Oops! Missed this reply. I'm in Cape Town, South Africa (bottom left, as Godfrey says).
Pic from CNN.com.
I bought it off Amazon. I never experienced the "problems" other people reported; I have always been able to order off Amazon. A few other people in SA have bought the book. I have also never experienced problems with the postal service, except that one time that they returned-to-sender some stuff I had bought locally.
I find the presentation quite different.
Cordell draws attention to a topic. Explains why it should be considered and moves on to the next topic. That I find disappointing.
Since I have only just started the simulation chapter, I think I may find the detail of adjusting and selecting component values buried in here.
If it is the case then the intro could/should have said "be patient".
As I only got the book on Saturday last, I've simply skimmed through it just now.
Given my enforced "holiday" today, I'm about to start my "slow" read.
I actually like the writing method you describe as it means it's reasonably easy to find aspects of design, without having to read reams of non relevant material to dig it out.
Different strokes, I suppose.
On simulation, I'm lucky enough to have National Instruments Design Suite at my disposal and that's fairly straightforward in use.
Some of the nuances in Cordell's book are very interesting and should seriously help to improve the distortion in my amp design from it's present 20kHz level of 0.05%.
Appreciated that we never know 'till it's built but starting from a possible 0.004% has got to be better than my present 0.05% (I hope).
My proposed Amp is for an "audio nut" friend who has a couple of Infinity Gammas that he feels he hasn't been able to drive satisfactorilly (they sound superb to me) and he "feels" he needs 2Ohm capability😱
Anyway, back to my reading 😀
Sandy
Hi,
I bought a copy of the book and have to admit it is far to detailed for me on alot of subjects and would therefore say it is not a book for novices as it claims on the back cover. There is also a great deal about amp design that is not mentioned. For instance
there is no mention whatsoever of pcb design, in general, or actual pcb designs of amp designs mentioned in the book. This would have been very useful if not essential to understanding the designs he offers. If you are a novice then buy one of Randy Slones books on amplifiers as they cover a more appropriate spread of theoretical and practicle subjects that include actual pcb designs for you to work with.
I'm sure that it is a very important book to those who have the relevant level of understanding to make the most of it, but it is not for me.
The book has been read once but now I see no need to keep it so if anyone wants it I can send it to you (UK only) for £20.00 including the postage. Or if outside UK I will send depending on actual postage costs.
Send me an email if you are interested.
Cheers
Cheers
I bought a copy of the book and have to admit it is far to detailed for me on alot of subjects and would therefore say it is not a book for novices as it claims on the back cover. There is also a great deal about amp design that is not mentioned. For instance
there is no mention whatsoever of pcb design, in general, or actual pcb designs of amp designs mentioned in the book. This would have been very useful if not essential to understanding the designs he offers. If you are a novice then buy one of Randy Slones books on amplifiers as they cover a more appropriate spread of theoretical and practicle subjects that include actual pcb designs for you to work with.
I'm sure that it is a very important book to those who have the relevant level of understanding to make the most of it, but it is not for me.
The book has been read once but now I see no need to keep it so if anyone wants it I can send it to you (UK only) for £20.00 including the postage. Or if outside UK I will send depending on actual postage costs.
Send me an email if you are interested.
Cheers
Cheers
If you sell this book instead of reading it again and again and again, you will stay a novice forever. 😀
Hi Andrew,
First of all, thanks for those corrections. For now the feedback site for errata is just to email me at bob@cordellaudio.com or audiohead7@yahoo.com. I do plan to eventually post errata on my website and may be able to have my son put up one of those email-in widgets.
Right now, my main priority is to get some of the supplementary book material up on the site. This will initailly include all of the device models used in the book and ready-to-run SPICE simulations for all of the tutorial examples. BTW, congrats on doing those SPICE runs!
Cheers,
Bob
I think we must accept that for some DIYers, the D in DIY means "do", and only "do", while for others it can also mean "design".
Just be happy that Bob keep the math to simple linear equations.
I've seen some things elsewhere that make me wish I paid more attention in math class. 🙂
David.
Hi Sandy,
I'm glad to hear that you are enjoying the book. I would caution, however, that the trusty 2N5551 and 2N5401 as VAS transistors should be limited to use in lower-power amplifiers where they will not be too taxed by power dissipation.
