Small Signal Audio Design 3rd edition: Douglas Self

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I have no issue in describing sound subjectively and you can see from some of the project write-ups on my DIY site - I almost always do a subjective write-up once the thing is boxed up and I’ve ironed out any bugs.

The issue is more to do with folks claiming you have to do x or y to ensure good sound. One of the worst I read about 18 months ago in a UK web HiFi magazine was the one about SMD components ‘constrain’ the sound, and the reviewer then went on to conclude that anything using SMD devices should be treated as suspect. You hear the same stuff with amplifier topologies, tube vs solid state, JFET vs bipolar etc.

And, the worst cliche of course are the ‘my jaw dropped on the floor the sound was that good’ or ‘the amp was so good I could walk around a 3D holographic sound stage’.

And let’s not even get started on cables and ‘grounding boxes’ where I’ve had to endure some wag at a show attaching one to an unused input on a preamp (one of mine), step back and say breathlessly ‘my god! You hear how that’s opened up the sound stage’

;)
 
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I have actually experienced a mildly attenuated form of what Jan references both with an ex-wife, and at two friend's homes..

Around here I am much more likely to hear something along the lines of: "OMG what have you done, it's much louder now than it used to be! Or the bass is shaking the living room floor worse than before..."[AKA as an unsubtle hint to turn it down!]

In one instance it was going from a single amp per channel to tri-amplification, and in the other a new program in the DSP processor..

I did get a backhanded compliment once when my wife told me she had told a friend that their stereo sounded like crap compared to her husband's.. LOL I'm not sure they're still friends.. hehe.

I regard the magazines as nothing more than entertainment, and am much less offended by so doing, that said I can't read the stuff anymore, and don't want to hear audiophile hyperbole in person anymore either. [Have I become a crotchety old geezer? LOL]
 

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"Sound so good it fooled my dog."

I used to record live concerts. Sometimes I brought my dog. Dog paid NO attention to anything on the monitor speakers.

I think dogs know speakers are "fake", the same way they know the dog in the mirror can't be smelled and therefore is not real. (Yes, I've heard of dogs who don't get that; and we've had bluejays go nuts over the bird in the window.)

Except once. A dance with a long quiet passage. Dancer wore a long string of beads. The string broke, beads bounced all over the stage. My dog lifted his head at that sound from the monitors! (Probably sounded like kibble on a wood floor.)

I take that back. The nature TV show sometimes has wolf pups crying. This excites our Corgi, more than momentarily.
 
I did get a backhanded compliment once when my wife told me she had told a friend that their stereo sounded like crap compared to her husband's.. LOL I'm not sure they're still friends.. hehe.

To quote my wife, “The problem with your (music) system is that it makes everything else I hear sounds bad!”

I suppose there’s a complement in there somewhere...........
 
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I have actually experienced a mildly attenuated form of what Jan references both with an ex-wife, and at two friend's homes..

Have you read SY's article in Linear Audio Voil 2 'Testing, 1, 2, 3 ..'? He could illicit the effect at will. It was enough for him to play a specific piece of music which he always plays after doing mods ... :cool:

Jan
 
The issue is more to do with folks claiming you have to do x or y to ensure good sound. One of the worst I read about 18 months ago in a UK web HiFi magazine was the one about SMD components ‘constrain’ the sound, and the reviewer then went on to conclude that anything using SMD devices should be treated as suspect. You hear the same stuff with amplifier topologies, tube vs solid state, JFET vs bipolar etc.

Well, that's a new one. I am surprised that he put that forward as avoiding SMD is going to be near-impossible unless you confine yourself to vintage gear.

All the new opamps etc are SMD only, which makes things hard unless you invest in a lot of gear.
 
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News to me too, I embraced SMD quite a while ago and my gear is a mix full of SMD, tubes and mosfets. I will admit to having been called a heretic on more than one occasion. LOL

One could argue that the lack of leads is a benefit.. lol I particularly like those thin film Panasonic precision resistors. I stick to 1206 where possible, these shaky hands and bad eyes don't like anything smaller than 0805.
 
