books/resources for understanding about tubes and tube based designs?

[iandy4]

Hi All,
I've recently been ordering a lot of books and would love a few suggestions on what books to get regarding tube based designs.  I'm very interested in getting into building tube amps and tube preamps but I'd also like to understand what is actually happening in the circuits.  Thanks!

[R.G.]

Hi All,
I've recently been ordering a lot of books and would love a few suggestions on what books to get regarding tube based designs.  I'm very interested in getting into building tube amps and tube preamps but I'd also like to understand what is actually happening in the circuits.  Thanks!

The bible is the Radiotron Designer's Handbook, 4th edition. This was printed back in the Golden Age and my copy cost me about $150. It's been scanned and put on line somewhere. I hate reading whole books on line, so I can't help you with where. Actually, a better alternative is the RDH 3rd edition, which has a lot of the same info on basics, and is undervalued because of the encyclopedic nature of the 4th edition. My 3rd edition cost $9.00.

I think there's a CD version of the RDH4, too.

There are a lot of kindergarden reader versions of tube instruction on line now. I'm not current on where.

Before you spend a lot of money on this, go to Paul Millett's site where he presents scanned versions of Golden Age tech books. http://www.tubebooks.org/  and  click on the "technical books" link.

[Bill Mountain]

Check the Valve Wizard.  he has some cool looking books.

He posted this chapter from him preamp design book online:

http://www.freewebs.com/valvewizard1/Common_Gain_Stage.pdf

This is a quick easy read that explains a ton.

[davent]

These Norman H Crowhurst articles are based on hifi amps but they'll help get you started.

http://www.audioxpress.com/resource/audioclass/index.htm

The ax84 P1 theory document goes over the working of a simple two tube SE (single ended) guitar amp.

http://www.ax84.com/p1.html

dave

[defaced]

Another recent thread on the topic which has some good suggestions. 
http://www.diystompboxes.com/smfforum/index.php?topic=93043.0

[amptramp]

There is a whole galaxy of old books here:

http://www.audiophool.cjb.net/Techno.html

some of which are applicable but all are entertaining.  For really advanced understanding:

http://www.tubecad.com

[PRR]

All you need for the first decade is three sources:

Radiotron 3rd
Fender amplifier schematics
Frank's

Yes, all basic tube-audio can be well-designed from Radiotron 3rd, though it took me decades to realize that.

Since the 3rd cites now-obsolete tube types, digest as many Fender schematics as you can and look-up the tubes Fender used on Frank's. Turns out tubes-is-tubes, mostly the bases and type-numbers changed. 12AU7 is a mini dual hi-perf 6V type-56.

The 4th adds little basic information, but a lot of frills. Long chapter with many tone-controls, however just missed the James and Baxandal (you will see how close it missed).

3rd can be found in loose covers for $10. 4th is very impressive on the shelf and often fetches $100 in un-embarrassing condition. I have given-away my two 3rds and my 4th, read/refer them only in PDF.

Pete's site has both. You want to (gradually!) save and read much of this. You may start with Inside the Vacuum Tube (You didn't know electrons had legs? and you thought 3D was so 21st-century?)

Valve Wizard has some of the best new material around. If you are buying books, this is one.

Older Broskie (pre-2007) is very basic insightful no-BS modern design. Recently Broskie has moved onward onto new turf, and in my very personal opinion has become rather too clever.

[iandy4]

Alright! Thanks for the resources guys! I'll be buying the Radiotron 3rd edition as soon as I find it for around the price you guys mentioned.  In the meantime I'll find it in .pdf form.

[davent]

Abe books will find you a copy at a good price if there's one out there.

http://www.abebooks.com/

dave

[panterafanatic]

Alibris.com has some good deals as well. I do own the 3rd edition of Radiotron's, quite informative of what I have read. I have read all of the Valve Wizard's preamp book, absolutely great as far as learning how to set up stages and such, fantastic for the tube noob. I also picked up a copy of Graphical Constructions for Vacuum Tube Circuits by Albert Preisman which is great as well, very math intensive as far as understanding the physics behind tubes, but covers a lot of ground and I recommend picking up a copy for after you've read some other material. Slightly off-topic, but if you do visit P. Millett's site, check out Hi-Fi Furniture Design, I'm a couple hundred pages in, fascinating read if you want to learn more about cabinetry in general. Pentode Press has some neat info on their site as well. I'd like to pick up a copy of his books as well, from what I hear they are a good bit mathematical, too.

Lastly, goodwillbooks.com, quite a selection if I haven't already snaked all of the good titles  2.50 shipping for first book, 1.00 shipping for every book after that, thrift stores can be quite the gold-mine if you stop in every now and again, I've found multiple physics and calculus related books at my local goodwill for .50 and 1.00 per book.

[Dan Moos]

First off, if you are new, to tubes, the Radiotron book that is always touted is a bad place to start. You'll want it eventually, but there is way too much info in there for a newbie who just wants t get their feet wet to weed through. I'm not knocking the book, and my copy of RDH4 is one of my most valued books, but if I had started with it, I would probably have given up.

