New book out on tube amps

[tubesornothing]

Richard Keuhnel from pentode press just came out with a new book on guitar amp power amps. Looks like it'll be a good one!

http://www.pentodepress.com/power-amp/contents.html

ton

[PRR]

> Richard Keuhnel from pentode press just came out with a new book on guitar amp power amps.

I have it in hand. At a quick flip: YES it looks very-very promising. The first chapter gets down to Basics, the type of "common knowledge" which is no longer common and which absorbs an awful lot of jaw-time in the Tube Amps section of the forum. He goes on to a good comprehensive tour of design thoughts. I know I will find something to grumble against, but Keuhnel gets things IMHO 99+% correct, which is rare in electronics and super-rare in guitar amp writing.

It is not "Bottles For Dummies". There's some math, you need to think while reading. However none of the matrix transformations which make 5F6-A hard to chew.

> about a product/book rather than tweaking a specific amp or a post about specfics of tweaking amps in general.

I disagree. This belongs in Tube Amp Building - Tweaks - Repairs.

Edit: I will defer to PRR's take on this! I had moved this out of Tweaks. I have now returned it.         With respect, Tubenit

[TubeGeek]

I ordered my copy yesterday.

[Ritchie200]

Pentode Press:
Vacuum Tubes - ok, that's a given.
Antenna Systems - HAM radio, yup.
Medieval Studies - ?!?!?!?!? ;D

Looks like a great book, must order....

Jim

[PRR]

> Medieval Studies - ?!?!?!?!?

It is a one-man shop. That man does not live by tubes alone.

It will take time to get through it. However I believe that this is a milestone in guitar amp studies. It is as comprehensive as any single book can possibly be. It sets a framework for further discussion.

I suspect it would be cool for Hoffman to sell this book. (Or since Kuehnel's deliveries are near as fast as Doug's, it might be fine for Doug to take the money, wire delivery info to Kuehnel, and settle-up at the end of the month. Beats double-shipping heavy books.)

[FYL]

It is a one-man shop. That man does not live by tubes alone.

A two-person shop: Richard is a techie, doing some improbable classified research for a living at EUCOM in Stuttgart. Irmeli is a highly respected scholar in medieval studies, she's got a PhD from U of Maryland.

It will take time to get through it. However I believe that this is a milestone in guitar amp studies. It is as comprehensive as any single book can possibly be. It sets a framework for further discussion.

My copy has been in the able hands of the USPS for the last few days...

[EL34]

Ooops, meant to move this to tools/tips.

[jhadhar65]

The Million Dollar Question...

...will it do for dummies like me who can mostly understand KOC, but for whom RDH4 needs a Rosetta Stone?

[sluckey]

And the 100 million dollar question....

Where will this thread be tomorrow? ::)

[EL34]

How about buy-sell-trade?

This topic will stay more visible here in a smaller board.

It will off the main page and forgotten in a day or two on the big board.

[tubesornothing]

The Million Dollar Question...

...will it do for dummies like me who can mostly understand KOC, but for whom RDH4 needs a Rosetta Stone?

I have both KoC and RK's new book and his preamp book.  RK is easier to understand and **much** better organized than KoC.  He does get a bit into the math and the graphs.  He also does equivalence circuits, which are theoretically very interesting, but I seem to go to the bench before really trying to understand that stuff.

ton

[osing]

I just recently bought Kuehnel's preamp book and am happy to see he also has written one on power amps, although I suspect it will take me some time to get through the first one.  I am always interested in finding other books as well - what are KOC & RDH4?

[TubeGeek]

KOC is Kevin O'Connor, not sure who the other is.

[HotBluePlates]

RDH4 is the Radiotron Designer's Handbook, 4th Edition. The 3rd edition is much easier to read, but also does not have much in the way of formulae to calculate the stuff talked about. The 4th edition is MASSIVE, some sections will make a genius' head hurt, but it gives the formulae to calculate things.

The problem with RDH4 is it is "the facts... just the facts" and as such can be difficult to understand because it doesn't tell you the context to make sense of what it presents. The are things that you'll read, and have a light turn on 10 years later because you finally have enough background to understand that the answer was in front of you the whole time.

[osing]

Thanks guys, I appreciate the info. I am still a novice, so I think I will hold off on the RDH4 book for a while then! Maybe when I succeed at understanding the bulk of Kuehnel's preamp and poweramp books I will look into RDH4. I do think that it is probably good to read several different authors, though.

[PRR]

> Maybe when I succeed at understanding the bulk of Kuehnel's preamp and poweramp books I will look into RDH4.

Read RDH3, the basic tube info and audio volt-amp and power amp and loudspeaker chapters FIRST.

It's free. It is small.

Kuehnel expects you to know this stuff.

> have a light turn on 10 years later

So I'm slow. Stuff I musta skimmed 40 years ago "clicked" only recently.

Hoffman may have the RHD3 and maybe RDH4 posted in a near future. Ants-in-pants can look for Pete Millett's site.

[EKDENTON]

The math is not so confusing as the terms or symblals for the parts of the tube  that is used in the math formulas especially the terms used  when you have AC and DC flowing.
 Just getting started with it but I like it alot so far. I am a slow reader and like to soak it in and mull it over in my mind  before moving on so it will take me awhile to read.

[osing]

>Read RDH3, the basic tube info and audio volt-amp and power amp and loudspeaker chapters FIRST.

It's free. It is small.

Thanks PRR - I didn't realize how old the book is and that is available for free. I did a google search for "Radiotron Designer's Handbook Pete Millett" and found it right away. He has v4 as well.

Thanks again!

