Bias Master™ - TAD, tube tester, with 4 probes
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
Accessory Items:
| Probe Type | Our Part Number | UPC/EAN |
|---|---|---|
| Octal | S-TBM4 | 841358106163 |
| Noval | S-TBM4-EL84 | 841358106170 |
| Item Height | 2.1 in. | |
| Item Length | 5.76 in. | |
| Item Width | 3.6 in. |
| Packaging Dimensions | 8 in. × 5 in. × 3.75 in. | |
| Weight (Packaging) | 1.048 lbs. |
| S-TBM4 - Octal version | Item Height | 2.1 in. |
| Item Length | 5.76 in. | |
| Item Width | 3.6 in. | |
| S-TBM4-EL84 - Noval version | Item Height | 2.1 in. |
| Item Length | 5.76 in. | |
| Item Width | 3.6 in. |
 Operation Manual | All Models |
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Questions and Answers
Click each question to see its answers.
1 answers
Can you bias an amp with a multimeter?
Asked by Anonymous on November 3rd, 2017.
November 8th, 2017
Staff Member
Yes you can but the bias meter simplifies the process and does the mathematical conversions for you.
1 answers
Does it come with a list of different amps to get bias numbers from ?
Asked by Anonymous on January 16th, 2019.
January 16th, 2019
Staff Member
No, such a list is not included with this meter, but we have provided a bias calculator that may be of assistance: https://www.tubesandmore.com/tech-corner/tube-amplifier-bias-calculator
Product Reviews
Finally got myself one of these, after wanting one for quite some time. I can now easily check and set the bias on my amps, and the TAD Bias Master makes it very enjoyable. Thanks to TAD and AES.