BIASMASTER System

From €169.00 *

In Stock, delivery time approx.1-4 working days (Within Germany)
The delivery times for shipping abroad can be found here.

Part Number: BM2
Packaging Size: 13x9.5x20.5 cm
Packaging Weight: 0.333 kg
UPC: 4251594901617

Measures BIAS current of the most power tubes in your amp. english/german operation... more

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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, KT77, KT88, KT120, KT150, KT170 etc, or noval adapters for EL84 applications.

Documents...

Available downloads:

Safety information...

Responsible person for the EU

Economic operator established in the EU, who ensures that the product complies with the required regulations:

Tube Amp Doctor Musikhandels GmbH

Weinbrennerstr. 1

67551 Worms

shop@tubeampdoctor.com

www.tubeampdoctor.com

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Customer evaluation for "BIASMASTER System"

From: Francisco On: 21 Jan 2025

A must have for tube amp owners

Unlike other probes this one is safe for your amp since it measures voltage drop through 1 ohm resistor, instead of breaking the circuit to measure current which can cause problems.

My BIAS Master has paid itself: I realised one amp was running at more than 100% dissipation. Other amp was too cool and now I'm able to replace tubes and set them correctly. Beware setting the bias is still dangerous if you are not careful and have adequate training for working with high-voltage.

From: Jakov Parat On: 8 Dec 2024

Bias probes can damage your amp

I had issues with biasprobes from 3 different units not wotking properly even causing damage by overheating the tubes with Soldano and vintage Marshalls amps.

From: Admin On: 9 Dec 2024

The BiasMaster probes are measuring devices but do not control current or bias. If bias isn't set or tubes are defective then overheating might happen, but not due to a measuring probe.
Please feel free to contact our tech support for any question you might have in this context.

From: Pablo On: 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...

From: Mathew Keith Davies On: 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.

From: Mike On: 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.

From: Peter De Coninck On: 8 Feb 2015

Super-duper handy tool !

From: Sebic On: 15 Mar 2012

Excellent !

From: Robert Platt On: 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.

From: didier joris On: 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!

From: Mark Burness On: 13 Nov 2006

Quick and easy to use.

Accuracy checked against transformer shunt method with Fluke multimeter...spot 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.