Bob Cordell's Power amplifier book

do I really have to wait for my Christmas present?

I becoming that child searching around the house for clues and ruining the "surprise" element.

The longer this Thread goes on the more it reveals what is to come.
When we reach 600pages, then we will have two books to read.

Hi Andrew. I certainly hope you don't have to wait until Christmas! As far as I know, it comes off the presses this coming Friday, September 17. I don't know how long it takes to percolate through the distribution network, but I'm sure I'll have copies to sell at my table in the Atrium at RMAF.

Cheers!
Bob
 
The other option is to tie Mr Cordell to a chair for 24hrs of speech recognition interrogation.
But that wouldn't be very civilised (i could be mistaken), a couple of months waiting never hurt a DIY pervo.

Hey, you've seen the man, read his vertical words, now wait for the frggng book.
What better way to get the message across than,..........presto, in Italian : YouTube - hit the road, jack lucas!
 
Hi Bob,
Yes, the normal output of a sound card should drive an amplifier without too many problems. Messing around with the "volume control" is a pain in the behind, and most sound cards can put out an almighty "THUMP" when powering up or down. Changing sources can also create a heart stopping sound. An external volume control is therefore much easier to live with and places a control nearer to your work for adjustments. Since you are adjusting the input level to the sound card as well, not a bad thing.

If you end up with a buffer to drive the input of the sound card, you should have a lower noise floor as well. That would also keep the attenuation factors closer to what you calculate without trying to correct for an unknown input impedance. We know it's probably 10K, but what is it exactly?

-Chris

Hi Chris,

These are all very good points about interfacing sound cards. The convenience factor is certainly important. I think it is remarkable the amount of good SW there is out there for audio measurements. I wish we had it twenty years ago!

Cheers,
Bob
 
page 523, Figure 25.14 in my new book. 200 wpc balanced into 8 ohms, no NFB, ThermalTrak output transistors (8 pair).

Wowza, my 2nd Cordell amp project with +20year intergap.
Can't wait for DHL to deliver the book, i've got just the right driver-pre for the Thermaltrak train (i vote to reconsider the chair option).
Details, other active parts choice ?
 
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Hi Bob,
I think it is remarkable the amount of good SW there is out there for audio measurements. I wish we had it twenty years ago!
Heck! How about the internet in it's more mature form like we have now? Then there are these fantastic web sites where anyone interested in audio can exchange ideas with others in the field. Can you imagine how much material you could have reached?

Todays electronics enthusiasts are blessed in so many ways. The one thing I miss the most though are the kits and parts. Everyone was building something and stripping TVs for parts. I couldn't afford to buy many new parts at all. What I also miss were all the TV shops where you could get all kinds of things to play with in the form of unrepaired equipment.

I guess I miss quite a lot of things to tell you the truth. Of course, the extremely high prices for everything electronic isn't something I'm sorry to see go. $1 to $5 for signal transistors - each.

The only software I had back then was stuff I wrote myself to run on a PC. Programs for testing speakers to generate the T S parameters, and the sealed and ported box designer software. Response curves got pounded out in a dot matrix printer.

-Chris
 
Hi Bob,

Heck! How about the internet in it's more mature form like we have now? Then there are these fantastic web sites where anyone interested in audio can exchange ideas with others in the field. Can you imagine how much material you could have reached?

Todays electronics enthusiasts are blessed in so many ways. The one thing I miss the most though are the kits and parts. Everyone was building something and stripping TVs for parts. I couldn't afford to buy many new parts at all. What I also miss were all the TV shops where you could get all kinds of things to play with in the form of unrepaired equipment.

I guess I miss quite a lot of things to tell you the truth. Of course, the extremely high prices for everything electronic isn't something I'm sorry to see go. $1 to $5 for signal transistors - each.

The only software I had back then was stuff I wrote myself to run on a PC. Programs for testing speakers to generate the T S parameters, and the sealed and ported box designer software. Response curves got pounded out in a dot matrix printer.

-Chris


I cut my teeth on EICO and Heathkits in the Sixties. I started with the EICO HFT90 FM tuner, one of the very first FM tuner kits (if not the first). It was mono, of course, and I subsequently added the EICO FM stereo outboard demonulator kit.

Cheers,
Bob
 
How about posting the book's "Table of Contents" page, just to add to the anticipation.

Just how big is this book anyway?

Hi Kevin,

That's a great idea; I'll post it tomorrow.

The book is 608 pages and 31 chapters.

McGraw-Hill created the Table of Contents going down all the way to the bottom of the hierarchy, e.g., Chapter. Section, subsection, so the TOC is over 20 pages long. However, I've also created a smaller version that only goes down to sections of chapters for more ease of seeing the big picture.

Cheers,
Bob
 
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Hi Bob,
I did too. I built an IM-18 as my first kit and it still works fine. Since then I've repaired many Heathkit kits for other people, probably factory wired. Same for Eico kits, fixed many. I have also bought a number of audio products for my own use, the HF-87 being my favorite so far.

Bob, I have two HF-90A tuners sitting here (mine) for restoration later. Also an HFT-90, HFT-92 and HFT-94. Nice looking products. Do you still have your tuner?

A table of contents constitutes teasing those who have already bought your book! :) I'm sure it will generate additional interest. I bought your book without knowing of all this additional content. Even then I didn't have to consider whether it would be worthwhile or not. All I can say is that this looks like it may be another classic that is expected to be on bookshelves of enthusiasts. Along with several other recent excellent books by Doug Self and Morgan Jones. Probably more I don't know about. No, I don't yet have a copy of "The Art of Electronics". I'll have to fix that some day when I can afford it.

-Chris
 
Hi Kevin,

That's a great idea; I'll post it tomorrow.

The book is 608 pages and 31 chapters.

McGraw-Hill created the Table of Contents going down all the way to the bottom of the hierarchy, e.g., Chapter. Section, subsection, so the TOC is over 20 pages long. However, I've also created a smaller version that only goes down to sections of chapters for more ease of seeing the big picture.

Cheers,
Bob

Hi Kevin,

Here is the Table of Contents for the book:




Cheers,
Bob
 

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Cheezus! Looks like it covers just about everything there is to know!

:)

Hi Rikard,

I did try to touch on a lot that was relevant that I could think of. However, not all of those things are discussed at length (as you can tell by the page numbering in the TOC). My philospohy was to at least address those many things with at least some commentary so that at minimum readers would be aware that it is an issue, and maybe have a starting point for deeper consideration (even if they don't agree with my remarks). Many of those topics that I address only briefly are handled better in other (albeit sometimes scattered) places.

Cheers,
Bob
 
Thanks Bob, I can´t wait for the book to arrive! Will be great fun reading it and finally solve the last issues with my amp project, I´ve borrowed quite a lot from your EC amp for it and hope my slightly simplified version will be ok. (Designing amp with 2SJ201 and 2SK1530 in case you feel curious). It sims great except for some DC offset. Any comments would be hugely appreciated.

:)

/Rikard