Cheers,
Bob
Hi Andrew,
This is good feedback and I'll try to improve this aspect in the second edition. If I understand you correctly, there are some topics where you would like me to dwell on them a bit longer and provide more detail. Also, that I should give more guidance on selecting component values.
Cheers,
Bob
I received Bob' book at about the 10th of october, read it fully and just finished it this morning. Time now to read and re-read chapters in a non-linear and very detailed manner.
When writing such a book, the author has to make some assumptions about what future readers should already know. I think that those would feel easy with Horowitz and Hill's book should not meet major difficulties with this one, bar maybe with Spice or class D.
Having a profound interest for solid state amplifiers since more than thirty years, I found that, even in the basics of the book, there were some subtilities I never learnt.
My prefered chapters were "Audio instrumentation", "Distorsion measurements" "The negative feedback controversy" "Amplifiers without feedback".
I am all in favour of global NFB, however it is interesting for an amplifier amateur to havec knowledge of circuits achieving high linearity witout it.
I just would have liked to see a few words about CFP differential stages neighbouring the Cascomp input stage.
About the NFB controversy, I underlined this, page 501, I think a great part ot the story relies here :
The early papers on TIM made much of the concern about the overshoot in amplifiers with low open-loop bandwidth. However it is clear that when an apples-apples comparison is done, the "overshoot" is really created by a major reduction in error as time progresses. The peak stress on the input mV and stage is similar in both cases (7 mV and 10 mV, respectivel), but the average stress is much larger in the case where open-loop bandwidth has been made large.
There is a topic which I slightly depart from the book view : it is classification of push-pull output stages. Bob does not forget to mention the semantic controversy about what should be called class B and what should be called class AB. There are some good reasons why this controversy exists.
I am not sure that linear audio amplifiers could be made class B if class B is defined as having precisely 180° of conduction angle. This would mean no quiescent current and beginning of conduction at above or below a few µV.
When young, I was very puzzled by the fact that op-amps output stages were said as being class B : how could they have low distorsion with no cross-conduction and no quiescent current, which was, and still is, the most current description of class B ?
Later, I understood that op-amps always have some quiescent current in their output stage, so I found the terminology as badly confusing. My strong preference goes for using the class B definition for any push-pull with quiescent current but without having a class A region where gm doubling occurs.
Regards.
When writing such a book, the author has to make some assumptions about what future readers should already know. I think that those would feel easy with Horowitz and Hill's book should not meet major difficulties with this one, bar maybe with Spice or class D.
Having a profound interest for solid state amplifiers since more than thirty years, I found that, even in the basics of the book, there were some subtilities I never learnt.
My prefered chapters were "Audio instrumentation", "Distorsion measurements" "The negative feedback controversy" "Amplifiers without feedback".
I am all in favour of global NFB, however it is interesting for an amplifier amateur to havec knowledge of circuits achieving high linearity witout it.
I just would have liked to see a few words about CFP differential stages neighbouring the Cascomp input stage.
About the NFB controversy, I underlined this, page 501, I think a great part ot the story relies here :
The early papers on TIM made much of the concern about the overshoot in amplifiers with low open-loop bandwidth. However it is clear that when an apples-apples comparison is done, the "overshoot" is really created by a major reduction in error as time progresses. The peak stress on the input mV and stage is similar in both cases (7 mV and 10 mV, respectivel), but the average stress is much larger in the case where open-loop bandwidth has been made large.
There is a topic which I slightly depart from the book view : it is classification of push-pull output stages. Bob does not forget to mention the semantic controversy about what should be called class B and what should be called class AB. There are some good reasons why this controversy exists.
I am not sure that linear audio amplifiers could be made class B if class B is defined as having precisely 180° of conduction angle. This would mean no quiescent current and beginning of conduction at above or below a few µV.
When young, I was very puzzled by the fact that op-amps output stages were said as being class B : how could they have low distorsion with no cross-conduction and no quiescent current, which was, and still is, the most current description of class B ?
Later, I understood that op-amps always have some quiescent current in their output stage, so I found the terminology as badly confusing. My strong preference goes for using the class B definition for any push-pull with quiescent current but without having a class A region where gm doubling occurs.
Regards.
