Bob Cordell's Power amplifier book

Certainly your VISIO drawn schematics are a thing of beauty in this book, especially when compared to the LTSpice ones (see fig 19.1 for an example). The square wire junction nodes give that a somewhat clunky feel. Overall I really appreciate the visual (rather than mathematical) feel of this book. Its reminiscent of that other great 'bible' in electronics, Horowitz and Hill.

I have a suggestion for adding to your website Bob. I'm guessing the VISIO schematics don't produce LTSpice compatible netlist output, so why not maintain a cache of LTSpice versions of the schematics shown in your book on your website? I don't suggest you spend time inputting the schematics again, but how about inviting readers to upload their own or send them to you by email? This way you'll facilitate experimentation with your circuit examples and potentially have some worthwhile reader contributions to the 2nd edition ;)

Hi Abraxalito,

This is a good idea, and is pretty much in line with what I have planned for the supplemental book material that I'm going to put up on the web site. What I plan to put up is as follows:

- reasonable models of the transistors I used in the numerous simulations referred to in the book. This is not a large collection, but is enough to simulate the ready-to-run simulations I will provide. These models will not be perfect (none are), but they will have been sanity checked by me and at least tweaked somewhat if not done largely from scratch.

- simulations of most of the examples in the tutorial LTspice chapter 19.

- some number of amplifier simulations.

- probably some other simulations that were done for the book, such as some output stage simulations.

What gets put up will of course be a function of time.

Many of the schematics that were drawn with VISIO actually started as LTspice simulations, such as virtually all of those in Chapter 3, so those simulation files already exist and just need to be cleaned up a bit before I put them up.

Cheers,
Bob
 
The evaluation version is limited in the number of components, that is, as far as simulation is concerned. AFAIK, this limitation doesn't apply if used as schematic capture only pgm.

BTW, it seems that VISIO is from micro$hoft. That says enough already. However, the size of the installation file is 293MB. That says more than enough. Bloatware :(

Hi Edmond,

I know what you mean about MS; I curse out my windows operating system at least once or twice a day. However, I must say that I think VISIO is a good program that works well for me. However, I use VISIO 2002 at home. The newer VISIO (I think 2007) I do not like as much as they added more fancy stuff that no-one uses at the expense of ease of use for most operations.

Cheers,
Bob
 
Hi Abraxalito,

This is a good idea, and is pretty much in line with what I have planned for the supplemental book material that I'm going to put up on the web site. What I plan to put up is as follows:

- reasonable models of the transistors I used in the numerous simulations referred to in the book. This is not a large collection, but is enough to simulate the ready-to-run simulations I will provide. These models will not be perfect (none are), but they will have been sanity checked by me and at least tweaked somewhat if not done largely from scratch.

- simulations of most of the examples in the tutorial LTspice chapter 19.

- some number of amplifier simulations.

- probably some other simulations that were done for the book, such as some output stage simulations.

What gets put up will of course be a function of time.

Many of the schematics that were drawn with VISIO actually started as LTspice simulations, such as virtually all of those in Chapter 3, so those simulation files already exist and just need to be cleaned up a bit before I put them up.

Cheers,
Bob

I went through the book but not yet fully in depth. It is what I was looking for.
The only place where I would like to see some addition is in the part related to the front end input stage and Vas
It is always difficult to make a presentation which well balanced between maths à la textbooks and technical descriptions à la Self or Sloan.
I would suggest to add on your site some more technical desciptions of the front ends and Vas with relevant equations; it would be nice to see also descriptions with pro and cons of fully symetrical designs, fully ballanced design, folded cascode ones and better analysis of complementary Vas which is called in the litterature class AB amplifier.

Presentation of poles zeros graphs with respect to current, output impedance with respect to current for these stages would be very usefull.
I would love to see these aspects treated in the same simple way ( back of the envelope calculation) but audio oriented as Sansen in his book " Analog design essentials"

The presentation could be like he is doing, power point slides including circuit schematics and simple design equations for each circuit
Power point slides with more in depth equations of the different topologies would be a tremendous add on to the best book on audio amplifiers.

JPV
 
I got my copy on Wednesday here in Poland.
But I canceled my order at amazon.co.uk and put a new order at amazon.US.

I'm starting to read the book, and I love your writing style.
Good job Bob


I'm really glad you like my writing style and appreciate the kind words. It is one thing for an engineer to be congratulated for his technical substance, but really extra nice to be told that his writing connects with the reader.