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Well, that's a new one. I am surprised that he put that forward as avoiding SMD is going to be near-impossible unless you confine yourself to vintage gear.

All the new opamps etc are SMD only, which makes things hard unless you invest in a lot of gear.

Doug, the anti SMD thing has been doing the rounds for about 2 or 3 years. I’ve not heard it in any of the mainstream printed magazines though. I’ll try and dig up the review

I’m a pretty dab hand at putting down SMD manually - TSSOP 28 and 64 pin devices ( micro controllers) at 0.5 mm pin pitch no problem!
 
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News to me too, I embraced SMD quite a while ago and my gear is a mix full of SMD, tubes and mosfets. I will admit to having been called a heretic on more than one occasion. LOL

One could argue that the lack of leads is a benefit.. lol I particularly like those thin film Panasonic precision resistors. I stick to 1206 where possible, these shaky hands and bad eyes don't like anything smaller than 0805.

I actually prefer placing SMD - I’m most comfortable at 0805, SOT23 and SOD323 and bigger.
 
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Here’s the review. There are others but I’d really have to root around some more.
 

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Here’s the review. There are others but I’d really have to root around some more.

Whoever wrote that review knows very little about electronics. eg

...I found the amplifier to be absolutely stable without even a hint of getting warm...

...military specification wiring to eliminate interference from power supplies...

...proprietary IEC socket...
 
If you're going to talk SMD components, you might as well include solder, as that has been "proven" in the past to effect how it sounds. Solder types making an audible difference when used to construct devices with a large number of connections, such as an entire receiver.

I like the "my subjective impressions of sound systems and other machines depends at least as much on my own state of health" idea and of course find this to be personally true. Elsewhere in DiyAudio it was noted that the brain can easily and automatically correct for physical reality phenomena, such as combing resulting from two stacked drivers - or other aspects of "measures sh*tty, sounds great". I wonder what else the brain can do, given there's "desire" for it to sound good. Such a discussion might detract from the essence of your book however.

I have a vintage stereo 6BQ5 amplifier who's build steps all over huge no-no's in electronic audio design (such as steel chassis in the feedback signal path, ceramic discs in the signal path, screen B+ shared with signal tubes) yet it still sounds pretty good. Is it my point source FR speakers, my input source or my brain - or is the combination of it all somehow "really OK"; i.e. another casually listening would agree? Maybe a chapter on how this is possible in the context of both small signal electronics and human perception would be an interesting read!

You may want to include a chapter on "Software Defined Amplifiers" - the audio analogy to software defined radios. I believe this is coming, if not already here - where you can tune an amplifier's response in software to accommodate, say, driving just a tweeter. Or adjust its harmonic spectrum content from a software control. Or change the output damping factor likewise. You could still lean heavily toward the electrical "small signal" aspect of connecting multi output DSP sound cards into, say, tube circuitry that would enable control of such features - leave the software part as an exercise for the reader ;')
 
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I have a vintage stereo 6BQ5 amplifier who's build steps all over huge no-no's in electronic audio design (such as steel chassis in the feedback signal path, ceramic discs in the signal path, screen B+ shared with signal tubes) yet it still sounds pretty good.

It has the steel chassis in the feedback path? What??

Ceramics in the signal path is a definite no-no unless you want extra unpredictable distortion.

I have absolutely no opinion on screen grid voltages in tubes.

You may want to include a chapter on "Software Defined Amplifiers" - the audio analogy to software defined radios. I believe this is coming, if not already here - where you can tune an amplifier's response in software to accommodate, say, driving just a tweeter. Or adjust its harmonic spectrum content from a software control. Or change the output damping factor likewise. You could still lean heavily toward the electrical "small signal" aspect of connecting multi output DSP sound cards into, say, tube circuitry that would enable control of such features - leave the software part as an exercise for the reader ;')

I think here you're talking about power amplifiers, and digital ones at that. That is rather outside the scope of a book on small-signal design.
 
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