anoints of that make the spec sheet look good and also increase the damping factor - but - IMO - suck the life out of the music.

I wonder if it is second order harmonics that actually provide timbral cues. Single ended tube amps have a lot of this and do much better here - push pull tube amps with negative feedback measure well but also lack that magic. So it isn’t tubes per se.

It would be interesting to make a zero feeeback solid state amp and see how that sounds.
A post by Nelson Pass gives some idea.
 
Yes. I meant global negative feedback. High anoints of that make the spec sheet look good and also increase the damping factor - but - IMO - suck the life out of the music.

I wonder if it is second order harmonics that actually provide timbral cues. Single ended tube amps have a lot of this and do much better here - push pull tube amps with negative feedback measure well but also lack that magic. So it isn’t tubes per se.

It would be interesting to make a zero feeeback solid state amp and see how that sounds.

Since this actually reduces distortion I presume the gain of the amplifier will need to be reduced quite a bit and that impacts the drivability of the speaker most of the First watt amps vary between 11-20 dB and claim to be zero feedback .

Even for my relatively sensitive Tannoys I need at least 32-35 db of gain across pre/power to drive them. Even a 26 db amp was having a problem until I put in an active preamp.
 
My SET tubeamp has zero feedback and will at full volume give around 3 watts. I never go above 9oclock volume position and have measured around 300mWatts as sufficient to drive my speakers.
 
I quote from Bruno Putzeys:
"Nobody with a solid working knowledge of feedback theory chooses to avoid it. “I choose to avoid feedback” is an all too transparent code for “I’ve yet to figure it out”. Perhaps the biggest myth surrounding feedback is that it is a quick and easy fix. It isn’t. Feedback is a fascinating and complex topic that lies at the core of successful design."
 
Since this actually reduces distortion I presume the gain of the amplifier will need to be reduced quite a bit and that impacts the drivability of the speaker most of the First watt amps vary between 11-20 dB and claim to be zero feedback .

Even for my relatively sensitive Tannoys I need at least 32-35 db of gain across pre/power to drive them. Even a 26 db amp was having a problem until I put in an active preamp.
Please note that some of the Firstwatt amps may not use global negative feedback but may use local negative feedback.
 
Below is a link to a long article on Single Ended v Push Pull amps.
Scroll down to page 8 and you’ll find a detailed explanation of Negative Feedback.

SE v PP
 
Seems to be the same as negative feedback
I think @IndianEars ears had posted not too long ago on how Negative feedback can be used to reduce distortions and are also (mis)used to show very low distortions in specs but at the expense of sound when you hear it.
My post on Amplifier Feedback & feedforward is here:

 
I quote from Bruno Putzeys:
"Nobody with a solid working knowledge of feedback theory chooses to avoid it. “I choose to avoid feedback” is an all too transparent code for “I’ve yet to figure it out”. Perhaps the biggest myth surrounding feedback is that it is a quick and easy fix. It isn’t. Feedback is a fascinating and complex topic that lies at the core of successful design."

Meh. That quote by itself adds nothing new to the topic. Yes, we know feedback is popular - that is how most people make ”well-engineered” amps: you know, the ones with great measurements and vanishing low distortion.

The above concept is precisely what I am pushing back against -and not just me. There is a reason so many people find flea-powered SETs with zero feedback amazingly musical.

Being a sound engineer or even an amp designer does not give someone a monopoly on deciding what sounds better. It merely means that they have one particular method to achieve their chosen design or recording goals. The goals themselves vary from person to person.

So in short, quoting some guy isnt any kind of definitive rebuttal.
 
My SET tubeamp has zero feedback and will at full volume give around 3 watts. I never go above 9oclock volume position and have measured around 300mWatts as sufficient to drive my speakers.

Same here. 3WPC, i have never turned the volume beyond 9-10 and it is the only system with which i have received complaints from neighbors.
 
Genelec System was mentioned.
John Abraham (Self confessed audiophile) has Genelec system at his place.
regards.
 
Purchase the Audiolab 6000A Integrated Amplifier at a special offer price.
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