Cheers,
Bob
 
I went through the book but not yet fully in depth. It is what I was looking for.
The only place where I would like to see some addition is in the part related to the front end input stage and Vas
It is always difficult to make a presentation which well balanced between maths à la textbooks and technical descriptions à la Self or Sloan.
I would suggest to add on your site some more technical desciptions of the front ends and Vas with relevant equations; it would be nice to see also descriptions with pro and cons of fully symetrical designs, fully ballanced design, folded cascode ones and better analysis of complementary Vas which is called in the litterature class AB amplifier.

Presentation of poles zeros graphs with respect to current, output impedance with respect to current for these stages would be very usefull.
I would love to see these aspects treated in the same simple way ( back of the envelope calculation) but audio oriented as Sansen in his book " Analog design essentials"

The presentation could be like he is doing, power point slides including circuit schematics and simple design equations for each circuit
Power point slides with more in depth equations of the different topologies would be a tremendous add on to the best book on audio amplifiers.

JPV

Hi JPV,

These are good suggestions, both for web site content and for the second edition, whenever it is done. It is especially helpful when people point out specific errors I have made or specific areas where my explanation has been difficult to understand, or where some additional math is needed to illustrate a point.

Cheers,
Bob
 
Book errata

Now that so many of you are reading the book, you may pick up some mistakes, like drawing errors, spelling errors, wrong words, errors in equations, etc. When you do, it would be very helpful to me for you to make note of them and send me an email to let me know about them.

As soon as McGraw-Hill runs out of the first printing, they'll do a second printing. At that point I'll have an opportunity to correct these errors.

Cheers,
Bob
 
Nicely Done!

Bob - Congrats on the book! Based on all of the positive feedback about it thus far, looks like I'll now have to buy one. Guess your heart is really in designing tube electronics compared to cutting-edge optical equipments...although you have demonstrated that you are able to excel at both!! - Best Regards Buddy, Ron
 
Hey Bob

I already have the "High Power Audio Amplifier Construction Manual" by Slone. Why should I buy your book?

Thanks,
Ted

Self gets it wrong also:
What's wrong with this picture? :)

I've not bought Self's or Slone's books, but I did buy Bob's.

A rather rude comment by you gripracer, how do you know that Bob's book does not have significantly more material?
 
Self gets it wrong also:
What's wrong with this picture? :)

I've not bought Self's or Slone's books, but I did buy Bob's.

A rather rude comment by you gripracer, how do you know that Bob's book does not have significantly more material?

*sigh* It's not a rude comment.

It's the question every consumer asks when they buy something. I want him to SELL the book to me.
 
Hey Bob

I already have the "High Power Audio Amplifier Construction Manual" by Slone. Why should I buy your book?

Thanks,
Ted

Hi Ted,

This is a totally fair question. First of all, I like Randy's book, even if it has a couple of mistakes (every book does, including mine). Randy's book is a bit more of a construction manual, as the title suggests. In fact, he is stronger than me in his focus in that area. For example, I don't provide printed circuit board layouts in my book.

The focus in my book is more on the part about deeply understanding audio power amplifiers of all types (except tubes). I try to start the reader off fairly easily, laying a strong foundation and providing a good mix of intuition and theory. Then I am able to go broad and deep without losing the reader. I don't cover just one topology and I don't dismiss any one technology out of hand. Indeed, I have a whole chapter on amplifiers with no or low feedback, even though I am a strong advocate of negative feedback. I also have 4 chapters on class D amplifiers. As a big advocate of simulation, I have two chapters on SPICE. I also have chapters on amplifier measurement and instrumentation for doing those measurements. I also have a detailed and practical discussion on ThermalTrak transistors, which I consider to be a major advance that reduces some significant bias stability problems with bipolar output stages.

I hate to sound like I am pounding my chest here, but these are some examples of why I think you would benefit from having my book AS WELL AS Randy's book. No one book is complete or the strongest in its coverage of all areas. I have Slone, Duncan and three different editions of Self. Each brings something to the party. If you only have Slone, the real question you should be asking is which one you should buy next - I hope that mine may fill that bill.

Finally, take a look at the table of contents of each book you are considering, looking for topics that you deem important that may not be covered in the books you already have, or in other books you are thinking of buying.

Thanks for asking. You are a good straight man. You gave me an excuse to pitch my book :).

Cheers,
Bob
 
Last edited by a moderator:
Self gets it wrong also:
What's wrong with this picture? :)

I've not bought Self's or Slone's books, but I did buy Bob's.

A rather rude comment by you gripracer, how do you know that Bob's book does not have significantly more material?

Hi PB2,

Guests cannot view attachments for this link. I can't see what is being pointed to.
Can you enlighten me?

Thanks,

David.