Just acquired a mint 700M but it has dirty level control pots. Does not look like there is a spot to get the deoxit in there. Anybody had to do this ?
Kenwood 700M- how to clean level control pots?
- Thread starter VintagePlus
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They are sealed, and it's unusual to see a noisy one. The few times I've seen one that had noise issues, a workout by running the control through its range a few times seemed to clear it up.
Still, you don't really control the volume regularly with the pots on the amp...set 'em where you want 'em (usually wide open) and forget 'em.
Still, you don't really control the volume regularly with the pots on the amp...set 'em where you want 'em (usually wide open) and forget 'em.
Thanks for chiming in Glen. Right channel is quite a bit louder than the left when I run my iphone straight into the amp. Adjusting the right side level is as it should be but the left is more than 50% quieter. Any ideas? Unit is like new and never been worked on as far as I know. I'll be recapping in the future but would just like to get this issue fixed first.
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Glen,
I've isolated the problem to the power amp now. Or are you referring to the sub sonic filter?
I've isolated the problem to the power amp now. Or are you referring to the sub sonic filter?
Well, I didn't walk over to my 700M to see exactly what it's called, but yes, the subsonic filter switch interrupts the signal path and is a potential spot to lose the signal.
The gain of the power amp itself is fixed (as nearly all power amps are), so as long as the amp is operating, I'd expect that any signal that makes it to the first amplification stage will get the same amplification as the other channel. It's an important concept to keep in mind when troubleshooting power amplifiers, in that the things that can go wrong that would cause one channel to have lower gain than the other are not impossible, but unlikely. Therefore, 99 times out of 100, any signal attenuation that occurs happens before the signal makes it to the driver board.
The gain of the power amp itself is fixed (as nearly all power amps are), so as long as the amp is operating, I'd expect that any signal that makes it to the first amplification stage will get the same amplification as the other channel. It's an important concept to keep in mind when troubleshooting power amplifiers, in that the things that can go wrong that would cause one channel to have lower gain than the other are not impossible, but unlikely. Therefore, 99 times out of 100, any signal attenuation that occurs happens before the signal makes it to the driver board.
Glen
Thanks very much. I'll clean that switch really well and post back this evening.
Thanks very much. I'll clean that switch really well and post back this evening.
Have narrowed the issue down to cold solder joints on the protect board. Desoldered and re-soldered many points including all connector pin locations and am near completion. Nice sound through both channels.
