Can't find an errata concerning Cordell's book on his web page, would be great if there was an errata for the books offered in the same fashion D. Self have generously offered his readers.
The Audio Power Amplifier Design Handbook
The Audio Power Amplifier Design Handbook
There is not very many errors, I found the odd one but if you understand what he is writing, you can figure them out. I recall something in the ltspice section that differed when I was running the sim stuff. The beauty of this stuff is that you can sim the circuits yourself and measure the performance differences.
Hi Rob,
Unfortunately I will not make it to BA this year. Too much to do with the town home and the move. Spent most of the day today painting before I move in this Saturday. I've only got about 4 copies left myself.
Cheers,
Bob
There are always mistakes or explanations that could have been more clear. Many of the folks here have helped me greatly by pointing out these sorts of things. I have indeed learned a lot since the first edition came out in 2010, and, to the extent possible, have incorporated that into the original 31 chapters. There are also 5 or 6 new chapters, leading to a chapter count of 36 or 37, and from 600 pages to 750 pages. One of the new chapters is on switching power supplies and another is devoted to professional power amplifiers. The topic of noise has its own chapter now.
Cheers,
Bob
The second edition will sell for a very nominal price, probably in the $60 - $70 range.
Cheers,
Bob
I get about 10% of the price that they sell it to Amazon for. That's on the order of $3 on a good day. Don't quit your day job to be an author
. You pretty much have to do it out of a love of doing it. Technical books like these are a completely different paradigm from selling millions of copies of a romance novel.Cheers,
Bob
But how many romance books are read and re-read as many times as your book.
Looking forward to the 2nd edition too!Paul
Simple solution, add more drama to the book!
At that moment Cruxor was distracted by high IM distortion as the club's sound system blasted out the final chorus of "Highway to Hell”.... Bob stabbed him in the heart, and then pulled the bag from his cold dead fingers "Hmmm, genuine Toshiba JFETs" he mused...these are worth a fortune since they were discontinued, and everyone knows that they have excellent overload characteristics. Plus if you use a pair on the input you can double the S/N".
or
She ran across the lab and thrust her heaving breast against his manly chest.
"Take me now” she panted...
"Erm.., don't trip over the power cord to that Agilent Sr-500 distortion meter" he cautioned,
"I'd have to get it recalibrated if it falls...but they really are an excellent addition to any lab.."
At that moment Cruxor was distracted by high IM distortion as the club's sound system blasted out the final chorus of "Highway to Hell”.... Bob stabbed him in the heart, and then pulled the bag from his cold dead fingers "Hmmm, genuine Toshiba JFETs" he mused...these are worth a fortune since they were discontinued, and everyone knows that they have excellent overload characteristics. Plus if you use a pair on the input you can double the S/N".
or
She ran across the lab and thrust her heaving breast against his manly chest.
"Take me now” she panted...
"Erm.., don't trip over the power cord to that Agilent Sr-500 distortion meter" he cautioned,
"I'd have to get it recalibrated if it falls...but they really are an excellent addition to any lab.."
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Question about input current distortion
Maybe Bob Cordell has something to say, too, if he is watching this this thread...
A few years ago I read D. Self's Audio Power Amplifier Design Handbook Fifth Edition, and in pages 96 through 104 the author details the theme of "input current distortion" supported by many measurements that show how this kind of distortion can undermine the distortion performance of an otherwise low distortion amp. Significant worsening of a 0.001% THD at 1kHz were shown with source resistors bigger than a few hundred Ohms.
A few months ago I started to "design" (if I may say so) an 150W/8Ohm amplifier with two pairs of NJL3281/NJL1302 output transistors that evolved from D. Self's "blameless" amp and some ideas from this forum (mainly dadod's).
The input stage is the usual LTP with 10:1 degenerated BJT's that uses a 3mA current source, and a simple current mirror.
I simulated my circuit it in LTSpice, and was surprised that the effect of input current distortion was much much lower in the simulation than what is found in Self's book.
Well, I thought at that time, perhaps LTSpice doesn't account for something that plays a significant role in this distortion.
Now lately I also got Bob Cordell's book Designing Audio Power Amplifiers (2011 edition).
And wow, it's a really in-depth book on the subject, but I found no reference to input current distortion whatsoever.
So then I was thinking again: Self says that it is the nonlinear Ib (base current) that creates this distortion as it flows through the serial input resisitor (or the feedback network). Now LTSpice MUST account for that, don't you think? Isn't the exponential Ib-Vbe curve the basic equation of a BJT?
So this would be my question. Is it possible that the simulation is right that input current distortion is really not of major concern as long as I don't aim for ultra low distortion? But then what did Mr. Self measure in his book?
A nice puzzle to be solved. At least for me. I hope someone knows the answer, because I made the input transistors into two CFP's in my amp circuit to lessen the supposed effect of input curent distortion. But I would like to go back to the simple input pair, if the CFP input is not necessary. I would like a decently low distortion amp, but not an ultra low distortion one. Below 0.001% THD at 1kHz and below 0.01% THD at 20kHz would be fine by me... (I wouldn't like to leave out the RC filter at the input which has a 470R serial resisitor in it. That resistor would be able to raise the THD above 0.001% at 1kHz if Self's measurements are correct.)
Maybe Bob Cordell has something to say, too, if he is watching this this thread...
A few years ago I read D. Self's Audio Power Amplifier Design Handbook Fifth Edition, and in pages 96 through 104 the author details the theme of "input current distortion" supported by many measurements that show how this kind of distortion can undermine the distortion performance of an otherwise low distortion amp. Significant worsening of a 0.001% THD at 1kHz were shown with source resistors bigger than a few hundred Ohms.
A few months ago I started to "design" (if I may say so) an 150W/8Ohm amplifier with two pairs of NJL3281/NJL1302 output transistors that evolved from D. Self's "blameless" amp and some ideas from this forum (mainly dadod's).
The input stage is the usual LTP with 10:1 degenerated BJT's that uses a 3mA current source, and a simple current mirror.
I simulated my circuit it in LTSpice, and was surprised that the effect of input current distortion was much much lower in the simulation than what is found in Self's book.
Well, I thought at that time, perhaps LTSpice doesn't account for something that plays a significant role in this distortion.
Now lately I also got Bob Cordell's book Designing Audio Power Amplifiers (2011 edition).
And wow, it's a really in-depth book on the subject, but I found no reference to input current distortion whatsoever.
So then I was thinking again: Self says that it is the nonlinear Ib (base current) that creates this distortion as it flows through the serial input resisitor (or the feedback network). Now LTSpice MUST account for that, don't you think? Isn't the exponential Ib-Vbe curve the basic equation of a BJT?
So this would be my question. Is it possible that the simulation is right that input current distortion is really not of major concern as long as I don't aim for ultra low distortion? But then what did Mr. Self measure in his book?
A nice puzzle to be solved. At least for me. I hope someone knows the answer, because I made the input transistors into two CFP's in my amp circuit to lessen the supposed effect of input curent distortion. But I would like to go back to the simple input pair, if the CFP input is not necessary. I would like a decently low distortion amp, but not an ultra low distortion one. Below 0.001% THD at 1kHz and below 0.01% THD at 20kHz would be fine by me... (I wouldn't like to leave out the RC filter at the input which has a 470R serial resisitor in it. That resistor would be able to raise the THD above 0.001% at 1kHz if Self's measurements are correct.)