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Hoffman Amps Forum image Author Topic: GK 600 Backline Losing Power  (Read 6731 times)

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Offline dpm309

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GK 600 Backline Losing Power
« on: August 12, 2022, 02:21:24 pm »
Have a GK 600 Backline that loses power after playing it for 30 to 45 minutes. Cooling fan seems to be working fine. Anything I should looking for when I open it up?

Offline shooter

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Re: GK 600 Backline Losing Power
« Reply #1 on: August 12, 2022, 03:28:30 pm »
things getting HOTTER than normal over time.
transistors n IC that "work" but are failing tend to breakdown faster from heat (on-time). old resistors the same.  Caps tend to drop voltage the longer there're on so maybe monitor voltages as you lose sound.  same with the other parts, the hotter they get the more current they draw building up the heat further.

Went Class C for efficiency

Offline dpm309

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Re: GK 600 Backline Losing Power
« Reply #2 on: August 12, 2022, 04:04:31 pm »
Thanks Shooter. I'll open it up to look for any signs of overheated components etc. I also read online that the overheating could be caused by running it at 2 OHMs. That would make sense if the speaker cabinet was 2 OHM which is not the case. I could see if you plugged in a 8 or 16 OHM cabinet into the 2 OHM jack.

 


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