Thanks in advance for any and all help. A friend of mine asked me to take a look at his JL 500/1 - I opened the case and immediately saw that some of the solder joints had at least been resoldered, the flux wasn't removed. Anyway, the power supply and the output transistors were all bad, along with a couple 47 ohm gate resistors. After replacing those the amp produces clean audio and doesn't make the popping sound when powering on or when the remote is used to turn it on/off, only when power is completely removed from B+ terminal - has anyone else seen this? I don't know if whoever looked at it before me moved the two trim pots, I'm hoping they didn't but have no way to know, are they somehow part of this? Thanks again for any advice,
Edit: Watching with a meter and a scope when the battery power is removed I see -21 volts across the speaker terminals for about 500 mS then it drops down to 0. Is this somehow half of the voltage on the speaker terminals being sent out through the speaker?
Edit: Watching with a meter and a scope when the battery power is removed I see -21 volts across the speaker terminals for about 500 mS then it drops down to 0. Is this somehow half of the voltage on the speaker terminals being sent out through the speaker?
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