Make your own free website on
The Tube Amp Hall of Fame  |     home
Tube amp hall of fame #1   |   Tube Amp Hall of Fame #2   |   Tube Amp Hall of Fame #3   |   Tube Amp Hall Of Fame #4   |   Tube Amp Hall of Fame #5   |   Tube amp hall of Fame sites 1 to 9   |   Related Links   |   Contact Me
Related Links

The Book

Inside Tube Amps by Dan Torres

Search for Tube Amps--      EBAY <<click on that

 Amp Companies

 SAS Audio Labs

Mesa -

So Flo

he'll be up soon!

 AMP Modification Companies
Awesome Mods and Hand wound Pickups

Marshall Mods from Heaven,
kt88's so nice

(We specialize in modifications, restortations and custom built tube amps.
We are just as obsessed with tone as you are and whether you are looking
 for a high gain amp or a beautiful clean amp,
we can get you the tone you are looking for ) Thats from them!!

Tube Data Sheets

American and European -number replacements

Slyvania Tube Charts from 1959
the home site
Thank you , Bill Beech
his site

el34 data
6l6 data
12ax7 data
I use these guys alot!!!!

Ruby Tubes

Fundamental Properties of tubes

 Basic Tube outlines

Dont forget  My  other  web site
Speakers for Everybody
 for some awesomespeakers

Speaker Repair --


 for Chokes and Trannys output and power.
Excelent stuff here. High Quality
All things CryBaby Pedals

Parts and stuff ;  (Mustard caps)

Just click on what you need
Magic Parts

Speaker Repair --

Triode Electronics Home Page and World HQ

Just gobbs of them here


Lots here

try the duncan site

DR Tube

and pats site

worldwide Check this out!!!!

otherside of the planet

Diy audio sources at

Free guitar stuff

Lots of schemstics one of my favorites here
Cool Schmatics

 Misc Cool Stuff
Frank's cool site, w/all kinds of stuff on Tubes

Tube numbering Systems

The absolute beginnings of Tubes-
Read all

cool stuff
The Best Military Films
Cool Flicks
Radio Afghanastan

The wonderfully simple Manley SE/PP 300B "Retro" directly heated triode is
virtually Lee De Forest's very first evolutionary 3-element piece,
comprising only filament, input grid and anode output. Brought to reliable
perfection by Western Electric USA and later by Standard Telephones UK as
the 4300B, the 300B was very much intended and widely used for telephony
amplification. But audio enthusiasts of older times knew a good thing when
they saw (heard!) it and the great love affair between the 300B and music
began... and dwindled many years later as the American Western Electric
300B was taken out of production in the late 1980's making the genuine
ones extremely valuable and, accordingly, very highly prized as
collectors' pieces. With the Asian-driven passion and resultant revival of
SINGLE ENDED topology the call for the 300B to be put back into production
was too overwhelming for the Chinese factories to resist. The Soviets and
the re-start of USA manufacture of the genuine Western Electric original
have further expanded the selection. Basic thermionic simplicity...
directly-heated triodes... it is a drug for some, a religion for others...
With its decidedly (and studiedly) 'retro' physical proportions- very deep
front-to-back dimensions with a narrow side-to-side width, this layout
closely follows concepts of a bygone era, where the well-conceived
intention was to keep the power supply as far as possible from the hum and
noise susceptible octal input tubes. The output tubes themselves require
careful distancing from the mains transformer and, of course, require pure
DC on their filaments. Again, reverence to past times begs the use of
vacuum tube rectification with its very gentle voltage rise-time. But to
bring the performance up to modern demands, we use two rectifiers to
enable the use of very substantial filter / reservoir capacitors... over
1300 microfarads in the B+ rail- much improved from the 4 or 8 microfarads
utilized in the 1930's.
When several other manufacturers started selling single-ended amps with 5
to 9 watts of power, we understood subjectively and objectively the good
part of the story: the superb mid range, the delicate detail, the inherent
simplicity. The bad news was that there were almost no speakers efficient
enough to help form a dynamically viable system. The worst news was that
either these single-ended amps cost more than the condo and or they had
specs that could only be read as a joke. As the triode fans increased,
more efficient speakers became available and several fanatics began to
dismiss push-pull as a bad thing to be avoided at all costs. We objected
to such blanket generalities and stressed that the push-pull done right
with truly phase-balanced transformers, quality parts throughout and well
designed circuitry has proven to be a superb technique. We also enjoy
single-ended topology but only when it is done right, mostly because we
expect flat frequency response and low distortion out of an amplifier. We
knew that we could achieve this in a properly conceived single-ended
design. David chose to rise to the challenge of designing special
circuitry that could be switched "on the fly" From 18 watts in parallel
SINGLE-ENDED (class A) to 36 watts in PUSH-PULL (class A/B ) which, we believe is unique in the industry.
The Output transformer (hand-wound in our own factory) is of complex
design employing inordinately high primary inductance to compensate for
the mandatory magnetic "gap" required for the uni-direction current and
voltage flow of the single-ended output stage. Another factor in the
single ended triode saga (currently enjoying a wide spread popularity) is
demand for little (or sometimes zero) negative feedback. We at Manley Labs
believe in the judicious or sensible amount of feedback to refine and
maximize performance. Our 300B 'retro model' gives you the choice in
precision switched 1 dB steps to go from ZERO dB's to 10 dB's of negative
feedback. Even with zero negative feedback, this amp is cleaner and
flatter than any single-ended amp we know of. For more information about
variable feedback read "Notes on Negative Feedback".
One interesting aspect of negative feedback is it gives a higher damping
factor. Conventional wisdom would have us think that the higher the
damping factor, the better. Our experience is that the optimum damping
factor is not infinity and that it depends on the speaker, the room. and
the taste of the listener. In other words, the optimum is variability, and
this we provide. This amp satisfies us as long time amplifier builders,
amazes the critics in several well known magazines and is bound to satisfy
the you with the ability to fit into your system and your expectations.
BUT REMEMBER PLEASE the overall facts of power ratings versus loudspeaker
sensitivity and room size when electing to venture into lower power
amplifiers (less than 50 watts) and especially when contemplating
single-ended topology. Please read "Considerations of Amplifier Power" for
more info.
The "RETRO" SE/PP 300B (1995-2000) has been DISCONTINUED.
It has been REPLACED BY NEO-CLASSIC SE/PP 300B 11/2000.
We also used to build a Compact SE/PP 300B design (1995-1997) which used
solid state rectification and a 12AT7 / 7044 input/driver stage.
These Compact SE/PP 300B's now reside in the mausoleum as well.