Marshall DSL - TSL100 and TSL122 Standard Retube

PLEASE READ THE TEXT BELOW THAT EXPLAINS THAT YOU DO NOT NEED TO USE A BIAS PROBE!!!!!

This video is of a Marshall DSL100 and the bias procedure is the same on TSL100's and 122's. For the DSL50 the procedure is the same but you would be setting the bias between 40 to 45 millivolts. The middle prong is your ground. The test points or prongs are shown in the video and in the pic's below.

The most asked question we get is "do I need bias probes that are like the ones shown in this video to bias my amp." The answer is no. If you listen to the video I will explain that I'm showing two different methods of reading bias and showing the probes and meters so you can get a better visual  on how the bias works. All you need to bias one of these amps is a simple multimeter to do the job.

The second most asked question is "what setting do I use on my multimeter" The answer we give in the video is Millivolts!

The third most asked question is "do I use the black or negative lead for the middle test prong?" The answer is yes!

The fourth most asked question is "do I bias the amp in standby?" The answer is no! The amp must be in the play mode to adjust the bias.

The fifth most asked question is "do I have to have a speaker plugged in?" The answer is YES! You MUST have a speaker load on the amp.

The sixth most asked question is "what do I bias KT77's at?" The answer is EL34's, E34L's, KT77's and the big bottle JJ 6CA7's all bias up to between 40 to 45mV in 50 watters and between 80 to 90mV in 100 watt DSL's, TSL's and JVM's