Welcome to my personal webspace
Just knock on the doors of "Tube-Perception"
Here you enter a realm, where warm glowing Tube filaments
and valence electrons, are set free, in electrical motion
these minuscule electrons, are leaping across a vacuum
attracted by charge, from rare earth metallic combinations
amplifying sound, creating music, and lifelong memories
TDoor I - My hand crafted ShermanAudio amplifiers
Door II - Many old Classic Tube Amp restorations & their schematics
Door III - Some loosely written loudspeakers notes
Door IV - Tube Amp Manifesto "The Una-Tuber"
Door VI - My contact information
Door VII - Very Important Hazard Warning
Door VIII - About the very basics of Tube measurement
Door IX - a Hammond/Leslie/Wurlitzer webspace
(Partly under construction, I let a few things make it here)
Door X - Schematic Vault
(Totally under construction now, your patience is very much appreciated)
A glass of Merlot, in a cheap Glass, some Classic Rock
Synergy, relaxation and Nostalgia
Old Bands never die, they just break-up, quit, retire or just fade away
But the music they create, is eternally part of the human archeology
As long as the Vinyl doesn't melt
My totally "biased" Audio Power Tubes Opinions - hold the flames please!
Hi-Fi, Guitar, Bass, Organs & Radios
KT-88/6550 - Cavernous lows & very polite highs, that trash metal crunch, surprisingly good with Horns and Lowthers
KT-66/6L6/5881* - Layered, tonal, great for both HiFi & Guitar Amps, many nice variants, the chameleon of Tone
SPECIAL HONORABLE MENTION IS THE 7355 TUBE* (RIP) - Small 6L6 variant, brilliant design, out of production (eg. Harman Kardon)
KT-77/EL34/6CA7 - Midrange Guitar "screamer", with a nice leading edge, crystal clear HiFi, very nuanced, KT77 smoothest
EL-84/6BQ5 - Musically engaging, great for Classical Music, a smooth operator, vocals are crisp and clean
7591/7591A/7868/6GM5 - Sweet sound, deceivingly smooth at high power, can kill speakers, current production is Russian
7027A (RIP) - Nice Warm & Detailed Sound, used when Tubes roamed the market
8417(RIP) - Audio Power Pentode, late bloomer, akin to a V8 and Oil Price Hikes, long out of production
6F6 Russian (US RIP) - In old Car Radios, absolutely fabulous tonality, a best kept DIY secret, listen here on 16 Ohm PSV-2
https://www.youtube.com/watch?v=bTS7HkzkWhE
6V6/7408 - Lighter version of 6F6 but different sound, filaments are not as hungry as 6F6, can be bright, glassy-clear
6AQ5 (RIP) - Out of production, have a few on hand, will made a prototype amp, with plans to enjoy later
6CM6 - (RIP) also out of production, fantastic Jazz and Vocal, listen... a small 6V6, similar sound character, glassy-clear
https://www.youtube.com/watch?v=zrj1FGQ7e5Y&t=1s
E80L/6227 (RIP) - European 9 Pin Pentode. 10,000 hour PQ version, on my short list of Tubes to use, uncommon
2A3 - Single Ended Holography, Fine Bourbon & Single Malt Scotch, look for the Single Plate Sovtek
300B - The trusted voice of pure Class A - the golden S.E. standard - Expen$ive but Musical, used in Preamps as well
Special Mention Power Tube;
6146B - Commonly used for Radio Transmitters, used in Audio Amplifiers, bully of the block. Capable of 100W in PP
My totally "Subjective" Small Signal Voltage & Gain Stage Tube opinions - because I can
Line Stages, Tone Controls, Phase Splitters & Buffers
ECC83/12AX7 - High-Mu, Dual Triode everyone knows something about, it is very common in Audio
ECC81/12AT7 - Medium-Mu Dual Triode, common in Guitar amps, seen less in HiFi amps (Fisher SA300)
ECC82/12AU7 - The true 9 Pin chameleon, Low-Mu, versatile, ubiquitous, handy, the toolbox of small signal tubes
12DW7/7247 - Half of a 12AX7 plus Half of a 12AU7cool tube (Dynaco S35, EICO 2036), nice tube
