Bob Cordell's Power amplifier book

Dear Bob,

Mine arrived yesterday, too! I started to flip through the book and, whoa, a lot of plots I never seen else where! LS844 plots, the output stage plot shown up in this thread earlier and many, many more! Thanks a lot for such a nice book!!! Just by glancing through, I got the reason why there are so many people who chose BJT for input device. In Japan, most of DIYers pick JFET. I'll tackle error correction section later. I'd love to fully understand the concept and implementation.

This book is really precious to me with it's rich information in there. Yeeesss, it came to us, my precious....

Best regards,
Satoru
 
Dear Bob,

Mine arrived yesterday, too! I started to flip through the book and, whoa, a lot of plots I never seen else where! LS844 plots, the output stage plot shown up in this thread earlier and many, many more! Thanks a lot for such a nice book!!! Just by glancing through, I got the reason why there are so many people who chose BJT for input device. In Japan, most of DIYers pick JFET. I'll tackle error correction section later. I'd love to fully understand the concept and implementation.

This book is really precious to me with it's rich information in there. Yeeesss, it came to us, my precious....

Best regards,
Satoru

Hi Satoro,

Thanks for the kind words and I am glad to hear you got the book and have already paged through some of it. Even though plots can be a lot of work, I am a very visual guy and really appreciate them when I see them in a publication. They often help me to put the written words into context. I also am sometimes disappointed when some semiconductor suppliers don't show too many plots for their devices.

As you read further, you'll actually discover that I prefer JFETs for the input stages of power amplifiers. I actually discuss a JFET cascomp circuit that significantly improves the linearity of a JFET input stage.

Cheers,
Bob
 
Up to page 100 - thank you very much, Bob! I was a tech writer at Tektronix for 9 years, and I can say from experience as a writer the book is superbly written.

Not oversimplifying, nor trying to bury the reader in equations and associated proofs, but diving right into the subject, starting with a very generic amplifier and showing successive improvements step by step, with comprehensive SPICE information. And followed by in-depth chapters on various subtopics that invite the readers to pursue research on their own - phase margin and settling time with reactive loads being one of my own interests. This is one of the best electronics books of all time.

Next time I encounter one of those witless "all amps sound the same" people I'm going to challenge them to read this book, cover to cover, and see if they still feel that way after reading it. For more open-minder readers, particularly if they've never designed an amplifier before, this book will be a revelation. This book belongs on the "must-read" list for every serious audiophile or DIYer. If I had the power, I would force every reviewer to read it, and write about the product sitting in front of them, instead of a rehash of marketing talking-points.
 
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Hi Lynn,
Next time I encounter one of those witless "all amps sound the same" people
They still exist? No way!

I agree that reviewers should be forced to understand the subject matter. If they're going to publish an opinion on something, they should darn well understand the facts first.

Hi Bob,
No book yet. I'm feeling left out here a bit.
From the looks of things, your publisher should be pleased. This looks like something that will have a long term demand rather than a "best seller" type flash.

-Chris
 
Mine! Most interested in learning about SPICE and error correction, but I'm going to read the whole thing. My electronics knowledge is at the technician level, not engineering, so it's going to take quite a while. Hopefully I'll find the perspective I'm looking for on moving past the Leach design I've been listening to since the late 70s. I've enjoyed the books by Self and Slone, but you've moved onto new ground.

How will software be made available?
 
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Estimated date of delivery in France of my order through Amazon :
6th of november.

I can be patient, I have the Toole's book to finish, being currently only at page 61/550 !

By the way, as I ordered Bob's book, I look for other books which could interest me. Then I ordered two more : the Toole's and Newell &Holland's ones.

This last one is not specifically aimed towards DIY, but it may the best initiation to what are loudspeakers, to what they do and to what we must or may expect from them. For once, a high link is made between the recording process and domestic audio.

Two chapters with subjects, which I used not to be particularly keen on, "Horns" and "Loudspeaker behaviour in rooms" passionated me.

All the part following this last chapter till the end of the book was a real joy to read, I learnt much from it and I can't say being a novice in sound reproduction knowledge.

I strongly recommend it, it may enlarge or even change your view on audio at home.
 
Up to page 100 - thank you very much, Bob! I was a tech writer at Tektronix for 9 years, and I can say from experience as a writer the book is superbly written.

Not oversimplifying, nor trying to bury the reader in equations and associated proofs, but diving right into the subject, starting with a very generic amplifier and showing successive improvements step by step, with comprehensive SPICE information. And followed by in-depth chapters on various subtopics that invite the readers to pursue research on their own - phase margin and settling time with reactive loads being one of my own interests. This is one of the best electronics books of all time.

Next time I encounter one of those witless "all amps sound the same" people I'm going to challenge them to read this book, cover to cover, and see if they still feel that way after reading it. For more open-minder readers, particularly if they've never designed an amplifier before, this book will be a revelation. This book belongs on the "must-read" list for every serious audiophile or DIYer. If I had the power, I would force every reviewer to read it, and write about the product sitting in front of them, instead of a rehash of marketing talking-points.

Hi Lynn,

Thanks so much for what you have said. It's nice to hear that I may have hit the target. I really wanted to write a book that could be easily digested by those less experienced while really going deep into a lot of topics that I thought were important. Moreover, when you tell an ENGINEER that they have written something really well, that is REALLY above and beyond! :)

Thanks! I'm glad you're enjoying the read!

Cheers,
Bob
 
Whoever was the editor did a very, very good job. The hardest thing to achieve in writing is clarity and directness. As Mark Twain said, the difference between the right word and the almost-right word is the difference between lightning and a lightning-bug.

If you self-edited, that is astonishing. I can see the signs of much polishing in the text, saying the most with the fewest, and clearest, words. The organization is first-rate as well; I really like jumping right in with a sample amplifier and improving it in progressive steps, showing distortion data for every improvement along the way. By doing this, you demonstrate the distortion contribution of each section of the amplifier in a very clear and easy-to-understand way. Once the reader has a good understanding of how each section operates, and how to optimize it, then you move on to more specialized areas of amplifier design.

The discussion of how VI limiters momentarily convert the output of the amplifier from a voltage to a current source was an eye-opener; back-EMF currents from the loudspeaker then have nowhere to go, and can destroy a tweeter in moments. The relationship between phase margin, gain margin, and reactive-load sensitivity is something I wish audiophiles knew more about; these affect sonics, sensitivity to loudspeaker load reactance, and even the reliability of the amplifier.
 
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