Douglas Self- New Small Signal Stage Book Imminent!

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Mark Burnley

Well-known member
Joined
Jun 3, 2004
Messages
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Location
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Hi,

Massive fan of Douglas Self Power Amp books, and Self On Audio is bedside reading...

His new book is out late January, and looks like it'll be worth picking up-

Small Signal Audio Design

Here's what he calls "supplementary material" for the new book.

He tends to leave No Stone Unturned, which usually gives a good read, and hard facts too.

Plus, he has a sense of humour, which is no bad thing in the rarefied air of professional electronics/audio authorship!

He's definitely up there with Pease/Jung/Williams et al.

Mark
 
My copy has just arrived from Amazon.  I've only had a chance for a quick browse, but it looks really good, and I've picked up a few interesting ideas already.  There are lots of example circuits, e.g. starting with something fairly basic and developing it through several levels of increasing refinement.  You could use it like a cookbook, but there seems to be enough detailed explanation for some proper learning too.  The style reminds me a little of Horowitz and Hill - very readable and a good blend of theory and practical experience.

Steve.


 
Great!

Mine should be here soon...

It looked good from the chapter titles/preview.

Looking forward to a good read...

...and the later discussions here, of course.

:)

Mark

 
I too am a fan of Douglas Self. His new book arrived today from Amazon
It's excellent - I've been reading it for the last couple of hours. There is more
humour too. Wide range of topics, plenty of new stuff. Worth the money in my
opinion.
 
I got mine today. Great Book !

I like his scientific approach to talk about how components could change the sound with a lot of AP measurements graphs, rather than subjective points of view. I found his approach similar to Ethan's in some way... Although he has a sense of humour, I definately see him as a serious guy :)
 
Yeah, just received my copy the other day and been reading it ever since. Really like the humour injected here and there, plus the sort of off-topic info that comes accross different topics every now and then. Really teaches a lot :)
 
Got mine on Friday (ordered in January!) and I'm about half way through.  Lots of good stuff and I love the 'accept no bullshit' style. I watched an AES lecture of his, so I can hear his voice as I read the book.  He's a funny guy  ;D
 
there is an ebook version available, but not compatible with kindle etc... it's in a .VBK standard.

really? the whole world has gone PDF + Kindle... and these aholes decide on a proprietary standard?

(Mr Self is not a part of the publisher... and therefor, most definately not an ahole...  ;) )
 
It is an excellent book, and I recommend to get a copy. Nonetheless there are several things which need correction or at least some extension--in particular I find the chapter on opamps rather disappointing (his explanations on the internals of the NE5532 are basically just plain wrong). I'd hesitate with comparisons to the heavyweights of IC technology.

Samuel
 
Samuel,

I have just got a copy and got to that part. Could you point out the bits on 5532 that you think wrong? I have heavy-weight books in my library but I also value your views.

However, it is indeed a really good book for fast, straight to the point explanations without getting involved in the heavy theory and math.
 
I don't have the copy at hand right now so just the basic things from memory: one of the caps is actually a feed-forward cap, not a feed-back cap as he thinks. That way there isn't actually that much nested feedback in the NE5532, and the remaining bit is just a necessity for stability rather than an ingenious engineering result. The low distortion is very unlikely attributed to the four-stage architecture per se but mainly to the relatively high quiescent current in the output stage. The four-stage architecture is more of a necessity to get around slow lateral PNPs rather than a convenient thing for low distortion; the topology is difficult to compensate and results in a rather slow amplifier compared to other topologies (either using complementary processes or more recent four-stage topologies) at similar quiescent current. Unlike he notes there is a substantial amount of material available on this topology (though not on the NE5532 per se); there are numerous amplifiers which use it. LT1007, OP07, OPA177 and LT1115 just came to my mind within 10 seconds.

Another striking error is that he claims that the AD797 uses no input bias cancellation. No current bipolar IC amplifier could simultaneously achive that low voltage noise and low input bias current without some sort of cancellation. That the datasheet does not mention it is hardly much of an argument, and in fact the AES preprint by Scott Wurcer does mention the bias cancellation. After that I'm not at all that sure if the LT1115 has higher current noise as he claims--at least we'd need to verify it (I'm about to do it once I've got a free hour).

Samuel
 
I'm inclined to take Sam's word for it wrt the IC comments. I would qualify one comment made, the 553x was not "slow" for it's peer group back in the '70s, or slow for general audio waveform needs. It suffers in comparison to modern process and technology advancements but what else is new for 30+ year old technology.

This doesn't mean the Self book is not a good read, we all can make a bad call from time to time (or at least I do).  It's never a good idea to be overly invested in one expert and just take his word for stuff. Strive to learn and understand how stuff works and be your own expert. If his book helps take you to higher level of understanding it's worth every penny. 

I miss the good old days when the IC makers published schematics of their inner circuitry. Sometimes hard to grok since they can fabricate exotic devices (like multiple collector or whatever transistors) inside ICs useful for sundry applications. The inner workings are academic for cookie cutter design work, but useful when pushing the envelope.

JR
 
Unfortunately (may be fortunately) a great deal of my professional life required me to be jack of all trades and  I did not have the opportunity to get involved in audio design at the level of the masters here. Therefore I find books, periodicals, papers, schematics etc. as an oportunity to learn from others' experience. This book is not meant to be a definitive book on the subject. But it is certainly worth every penny from a point of offering some of his years of experience. But as you said there can be bad calls at times. I'll investigate the points Sam raised.
 
C1 is the feed-forward cap which passes the signal around the lateral PNPs Q3/Q4 at high frequencies--note that all other transistors in the direct forward path are NPNs.

Again I do very much respect his work--there's simply no comparable book around at the time of writing.

Samuel
 
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