ECC88/6DJ8/6922 - Frame Grid design, a Love/Hate HiFi reputation, I love'em Hot and Bothered (Audible Illusions)
ECC85 - Used sparingly in Audio, very sweet, much more common in German Amps (Grundig)
EF86/6267 - A small Pentode Tube, everyone needs to listen to, most never have (Mullard 5-20)
6C4 - This is half of a 12AU7, small and petite, very cute, used in Hammond AO-28 Preamp (RIP)
6SN7/5962 - The bulldog of Small Signal Gain Stages, robust and musical (Cary Audio SLP-5)
6J5 - This just half of a 6SN7 (think 6C4), killer tone, a best kept secret, out of production (RIP)
6N7 - Rare metal audio tube, Stromberg Carlson Theater Amps (Stromberg Carlson APH50)
6SL7/5961 - Less seen in amps, Cary Audio used them in the 90's (SE300)
12BH7 - Robust dual triode, awesome & beefy, great good driver tube (Hammond AO-28)
ECC99 - The new kid on the block, speaks with an accent, nouveau 12BH7 (JJ Electronik)
6C45P - A best kept secret for Phono Stages, used in DIY for those in-the-know (Transcendent Sound)
6N1P - More robust than a ECC88/6DJ8, great driver for DHT Triode Tubes (ShermanAudio Kismet)
7199 - Out of production tube (RIP), Pentode/Triode, Russian version so-so (Dynaco ST70)
6AN8 - Out of production tube (RIP), Pentode/Triode (Dynaco MK3, some Japanese Amps)
My "preference" for Tube Rectifiers, here are the unsung heroes who work in the engine room
"The unfair reputation" when it comes to music, Tube Rectifiers absolutely rule the tone department.
I hope to launch a Tube Rectifier revival.... QUIET, Shhhhhh, prices will skyrocket.
GZ34/5AR4 - 5V/2A Superman of tube rectifiers, general purpose (Dynaco ST70)
GZ37 - A somewhat filament hungry 5V/2.8A variant of the GZ34, British, rare & expensive
Type 80 Globe - Paleo Rare Tube Rectifier, too much for me as well, for museums
5Z3 - Also rare, museum stuff, not for DIY, unless there is extreme nostagia
5Y3/5Y3GT - Neutral 5V/2A, very reliable when operated within their maximum ratings, quick-on
6X4 - Lighter 6V/.6A version rectifier, mostly used in Preamps (Scott LC21)
5V4 - Rare now, 5V/2A sweetie, nice for medium powered amps 20 to 30w
12X4 - A 12V/0.6A version of a 6X4, same tube, different filament (Dynaco PAS)
6CA4/EZ81 - Like a 6X4, but not as popular, 1amp, think VOX (Leslie Reverb Cabinets)
5U4/5U4G - Robust Rectifier 5V/3A, tall, dark and handsome (US Navy)
5R4GY - That Sexy glass bottle, 5V/3A often seen with Brown Shorts (JAN)
5R4WGB - Potato Masher Rectifier, totally ready for Dinner and Battle (Military Grade)
6AX5/6X5GT - Popular 50's-60's 5V rectifier, similar to 5Y3 in ratings, 5V/0.6A from the 50's
274B - Western Electric, high end tube, available today, must be nice, Expensive as F, $$$
ShermanAudio
Tech Note - SA.TN01 on Vintage 7189 amplifiers
EL84/6BQ5 is not always a substitute for 7189
NEVER replace a 7189 with an EL84/6BQ5 in a true 7189 amplifier....
Unless, the Amp was designed for EL-84/6BQ5
7189 RULE OF THUMB
If the socket, instruction manual or schematic says; 6BQ5/EL84/7189
YES... both tubes are compatible
If the tube socket is labeled only 7189
STOP
You will toast the amplifier, output transformers or both
The images above are borrowed from Duncan's Amps
Duncans Amps - an awesome tube website, here is their link below >
A practical 7189 Case Study - Olson AM240
Many of these Olson amps were toasted and roasted by EL84/6BQ5's
A pity I did not take photos of the damage to the Output Transformers on the parts unit I bought for $50
before I discarded that chassis and roasted Transformers at the local dump
The OPT's were dark charcoal black inside, the Mains Transformer oozed of dark resin and had that burned aroma
Someone used EL84 in the AM240 BBQ, with obvious catastrophic consequences
This donor parts amp carcass gave me a nice AM240 Top Cover and also a real Bottom Plate.