[PRR]

> I didn't realize how old the book is and that is available for free.

Usta be, you HAD to renew US Copyright every 17(?) years.

The US 1972 Copyright act changed that. The details are really complicated. The effect is that anything published from around that time will be under full copyright for the rest of our lives, and probably longer. Basically the Publishers are subverting the system so they can keep profiting until the end of time.

But most tube books came up for renewal 1950-1970... the period when the Transistor was on the rise and "tubes were obsolete". So the copyright owner didn't file the paperwork and post the fee.

It isn't real clear when an unrenewed copyright turns totally Public Domain; depends what year, what kind of work it is. But both Raditrons are pretty clearly up for grabs.

The person who SCANS these lap-smashers can claim some copyright in the -scan-. Old Colony published RDH4 on CD, and you sure can't rip and post that version. But there are at least two other scans floating around, one apparently encouraging distribution and another clearly free for personal use.

Ah, look at http://www.el34world.com/schematics.htm about 1/4 of the way down the page
"Links to technical and amp service information."
"Radiotron designers handbook"

There is another scan of RDH4 broken into chapters. Since some of RDH4 is actually of little use, and all of it is a modem-choker, the chapters-version would be handy, but of course tedious to transfer to a server.

[Animatic]

I just ordered Richard Kuehnel's book based on the good reviews here.
I have some others coming, my reading list grows!
Thanks y'all.

[jjasilli]

I just ordered Richard Kuehnel's book based on the good reviews here. I have some others coming, my reading list grows!
Thanks y'all.

Ditto, except Amazon had a good deal on these Kuehnel books with free shipping; so I ordered them and will get the power amp book later:

*  Vacuum Tube Circuit Design: Guitar Amplifier Preamps
*  Circuit Analysis of a Legendary Tube Amplifier: The Fender Bassman 5F6-A, Second Edition

I've been thinking of building an 5F6, so this should be a good study.  Thanks to all.

[Animatic]

JJ, I am sure Amazon has a good deal,
but then again I have a nice email dialog going
with the author, and that beats free shipping any day.
D

Edit
I started Dl ing the Radiotron Designer's Handbook @ Pete Millett
right under it is a book entitled
'The Recording and Reproduction of Sound', Oliver Read, 1952,

Now THAT must be very drole in comparision to today's outlook.
This is before Les Paul did the early Ampex tube multi tracks.
Before ANY real understanding of most acoustics issue's solutions...
Many of the questions were still misunderstood then.
Almost before compressors and 3 band EQ.
Should be interesting.

I DID start recording on all tube equipment when I was quite young,
just as transistors were coming in. And there IS still a small audiophile
recording niche world that wants ONLY tube to tube analog to
1" TWO CHANNEL tape recordings and then to vinal.
But it is getting MUCH harder to actually FIND recording tape these days.

I still have an old Ampex 351 tube recorder needing a rebuild.
Another reason to join this forum.

[FYL]

Richard Keuhnel from pentode press just came out with a new book on guitar amp power amps. Looks like it'll be a good one!

It's a really good book, up to Richard's usual high standards, but with some of the usual US-centric errors. Vide p. 153 where attributes the ultra-linear design to Hafler and Keroes in '51, when it was invented by the great Alan Blumlein in '37: "Improvements in or relating to Thermionic Valve Amplifying Circuits", UK patent #496,883.

[Animatic]

[Duplicated from Duality thread]

Well I hit the mother lode of  Amp info today.

Richard Kuenel's Power Amp book came,
and it, in a cursory examination, is very clear,
and has lots of real world to theory comparisons.
It is ALSO about 3 months of technical school compressed.

At the same time a British book I had ordered earlier came.
Building Valve Amplifiers by Morgan Jones, Newnes Press.

Specifically a practical hands on guide book.
No substitute for serious electronics education,
but looks to be a very good bridge between
many questions and Richard's book.

Also lots of info on chassis tools and PCB boards etc.
Plenty of pictures to show Thai metal workers
with NO CLUE what I am saying...

I hadn't seen the Alan Blumlein reference yet,
 But I have been using Blumlein's figure 8 and Uni mic encoding
for a long time for stereo pair recordings.
The guy was one smart cookie.
The acoustic piano in some of the Slippery Island Blues thread
 is using Blumlein techniques to get the 'variable' room sound.

[Animatic]

I finished the book and have learned a WHOLE LOT.
Going to re-read it again at least once and keep it out as a reference.

Of course my 30 year old Algebra was not coming to mind too fast,
So i asked Richard some questions; he gladly answered.

Well low and behold a few weeks later he emails and says
he has now created an 'Algebra for Tube Amps Tutorial' on the website.

Here's link, very informative.

http://www.pentodepress.com/circuit-analysis/lesson-001.html

[tubes_are_us]

FYL is right. Alan Blumlein deserves the credit for inventing the ultralinear design. All that I can say in my defense is that a USPTO patent examiner should share the penalty box with me! I've posted my understanding of events here:

http://www.pentodepress.com/receiving/ultralinear.html

Just wanted to take an opportunity to set the record straight and credit Blumlein for what he rightfully deserves. It's unfortunate that we'll never know what greater inventions he would have created if not for his untimely death during the war.

Richard Kuehnel

[kagliostro]

 :)
Hi

it was a very very very long wait

I ordered the book the first days of the tread and it arrived at the end of june

mistaking I have asked to send it for mail

but now I have it and I begin to read

in this last weeks I have no much time because of job

but the book is really readable and explains the matter from foundations

this is a very good thing for me that am an absolute beginner

MANY THANKS to all they have advised about it

Kagliostro