Bob Cordell's Power amplifier book

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Fair enough, but all the books and manuals were mine. I won't write in any book, manual or any other original documentation. When I started at the calibration lab, they had the same rules for the same reasons.

I wish that some of the challenged individuals I hired over the years had your ideas. You wouldn't believe how common writing in a book is and it is considered acceptable. This is admittedly a sore point with me. That and they didn't use pencil, pen and highlighters.

Signing a book and dedicating it to someone is different. Otherwise writing in those things should be a taboo.
 
Hi Mark,
My training was to never write in books, manuals or on schematics. Not ever.

I used to photocopy (remember that?) the section and write on that, then include it in the service manual or book. Same for other notes and corrections. Today I print the area from a PDF if I don't have the original, mark the copy and scan it back in, including it in the same directory. Scanning the original manual or book always had higher resolution.

It happens the "correction" isn't always accurate or the best way to do something. If you write on the original, you have no back-out plan. Also, replacement parts can become unavailable. If you've marked those in you have to cross them out and write something else. What a mess. You're way further ahead to leave the documentation untouched, pristine. That way you can document design progression and go back when required. Factory update information wasn't always accurate either.

In my shop, one cardinal rule was to never write in a manual or book. Otherwise that person had to pay for a new one immediately. No exclusions ever.
Well, I used to be like that, not marking books ever. However, I soon realized that I will probably die at some point and these books will either be sold for next to nothing or they will be donated, so I prefer to write something in a book rather than having to read the same section a couple of years afterwards and then start scratching my head whilst saying "How the hell did I figure this out back then?" Also, if we are talking about new books, I sometimes completely deface them and, after I have studied them well enough, I will buy new ones. If we are talking about rare books from the 40s, 50s and so on, then I tend to be more careful and will avoid writing anything in them.

Also, many of the books I buy are used, and they have already been marked by someone back in the 60s during their college years or whatever... Many have the original owner's name written in it, one of them was even autographed and dedicated by the author to one of his students back in 2002 or so; apparently the student didn't care too much about it to actually keep it.
 
The DAC I have is a Benchmark, and I believe it is extremely well-executed.
I had a Benchmark DAC-3. Then an original Topping D90 (with AK4499EQ). I studied the architecture Benchmark used for DAC-3, and tried to make a dac that sounded as good. This was when I was first learning. Eventually I made a dac similar in architecture to DAC-3, but I converted PCM to DSD in hardware using AK4137. That dac sounded better than DAC-3 in some ways but not all, and I was encouraged to sell it commercially. It was too complicated to sell, and it didn't sound better than DAC-3 in all ways, so I let that dac project go. Later I got a Topping D90, the original one, and an AK4499EX eval board. D90 easily sounded better than the Benchmark, and soundstage was better too. This was using electrostatic speakers from Sound Lab. Once I realized how DAC-3 really performed, I gave it away to my daughter. The D90 got loaned out to a friend, after I reverse engineered to learn what I could from it. I learned a lot from modifying the AK4499 eval board too, and mostly running it in DSD volume bypass mode.

Given Benchmark DAC-3 as a starting point there really are better sounding dacs that reveal more detail that is on a CD than you ever heard before through DAC-3. Bruno Putzeys' Mola dacs probably fit into that league. Even Holo Spring 3 dacs are better than what you have. What I have is probably closer to Bruno's dac, except I don't have SOA sigma-delta PWM yet.

If you ever get out in this part of Northern California, I'm in Auburn, a bit North of Sacramento. You are cordially invited to visit. Most of the time the dac here is up and running, but not always. Its an experimental prototype. A pic of the test setup is in my dropbox at: https://www.dropbox.com/scl/fi/2u4e...etup.jpg?rlkey=b0k9o2yxkserprl89y9s8prs7&dl=0 Anyway, please do bring your Benchmark or whatever you have. I promise you will find it interesting and informative.
 
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Yeah, many of the old books I get have been written in. That's too bad.

From my point of view, I am merely the steward of books I have. If they are tossed when I pass, okay. But I would hope my kids respect the knowledge enough to pass them on. It's what I do that is important and I can't control what the next person does.

Anyway, Bob's books are unmarked as are everyone's, including the Linear Audio set. You may find sheets of paper inside where my notes are, but that's it. I don't have the problem where I have to scratch my head. The best part is that sheets of paper that are loose demand attention and I often find what I need there.
 
I get what you are saying. In my case I have no kids, no wife, no nephews, no girlfriend, no nothing, and my only brother is a businessman; I doubt his kids (if he ever has one) will be interested on my Network Synthesis books from the 40s. Now that I think of it, that is probably why I have around 3000 books....
 
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Hi Joe,
LMAO!

Well, mine are technical and have historical significance. There are many out there, same books and manuals but they are getting scarce. I have no idea how many books I have, probably scary!

My good friends and daughters have been made to understand they have value to someone out there. Not monetary so much as historical information. Even something as commercial as a service manual for a Marantz 2325 that is unmarked has value well beyond Ebay. When I go, I want these to go to someone who needs and will use them. When I begin winding down I will start distributing them so others don't have to deal with them. I hope by the time I pass, all my parts and equipment are already gone.
 
Yeah, I understand what you are trying to do, and I think it is a good call.

Also, I'm pretty sure that if my hypothetical descendants decide to sell each individual book on eBay, they would probably get a good deal out of it. However, that would involve a lot of research and time that I bet they wouldn't be willing to take.

By the way, I could be wrong here but, after I die, they can set all of my stuff on fire, for all I care.
 
I had a Benchmark DAC-3. Then an original Topping D90 (with AK4499EQ). I studied the architecture Benchmark used for DAC-3, and tried to make a dac that sounded as good. This was when I was first learning. Eventually I made a dac similar in architecture to DAC-3, but I converted PCM to DSD in hardware using AK4137. That dac sounded better than DAC-3 in some ways but not all, and I was encouraged to sell it commercially. It was too complicated to sell, and it didn't sound better than DAC-3 in all ways, so I let that dac project go. Later I got a Topping D90, the original one, and an AK4499EX eval board. D90 easily sounded better than the Benchmark, and soundstage was better too. This was using electrostatic speakers from Sound Lab. Once I realized how DAC-3 really performed, I gave it away to my daughter. The D90 got loaned out to a friend, after I reverse engineered to learn what I could from it. I learned a lot from modifying the AK4499 eval board too, and mostly running it in DSD volume bypass mode.

Given Benchmark DAC-3 as a starting point there really are better sounding dacs that reveal more detail that is on a CD than you ever heard before through DAC-3. Bruno Putzeys' Mola dacs probably fit into that league. Even Holo Spring 3 dacs are better than what you have. What I have is probably closer to Bruno's dac, except I don't have SOA sigma-delta PWM yet.

If you ever get out in this part of Northern California, I'm in Auburn, a bit North of Sacramento. You are cordially invited to visit. Most of the time the dac here is up and running, but not always. Its an experimental prototype. A pic of the test setup is in my dropbox at: https://www.dropbox.com/scl/fi/2u4e...etup.jpg?rlkey=b0k9o2yxkserprl89y9s8prs7&dl=0 Anyway, please do bring your Benchmark or whatever you have. I promise you will find it interesting and informative.
Thanks! I don't get out to that area of CA very often, but thanks for the invite. It sounds like you have a lot more hands-on experience than I do.

Cheers,
Bob
 
That shelf thing sounds like a great idea! Unfortunately, the picture is not shown, it shows a broken link.
I don't know why it doesn't show up for you, but here it is attached.
 

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