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From €145.00 *

*Prices incl. VAT plus shipping costs

Currently out of stock. Expected to be available from: 21 January 2022

Type: Octal or Noval:

Quantity Adaptor:

  • BM2
  • 13x9.5x20.5 cm
  • 0.333 kg
  • 4251594901617
Measures BIAS current of the most power tubes in your amp. english/german operation... more
Product information "BIASMASTER System"
Measures BIAS current of the most power tubes in your amp.
english/german operation manual.    
The BiasMaster(TM) allows to monitor the bias current savely and easily. While adjusting the Bias control pot of your amp the BiasMaster(TM) does show the actual result. This lets you set and evaluate all reasonable biasing range your amp and tubes offers to find and set your personal perfect choice.
The Bias setting has a dramatic impact on the amps respsonse, break-up and dynamic character. 
Select octal adapters for the use with 6V6, 6L6, EL34, 6550, KT66, KT88, etc, or noval adapters for EL84 applications.
Read, write and discuss reviews... more
Customer evaluation for "BIASMASTER System"
2 Jul 2021

A MUST HAVE - Safe and incredibly useful

Been using it for years now.
This is a MUST HAVE for anybody who services tube amps.
Very useful and much safer for musicians that maintain their own equipment.
Avoid soldering resistors and measuring with dangerous traditional methods. Tube amps work with lethal voltage levels...

26 Mar 2021

Fabulous bit of kit

Very simple to use but very effective, literally just plug in, turn on and adjust bias if necessary. I use a wooden coffee stirrer from a local coffee shop to turn the bias pot in my EC Twinolux in case I accidentally touch anything serious. The bias of the amp was set way too high when I bought it used and caused red plating in a TAD 6L6 WGC as it goes, plugged the bias master in, replaced with a pair of NOS Jan Philips and set bias near to the top end of what they recommend for this amp and now it sounds fantastic and I have the price of mind that everything is as it should be.

2 May 2019

The TAD bias tester is dead easy to use and I was able to adjust the Fender Deluxe for clean tones very simply. You adjust, play through the amp, fine tune with your ears making sure you are operating at recommended settings. Pays for itself after 2 bias set ups.

8 Feb 2015

Super-duper handy tool !

15 Mar 2012

Excellent !

7 Dec 2008

Simple and easy to use.

I measured the bias current in my amp with the 'stock' tubes, so I know what it should be when I replace them. On my amp, I had to remove the chassis because there isn't enough space inside to fit the adapters.

Careful, some amps have the 'standby' switch wired in series with the power tube's cathodes, so there can be a few volts on the aluminum faceplate of the meter (_50V DC with my amp!) when the standby switch is off. If you don't know what this means, let your tech do the work on your amp.

24 May 2007

One of the most rewarding tools in my workshop, i couldn't live without it anymore!

Be carefull with the octal probes, they are a little fragile but if you use them in a normal way (without excessive force) they will last a long time!

13 Nov 2006

Quick and easy to use.

Accuracy checked against transformer shunt method with Fluke on and much safer to use!

Essential bit of kit for those who like playing with their output tubes. If you have a bias pot, it pays for itself after a handful of installations, compared to a tech's rebiasing fee.

5 Jan 2005

Works well but the connection to the Bases are in the way of the Valve retainers in the ENGL AMP........

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