So what tubes do 7189 amps need... the best, Russian 6n14n-EB Tubes, they are tough as nails
Below are some useful links to what I see as good 7189 resources
https://www.antiqueradios.com/forums/viewtopic.php?t=148527
https://www.dougstubes.com/nos-6n14n-eb.html
https://upscaleaudio.com/collections/power-tubes/products/russian-6h14-7189
http://www.mcshanedesign.net/tubes.htm
Manifestation of Tube Wisdom
Mr. Kevin Deal - SME (Subject Matter Expert)
"THE HIGH PRIEST OF TUBES"
Video direct from Upscale Audio
Note that when great solid advice is given, certain reactions may manifest
"You are not generally upsetting a person, you are upsetting their programming"
"Man Cave" #6 in Virginia, #7 Under Construction in Rochester NY
My Personal Guitar Collection (began mid 70's)
Giannini GNF-8R CEQ (Brazilian design, crafted in China) my January 2020 Ebay Score
Fender Newporter (made in Japan) plays and sings, installed 18:1 Grover Tuners, from Roanoke, VA, 1996, Pawn Shop
Giannini AWN-20 3/4 size (Made in Brazil) my oldest guitar from 1974, needs a bit of fretwork, loyal as loyal cand be
Epiphone Invader Electric (Made in Japan), plans to swap out cheap Machine Heads for Grover's, WIP.
Never fear... just rely on turn-key Hangover Service
in Las Vegas, Nevada
When you party in Las Vegas, and wake up feeling like HELL
Google the "Hangover Bus", they will fix you up... for a price
Master Percussionist
Mr. Billy Cobham
I met Billy in Panama City, Panama
Listen to "Palindrome" & "Glass Menagerie"
"One Word" from Mahavishnu Orchestra "Birds of Fire", amazing
Billy's virtuosity and skills, they transcend this existence
Billy's playing emanates from somewhere within a parallel universe
The Old and New Geek Testaments
Of thy Sacred Electrical Theory
Remember always safety first
Prevent fatal electric shocks
& Soldering Iron Burns
Always use Eye Protection
Never work when tired
Use good lighting and magnification
When measuring, one lead, always grounded
One hand with probe, other hand in pocket
No Alchohol when on the Bench
And don't spill the Coffee either
My General Bio and Tube Legacy
"From Sousaphone & French Horn to Guitars & Vacuum Tubes"
Born on Urantia (Earth), I am a 787,236 years old today
MY ASTROLOGICAL SIGN
First Xmas Concert, on Sousaphone - '72
Gianinni AWN-20 3/4 Student Guitar - '74
1st Sousaphone '73 to '80
Twice Arian Music Award Recipient '79 & '80
My Sousaphone mentor, My. Jay McCallister (RIP) awesome musician
Graduated as an Antilles Pirate - Class of '80
Played AHS Soccer #4 - 1976-1979
Tore my Meniscus, so much for Soccer..... after that
AHS Soccer Coached by the best Math Teacher ever - Mr. Paul Trittschuh
We had the honor of having a Girl play on our Boys Soccer Team
We were, ahead of our time....
Little did I realize that Maxwell was the father of "The Quaternians"
As I learned Maxwell's Equations as an EE and applied them
Just like E.L.P., in the beginning
To the left, my first Vacuum Tube Amplifier - late 1972 (Photo in 73-74)
The LP spinning - Elton John's Greatest Hits Vol.1
The age of Alice Cooper, The Who, Black Sabbath and Led Zeppelin
Tube Amp pulled out of Dictograph 100A Mono Console
a hand-me-down gift from Mr. Beck
Thank you so much Mr. Beck
You launched me on this journey
100A Console and internal Tube Amplifier
From Radio Museum Website (thank you!)
https://www.radiomuseum.org/r/dictograph_100_a.html
https://www.radiomuseum.org/r/dictograph_10w_amplifier_chassis.html
B.S.E.E. - Class of '86
Electrical Engineering
Month's out of College
Motorola Site Survey Work 1987
Radio Systems support, late 80's
Cool High Voltage "Hockey-Puck" EIMAC Tubes
Microwave Transmitters +1250 Volts DC on the Plates
The tube cage had an "interlock" plug, to avoid shocks
Legacy 1962 Lenkurt Microtel 76A Microwave Radio (2 GHz)
The MW system was as old as I was, yellowing Service Manuals
by turning pages they would rip apart
