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10" (25.4cm) wide, 5" (12.7cm) deep, 3-1/2" (8.89cm) high.
Instructions for Use
I received the 100 Watt Attenuator you built. Great workmanship (thought it was a thing of the past) and it works flawlessly. I can turn the vibroverb to 7 and get great tone without my ears bleeding and the other features on it give me a wealth of options in creating the tone I want.
Once again, thanks for taking the time and pride in your work to do it right!
25, 50 and 100 watt MASS. 2, 4, 8, 16 ohms, 0, 3db, and 6db treble boost, MASS bypass, line out, tone stack for line out, tone stack bypass, extra output jack, range switch. All controls are on the front panel. The MASS employs an actual speaker motor for the load to yield a realistic interaction between the attenuator and the output circuit of the amp. The attenuation is continuously adjustable from zero to over -70db using the speaker control and the range switch. By turning the speaker control to minimum (maximum attenuation), the unit may be used as a dummy load for testing or for DI use. Optional wings ($25) may be employed for rackmounting the MASS. The MASS occupies two rack spaces and requires adequate ventilation for proper operation.
Please read and consider the following prior to ordering an attenuator:
Here are some facts to consider when using an attenuator. Attenuators do work. They are not the cause of transformer failures. An attenuator can only simulate two out of the four components that are involved when you crank up an amp. The four components are #1 preamp tube distortion, #2 power tube distortion, #3 speaker distortion and #4 the physical movement of air that your speakers produce at high volumes. So the two components missing are speaker distortion and the physical movement of air and these are huge components! So if you’re playing at moderate volumes and just want to tame the amp down to get a bit of power tube breakup then an attenuator is a great tool, but do not expect to be able to dime your amp and then use any attenuator on the market to get the exact same sound from your amp at whisper quiet volumes. You can't get there from here. You would be better off with a one watt amp.