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Guitar Amp Tubes Sets
  

TUBEMEISTER

TUBE INFORMATION SHEET

 

Tube Cross Reference Guide

 

Tubes may be known by several correct model names, each depending upon where it was made and how it was meant to be used.  The table of tubes below contains many of the common audio and radio frequency tubes used in vintage tube gear. 

 

Rectifiers/VR Tubes

U.S.A.

Industrial/Military

European/Russian

5AR4

 

GZ34, U54

5U4GB=5AS4

5931

GZ32, U51, U52, 5U4M

5V4

 

GZ32

5Y3

6087, 6853, 6004, 6106

GZ30, U50

6CA4

6100

EZ81, EZ91

6X4

6202, 5993, 6203

EZ90, E90Z, CV2844, U78

6X5

VT126, 5838

GZ31, EX35, U70, U147

12X4

 

HZ90

0A2

6626, 6073, VR75, 6830

150C2

0B2

6074, 6627, 6831

108C1

0C3

VR105

 

35W4

 

HY90

 

 

 

Preamp Tubes

6AT6

 

EBC90

6AU6

6136, 7543

EF94

6BA6

5749, 6660

EF93

6BE6

5750, 5915, 7036

EK90

6C4

6135, 6100

EC90, CV2842

6CG7=6FQ7

 

 

6CL6

6197, 6677

 

6CZ5

6973

 

6GW8

 

ECL86

6SC7

VT105

 

6SJ7

VT116, 5693

6J8 

6SK7

VT117, 6137

 

6SL7

VT-229, 5691, 6113

ECC35, 6H9C

6SN7

5692, 6042, 6180

ECC33, ECC32, 6H8C

12AT7

6201, 6789, 6679

ECC81, ECC801, E81CC, CV2016

12AU7

6189, 5814, 7730, 6680, 7716

ECC82, ECC802, E82CC, CV2011

12AX7

7025, 5751, 7729, 6681, 7058, 6057

ECC83, ECC803, E83CC, CV4004

12AY7

6072, 5763

 

12BH7

6913

 

12BY7/A=12BV7

7054, 7733

EL180

12DW7

7247

ECC832

 

6267

EF86, 6J32P

 

 

 

Power Amp Tubes

6AQ5

6005, 6095

EL90

6BQ5

7189, 7320

EL84, 6P14P/(6n14n)

6CA7

 

EL34, KT77

6K6

VT52, VT102

 

6L6GC

5881, 7581, 1622, 1614, VT115, 5932

EL37, KT66, 6P3S-E

6V6GT

VT-107, 7408, 5871, 7184, 5992

6N6C/6pi6C, EL33, EL32

 

6550

KT88

6146/6146A

8298

 

6146B

8298A, 6293

 

50C5

 

HL92

 

 

 

Tube Codes

Many tubes were manufactured for third parties and carry the third party “Brand” name on the, but were actually manufactured by a different company.  You can find “RCA” tubes made in a Sylvania factory and “GE” or “RCA” tubes manufactured in a Tung Sol plant.  Confusing? – Yes!

So how do you know which company actually manufactured the tube you are holding?  Most tubes have a Factory Code printd on them, and maybe an EIA (Electronic Industries Association) Code and these codes tell you the answer (many have rubbed off over the years so you have to be a good tube detective!)

Here are the most common factory codes found on many vintage tubes:

Code

Manufacturer

111

Amperex

158

Dumont

188

GE/Kenrad (188-4, 188-5, 188-20, etc)

210

CBS/Hytron

247

National Union

274

RCA

280

Raytheon

312

Sylvania (also triangle with “S”)

322

Tung-Sol (USA)

323

United Electronics

336

Western Electric

337

Westinghouse

1022

Fisher branded Mullard/Telefunken/Amperex

1109

Raythron (Japan)

U.S.A.3

Tung-SOL

Xf1,Xf2,Xf3,Xf4

Mullard

8I

Toshiba (Tokyo Shibaura Electric)

 

GE made many Admiral tubes.

Sylvania made many tubes with brands like: Fisher, Conn Organ, Magnavox, Crosley, Philco, Ford, Admiral, Motorola.  Also famous for their “Chrome Top” tubes.

CBS Hytron was a high quality manufacturer but much smaller than the main tube manufacturers RCA, Sylvania and GE.  They made tubes with the Motorola, Traveler, CBS-Hytron brands and many others.

The CBS Hytron construction is easy to identify: Clear Top design, Black Plates, the famous hole in the plastic key pin, getter shaped like a `square D`. Vintage is 1950s.

RCA was a large tube manufacturer and made tubes for brands like Magnavox, Emerson, and Motorola.

 

Tube Bias Settings

Tubes must be biased correctly to operate as designed.  Some amplifier are self biasing in that they use a fixed bias or a cathode bias which is not adjustable.  With these type of amps (like many 6BQ5/EL84 and 6V6 based amp), you may just replace the old tubes with new ones and forget about any bias changes.

 

Other amps have an adjustable bias potentiometer for fine tuning the bias settings.  If you don’t have a bias measurement tool for setting the correct bias, leave the bias setting alone and just substitute the new tubes.  If they begin to glow a cherry red, the bias is set incorrectly and will have to be adjusted (down or more negative) to get rid of the cherry glow on the plates.  Usually a mid range setting will suffice, but if you do have a bias setting meter AND you know how to SAFELY set the bias then the setting s in the following table may be helpful if you do not have access to your amp manufacturer’s specifications.  If you do not feel comfortable making this settings, by all means take the amp to a qualified amp tech.

 

Tube

Bias Range (mA)

6V6

22 – 27

EL84/6BQ5/7189/6P14P

22 – 27

6L6, 5881, KT66, etc

30 – 35

EL34/6CA7/KT77

35 – 40

6550, KT88

40 – 50

 

For a great selection of audio tube sets for popular guitar amps and radio frequency tube sets for popular radio transmitters please visit my eBay store at:

 

Der Tube Meister

 

Updated July 16, 2012

 

Copyright 2012 Tubemeister