Bias Master™ - TAD, tube tester, with 4 probes

Tube Amp Doctor (TAD)
Pictured: Octal
Pictured: Octal
Pictured: Noval
Pictured: Noval
Click to zoom in
Pictured: OctalPictured: Noval
Customer Images:
No Images yet! Submit a product image below!

Bias Master™ - TAD, tube tester, with 4 probes

$228.95
In Stock
Free Shipping within continental U.S.

Bias Master™ system BM4 Measures Bias current of the vacuum tubes in your amp. Includes 4 probes and english/german operation manual.

The Bias Master™ allows you to monitor the bias current safely and easily. While adjusting the Bias control pot of your amp, the Bias Master™ shows the actual result. This lets you set and evaluate the full reasonable biasing range your amp and tubes offer to find and set your personal perfect choice.

The Bias setting has a dramatic impact on the amp's response, break-up and dynamic character.

Probe Type Measures
Octal 6L6GC, 6550, EL34, 6V6GT, 5881, KT66, KT88, KT90, KT100, KT120, 7027A
Noval EL84 types

For additional probes (for testing other types of tubes), see S-TBMA2-X

SKU:
S-TBM4-X
Item ID:
039836
Brand:
Tube Amp Doctor (TAD)
Part Numbers
Probe TypeOur Part NumberUPC/EAN
OctalS-TBM4841358106163
NovalS-TBM4-EL84841358106170
Item Height2.1 in.
Item Length5.76 in.
Item Width3.6 in.
Packaging Information
Packaging Dimensions8 in. × 5 in. × 3.75 in.
Weight (Packaging)Noval versionS-TBM4-EL840.9105 lbs.
Octal versionS-TBM41.0428 lbs.
S-TBM4 - Octal versionItem Height2.1 in.
Item Length5.76 in.
Item Width3.6 in.
S-TBM4-EL84 - Noval versionItem Height2.1 in.
Item Length5.76 in.
Item Width3.6 in.
PDF: Operation ManualAll Models

My Project Lists

You must be logged in to add items to a project list.

Specifications, Files, and Documents

PDF: Operation Manual Operation Manual67.08 KB
Questions? Contact us at [email protected], or give us a call at 480-296-0890

Product Reviews

2.00 out of 5 based on 1 reviews
John Head - April 12th, 2021
2 out of 5

One of the Novel biased probes had a continuity issue, I called and they provided me a return label for exchange. I was not willing to wait for the return process and new one to arrive. I took it apart and did the repair myself using a solder iron, they failed to pre inspect before shipment