• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

GM-70 All done

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deafbykhorns

deafbykhorns

Member
Joined 2004
MelB said:
Finally got my GM70 amp all done. Sounds just great! Could not be happier with how it turned out. Sounds even better than my Parallel 300B amp. Very good base control. It is driving into a JBL E140 in a 200 pound box tuned at 30 Hz.

The Hammond 167P18 (18v 5 amp) works perfectly for the filament supply. So perfect in fact it's 77% efficient with a linear regulator.
Click to expand...

Where did you source that ammeter? It's a nice vintage look
 
M

MelB

Member
Joined 2005
deafbykhorns said:
Where did you source that ammeter? It's a nice vintage look
Click to expand...

The ammeter is a Simpson 05690. Mouser can get them for you. Wow they are quite expensive now. Think they were ~$75.00 CND when I got them.

Also latest schematic here.
 

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