Bias adjustment on solid state amplifiers

Just get a Digital Voltmeter with a current scale. Most have a scale with a range of milli-amps and also up to 2 amps and work fine for that.

thermal drift is real and significant, hence ON semiconductor thermal trac devices. Ayre used those in the VX-R and Mx-R.

for IMO a beautiful approach is the liquid cooled Vandersteen M7 amp....rock solid bias and a bunch of other innovations.

Get a Fluke DMM, a lifetime tool the kids will inherit 

@richfrankOften tube amp bias is measured across a resistor scaled to convert mV to mA.

500mA is a pretty hefty tube bias. 50-70mA is more like it.

What kind of amp?

There is no mention in most solid state owner's manuals for bias adjustment, because they are a design criteria and it is fixed.  The only time bias should need adjustment in solid state amps is when work was done on the amp and components were replaced. 

The bias, pre-driver and output drivers are typically located one the same heatsinks so that they may track with each other changes in heat.  hfe and other characteristics change with temperature.  This is why they are mounted on the same heat sinks.

Typical owners have no business adjusting bias on solid state amps.  

Also, many companies won't even tell you what the bias voltages (typically across emitter resistors) are in the first place.  Try getting that information from Mark Levinson company.  

If you upgrade the transistors to much better more linear transistors from older transistors, then yes, you need to know what the bias voltage should be.  If you add say, Threshold style heat sinks and want your class a/b amp to operate more in class A, then yes, you need to adjust bias.  upgrading the power supply and transistors are typically also required in this case.

enjoy