[Andre Jute]

Volumes from a broken set of the MIT Radiation Labs postwar conpendium
of all the high-level knowledge gaines in the war is currently being
offered on eBay, though the key volume for tubies is not included.
The key volume is:

Vacuum Tube Amplfiers, Vol 18 of the MIT Radiation Laboratory Series,
editors Valley and Wallman (hence most often referred to as "Valley &
Wallman"); commonly available in the Boston Technical Publishers Inc
reprint of 1964. Mine came to me about ten years ago as a gift from the
distinguished New York tubie Jeremy Epstein, I imagine he bought two
copies from Old Colony and sent me one; it is worth checking Old Colony
if you want one.

This is the most serious book about tubes ever written and it has
everything in it, including the SRPP (if you know where to look and how
to read the text (1)) and a great deal on constant current sources and
sinks (it's in the Chapter 11 on DC amps -- almost everything you want
is in Chapter 11, first place to look!), neither of which appear in the
RDH. If you have the RDH, Valley and Wallman, and the exceedingly rare
but very fine book Julian Bernstein wrote to teach from at the RCA
Schools (2), you would be hard pressed to name another book containing
as much as a solid page of useful information not in these three books.
Doesn't mean you shouldn't have plenty more books, but it does mean
that without Valley & Wallman, Fritz Langford Smith, and Bernstein,
your library will forever have a big hole.

I spent an entertaining eight or ten hours tonight, since my bath
before dinner last night (3), broken for dinner and a movie with my
family, reading Valley and Wallman on differential amps and constant
current sinks prior to signing off on the second version of my
electrostatic headphone amp, checking that I didn't overlook some
little thing that could wring out greater pleasure (I mean resolution,
of course!). Bless them.

Andre Jute
Visit Jute on Amps at http://members.lycos.co.uk/fiultra/
"wonderfully well written and reasoned information
for the tube audio constructor"
John Broskie TubeCAD & GlassWare
"an unbelievably comprehensive web site
containing vital gems of wisdom"
Stuart Perry Hi-Fi News & Record Review

(1) Allen Wright, for instance, claimed a dozen years ago in his book
on preamps that Valley and Wallman are innocent of SRPP; 'tis not so,
Allen, though admittedly the right bits are hidden among bits on heater
instability a guy who automatically specifies DC heaters had probably
never read.

(2) Bernstein contains the only comprehensive single-formula transfer
function for a complete amp I have ever come across, and he develops
all the math for it in the single chapter on audio amplifiers. (The
rest of the book is about filters, mixing desks, pads, and so on, all
the stuff techies knew back at the rear end of tubes until the 1960s.)
That formula explains why my amps almost always work brilliantly on
switch-on: I set the formula up as a speadsheet that draws me response
graphs and if they ain't flat, if the bandwidth isn't there, if the amp
won't be dead stable, and so on, I don't even start building it. If you
don't build the bad 'uns, you soon acquire a magical confidence in your
next amp! And if you start only with good amps, development becomes fun
rather than a souldeadening chore. It is not a crime to enjoy yourself,
and the sainted Mr Bernstein has made it easy for me. Only fifteen
years ago I knew less about electronics than at least half a dozen of
the diplomaed quarterwits on RAT.

(3) That's how it always starts. "I'll just read for an hour in my bath
before dinner." Ten hours later I put down the book, much wiser, but
nary a chapter, in fact no words, written of my own book under
construction. Tsch, tsch!