It's been a few years now since I read that book... I don't recall Self having explicitly explained the difference between his (high-bias) class B and class AB.
Hi Edmond Stuart, davada,
I cannot think of anything more tedious than reading a book again and again and again just so I can say that I am no longer a "novice" at amplifier design. I would go to college to do that, and do it properly.
You will have to accept that some people (like me) just do not need to have that level of detailed understanding. Other people like yourselves thrive on it and that's fine and dandy.
I'm quite comfortable knowing when I reach the limit of where I want to go with any particular subject. This book is not for me and hence wasted sitting on my shelf.
Cheers
I cannot think of anything more tedious than reading a book again and again and again just so I can say that I am no longer a "novice" at amplifier design. I would go to college to do that, and do it properly.
You will have to accept that some people (like me) just do not need to have that level of detailed understanding. Other people like yourselves thrive on it and that's fine and dandy.
I'm quite comfortable knowing when I reach the limit of where I want to go with any particular subject. This book is not for me and hence wasted sitting on my shelf.
Cheers
Makes me wonder why you bought it in the first place, overzealous ?
At university i've had 14 math classes, several on vibrations and sound, finite element analysis, waves theory, system dynamics (N+P feedback, simulation theory), general and power electronics (think : generators on ships, SMPS, voltage transformation, wiring, rectification, efficiency numbers, electric drive systems, design of main switch boards)
On top of that ; analog audio amplifier classes, PCB designing, simulation software, hundreds of nocturnal hours on the university main frame to run simulations, plus hundreds of hours in the electronics faculty library for books and magazines on audio.
There are several people at this club who did study (general) electronics, and still don't even get the basics of an amplifier up till this day, see the BT thread for the latest example.
Sorry mate, even if you have no desire to become an ap-sys customer as moi, you still need to fill your shelfs to get any further than stuffing breadboards the rest of your life.
(On top of that i find it highly disrespectfull to Mr Cordell to post used item offers at this thread, even a neanderthal degenerated prick as moi has better manners)
At university i've had 14 math classes, several on vibrations and sound, finite element analysis, waves theory, system dynamics (N+P feedback, simulation theory), general and power electronics (think : generators on ships, SMPS, voltage transformation, wiring, rectification, efficiency numbers, electric drive systems, design of main switch boards)
On top of that ; analog audio amplifier classes, PCB designing, simulation software, hundreds of nocturnal hours on the university main frame to run simulations, plus hundreds of hours in the electronics faculty library for books and magazines on audio.
There are several people at this club who did study (general) electronics, and still don't even get the basics of an amplifier up till this day, see the BT thread for the latest example.
Sorry mate, even if you have no desire to become an ap-sys customer as moi, you still need to fill your shelfs to get any further than stuffing breadboards the rest of your life.
(On top of that i find it highly disrespectfull to Mr Cordell to post used item offers at this thread, even a neanderthal degenerated prick as moi has better manners)
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Hi Bob,
many thanks for the personal reply.
I note your commernt above, Re. low power use of the 2N5551/5401 transistors and my intention was, as per your higher power amp version in the book to utilise higher power devices as drivers, etc.
However, would you be so kind as to clear up something that's driving me crazy, Re. the Darlington VAS configuration.
As you so clearly say, this VAS stage is a pseudo "Darlington" with the Collector of the primary transistor connected to ground (0V), rather than the Collector of the secondary transistor and "you would explain the reason for this shortly".
I have read the ensuing paragraphs and chapters 'till my eyeballs hurt but I'm damned if I can spot this explanation.
I do admit that I tend to "speedread" but it's driving me nuts to find the explanation.
Pretty please, put me out of my misery?
Sandy
Well, he didn't say he'd use it to clean his private parts, he just didn't find it useful. Don't think he'd hurt the author's ego in any way. Another culture, different ways. In this case - practical ways.
some folk will not invest time in their hobby/ies.
A golfer gets better by practicing.
A chessplayer gets better by practicing.
An Audio DIYer gets better by practicing.
Choose a hobby where you enjoy the practice part, or having sampled, move on to try a different hobby.
I dance, I practice, I get better, I enjoy the practice.
Well, you will have to believe me when I say "I get better". Ask the Ladies for an unbiased opinion.