What would you want to see in a book on electronics for vinyl replay? Douglas Self.

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My publishers inform me that the 2nd edition of Small Signal Audio Design has reached the practicable limits for the size of a book. (It is 750 pages long) Perhaps it is as well not to write a book you can't pick up with one hand.

I therefore propose to split off all the material in SSAD2 on phono amplifiers and vinyl replay generally, add a bunch of new stuff which I have thought up since, and make it into a separate book.

This is some way down the line (next year at earliest) but I would be very glad to hear opinions on what the book should contain, especially stuff not currently in SSAD2.
 
If you want to be complete, you may want to look at the mechanical aspects of vinyl reproduction as they seem to be as critical as the electrical. I'm not sure if you are comfortable or expert enough to cover them or if a guest author for such a chapter in the book could cover that. But without the mechanical it might possibly be incomplete.

I don't know what is already in your small signal book, but there are other small signal analogue sources that folk are interested in - tape being the one that comes to mind.
 
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What I think is missing from publications I have seen is a section on calibration, by which I mean working with the limitations of the transducer to get a flat response (and alluded to in a response to you in another thread). As you pointed out there are variances side to side as well as between units and the blunt tools of a fixed resistance and variable capacitance are a recipe for peaky HF response.

And extending what Jan said, looking at the HF spectra of click, ticks pops and scratches to see what can be done to reduce those in preparation for A/D conversion is another area that has little coverage in current publications.
 
click, ticks pops and scratches to see what can be done to reduce those in preparation for A/D conversion is another area that has little coverage in current publications.

That will be best solved after A/D conversion, in the digital domain, using a Deep Learning algorithm. But that's like removing the burnt taste from a BBQ, why would you want to ?:cool:
 
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A compendium/summary of fundamental electro+mechanical information, perhaps?

If a book on vinyl replay included a handy compendium of fundamental electro+mechanical information, maybe I could retire my shelf-load of papers and articles. Less time rummaging through Van den Hul’s FAQs, Peter Copeland’s excellent “Manual of Analogue Sound Restoration Techniques”, less time hunting for that Shure technical note by Happ, wondering where I’ve put Ladegaard’s B&K application note ... you get my drift.

I would echo Bigun’s request for a systematic treatment of the mechanical (and perhaps electro-mechanical) aspects of replay. My wish-list would run to the fundamental physical principles of and actual measurements of the:

Mechanics of platter drive, including speed accuracy/variation, perhaps by drive type (idler, belt, DC direct drive, AC direct drive)​
Mechanics of the tonearm, including alignment, and resonance​
Mechanics of the stylus and groove, including the interaction of groove and stylus types​
Electro-mechanics of cartridges, including fundamental principles of mono and stereo transducers, and a survey of motor types (moving coil/magnet/iron) and​
Vibration and noise isolation and control (plinth, platter, plattermat, tonearm and cartridge)​

This is all very much in the mechanical domain – maybe Bigun’s suggestion of a guest author has merit?
 
I would say:

(1) how to determine the noise characteristics of op amps and discrete amplifiers & various associated topologies
(2) how to determine when to choose a current amplifier or voltage amplifier
(3) how to model/design a compensation curve (RIAA)
(4) how to determine correct loading of a cartridge
(5) how to evaluate dynamic range of a phono front end
 
I see a lot going on in vinyl replaying in these pages, especially on DSP supported RIAA eq. Some heavy hitters active there.
So I believe such a dedicated book should include these concepts for sure.

Jan

Hello Jan

Me too, though I have no plans to get into the details of the DSP code. I am aware of Scott Wurcer's article in Linear Audio 10.

Seems to me the best way might be to implement the RIAA HF rolloff in analogue, to maintain good HF headroom and cut down ultrasonics that might cause aliasing, convert to digital, and then do the LF-boost in DSP with as much precision as required.
 
If you want to be complete, you may want to look at the mechanical aspects of vinyl reproduction as they seem to be as critical as the electrical. I'm not sure if you are comfortable or expert enough to cover them or if a guest author for such a chapter in the book could cover that.

I claim no special expertise in the mechanical area. So far as I can see at present, sticking purely to the electronic aspects of vinyl is going to give quite a lengthy book.

I don't know what is already in your small signal book, but there are other small signal analogue sources that folk are interested in - tape being the one that comes to mind.
I plan to point out that tape heads are the other transducers (apart from MM carts) that benefit from load-synthesis, or 'electronic cooling' if you prefer. Perhaps we are having a multitrack revival, but tape seems a bit off-topic to me.
 
What I think is missing from publications I have seen is a section on calibration, by which I mean working with the limitations of the transducer to get a flat response (and alluded to in a response to you in another thread). As you pointed out there are variances side to side as well as between units and the blunt tools of a fixed resistance and variable capacitance are a recipe for peaky HF response.
Hmmm. But how to do it? The data acquisition could no doubt be done by a PC, but you would need to buy an expensive test record. I will ponder this, but I'm not sure I can add much to what Burkhard Vogel has done.

And extending what Jan said, looking at the HF spectra of click, ticks pops and scratches to see what can be done to reduce those in preparation for A/D conversion is another area that has little coverage in current publications.
Now I have plans for that. I have been looking hard at ultrasonic filtering with the avoidance of A-D aliasing in mind.
 
If a book on vinyl replay included a handy compendium of fundamental electro+mechanical information, maybe I could retire my shelf-load of papers and articles. Less time rummaging through Van den Hul’s FAQs, Peter Copeland’s excellent “Manual of Analogue Sound Restoration Techniques”, less time hunting for that Shure technical note by Happ, wondering where I’ve put Ladegaard’s B&K application note ... you get my drift.

I would echo Bigun’s request for a systematic treatment of the mechanical (and perhaps electro-mechanical) aspects of replay.

I think the mechanical stuff needs a separate book. And I don't think I am the man to write it. Maybe someone else would like to have a go?

My thanks for the responses so far.
 
What would I consider as an USP would be a discussion of engineering and calculating an input stage for a phono amp. I mean, which electronic company today would say 'let's invent an active device for the folks who construct phono stages'. Rather, w e see those devices discontinued (those famous japanese FET's for instance).

So, what we do today is 'hacking' modern devices for ancient purposses, be it singles Q's or integrated circuits.

I'm not sure if I made myself clear, anyway...

Rüdiger
 
Mr. Self:

I enjoyed the first edition of your book.

Digital capture of vinyl output is very poorly documented in my experience. There are a number of phono preamps that output digitized signals. As the last of the cassette tape makers vanishes, the ability to easily preserve (and sometimes in the process, manipulate) records on tape is disappearing also. The software I have used (Audacity, mostly) is very cumbersome.

I realize this may be considered ancillary to electronic reproduction of recorded grooves, but a discussion of digitized vinyl versus CDs, MP3s and cassettes with noise reduction would be most enlightening.
 
I agree on some historical perspective, including the various RIAA circuits that have been used in the past and typical performance. You already have some of that in the current book, but an expansion would be nice. Maybe cover some popular preamp and receiver models over time.

Also agree on calibration and measurement. IMO accurately measuring RIAA response isn't a trivial matter and no matter how much I read about noise, accurate practical measurements seem to be elusive and suffer from limitations of filters, meters and other equipment that I can afford.
 
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