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JCM 800 pre-volume puzzled

6/8/2004 8:10 AM
Greg	JCM 800 pre-volume puzzled Just completed a JCM 800 clone, sounds great, just one bug. With the gain set between 1 and 4, it seems normal, clean to bluesy tone. Gain between 4 and 7, sound is very weak, distorted and sound seems to die off abruptly (sounds like when you turn the amp off while your still playing, that weird highly distorted/buzzy dying out sound). Gain between 7 and 10 is normal again, loud with good pre-amp overdrive. Amp really sounds great except for this mid-range area on gain control. Note: You can actually hear this kinda dead area as I sweep the gain control full travel back and forth with no input signal. Thanks for any suggestions.

6/8/2004 8:10 AM

Greg

JCM 800 pre-volume puzzled

Just completed a JCM 800 clone, sounds great, just one bug.

With the gain set between 1 and 4, it seems normal, clean to bluesy tone.

Gain between 4 and 7, sound is very weak, distorted and sound seems to die off abruptly (sounds like when you turn the amp off while your still playing, that weird highly distorted/buzzy dying out sound).

Gain between 7 and 10 is normal again, loud with good pre-amp overdrive.

Amp really sounds great except for this mid-range area on gain control.

Note: You can actually hear this kinda dead area as I sweep the gain control full travel back and forth with no input signal.

Thanks for any suggestions.

Replies:

Bruce /Mission Amps If it's not just a bad pot, ultra h... -- 6/8/2004 8:27 AM
Greg Bruce,Thanks for the help. ... -- 6/8/2004 10:19 AM