But, absolutely get Merlin's book "Desiigning tube preamps for Guitar and Bass". That book is what took me from cold beginner, to designing amps from scratch. His website is chock full too.

Once you have the basics down, there is a ton of stuff ot there. The TUT books are cool, but they are more like cookbooks than tutorials. All three of Richard Kuenals books are awesome, and I highly recommend his book on the Fender Bassman. He basically goes through the entire amp and anylizes it completely. Good way to learn the nitty gritty of an amp that basiclly spawened the genre.

But Merlin's book was essential to getting me to where I could get anything from tghose other fine books.

Also, join the AX84 forum. Good people that love to help.

[iandy4]

@Dan Moos  I was suspecting the radiotron might go over my head but oddly enough I had already decided to order Merlins book earlier today after reading about it (thanks Bill Mountain!).  Glad to hear it was a smart move!

Thanks for your help guys! I haven't built a signal tube based project yet but I can't wait.  If anyone suggestions for a good tube preamp to get started with, I'd love to hear (perhaps a favorite design in Merlins book).

[Dan Moos]

Go to ax84.com and do the p1 project. Its about as basic a tube-amp as you can get, and it is well supported by the community on that forum. It gets a pretty good rock distortion for only 2 tubes total.

[iccaros]

search on google for the US Navy NEETS module 6.

Really get all of their modules, best free education on all electronics IMO.

http://jricher.com/NEETS/

[Minion]

I have the RCA radiotron R-10 manual and I also have the Navy NEETS manual .... if you PM me with your e-mail I can send them to you sometime this weekend .....

[CynicalMan]

http://www.linear.com/designtools/software/#LTspice
http://www.duncanamps.com/technical/ltspice.html
http://www.duncanamps.com/spicevalves.html
http://www.intactaudio.com/forum/viewtopic.php?t=526

...if you're from the screw around until you figure it out school of learning. 

[mjones99]

Try also Jack Darr amp book.

[PRR]

> Pentode Press has some neat info on their site as well. I'd like to pick up a copy of his books as well, from what I hear they are a good bit mathematical, too.

Richard's books are EXCELLENT, but will NOT give the basic insight a beginner needs.

And just FYI: Richard's techniques are NOT how "Classic Tube" systems were designed. He uses a computationally intense (hard work) method rarely (or never) used by academics and certainly not by practicing designers until computer machines (PCs) were commonplace.

Now that there is a PC on every desk, this hard-work method does not mean days of work for each proposed condition. Still considerable set-up time before each millisecond of heavy PC math. And still limited by the accuracy of published data and the slop in published tube-curves.

In this I am echoing Preisman's thesis. In theory it is possible to compute every portion of every possible condition. But this means drowning in data, or squinting sparse data, then hard (setup and) computation. In practice, that's not needed. Assume you will find a nearly-linear result. A few rules of thumb lead to a possible condition. A few points on the curve tell the general magnitude of the gain and output, your first-order goals. A few more points tell the general magnitude of the distortion, your second-order goal. All of this can be done in under a minute on a bar-napkin.

In fact Preisman's approach, while over-formalized for the sake of the book, _IS_ how tube-system designers worked with unfamiliar problems.

For "familiar" problems (and 99.8% of everything audio-useful in tubes HAS been done before), we just plagiarize a Known Good plan, breadboard it, abuse it, and see where it leads. Read and understand every schematic you can find. Remember where you saw good ideas to use elsewhere.

[amptramp]

Another good source of both data and teaching is the older editions of The Radio Amateur's Handbook.  There is one good thing here - a lot of audiophile tubes are well-characterized and have now reached high prices, but transmitting tubes have generally been in production until later from domestic sources, are readily available on the surplus market and the prices have not reached the stratosphere yet.  The Radio Amateur's Handbook also gives good deigns for AM modulators (which are essentially power amplifiers with a high output impedance) using tubes such as the 6BQ6GT horizontal deflection amplifier tube in the 1956 edition.  These tubes are also plentiful and relatively cheap.  I converted a Traynor YVM-66 amp to 6BQ6's for a friend of my daughter who did not really care about getting the maximum power and the added plate caps look properly butch for this application, even if the output dropped from 35 to 25 watts.  And if she ever wants to go back to the full 35-watt power the 6CA7's gave her, I now have 6DQ6B's ready to go and they are not only a direct plug-in replacement, they take the same bias and screen voltages as the 6BQ6 and have additional transconductance in proportion to the additional current capability, so they work from the same drive.  6CA7's were going for $37 locally and this was getting a little too pricey for a casual player.  My 6BQ6's came in a fruit basket of about 20 tubes for $4 at the London Vintage Radio Club and they run best with a plate-to-plate load of 4000 ohms - information in the 1956 Radio Amateur's Handbook that you won't find in the typical audio design book.

The book contains chapters about power supplies and amplifiers (used as modulators) among other things with a lot of design data.  The newer editions have a lot of information about semiconductor devices and digital frequency synthesis, but much of the tube content has been dropped.  All editions also have a good chapter on building your own test equipment.

[amptramp]

Check out this site:

http://ampbooks.com/

It looks like these guys were reading your mind when you asked for tube design resources.