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Parasound JC-1 - Standby during playback?

Recently I installed a 20A DB for my dedicated room with 2 outlets - One outlet goes into a Shunyata Cylcop serving the Parasound JC-1 and the other into another Cyclop for the front electonics.

I noticed that there are occasions when BOTH the Parasound amps will go into standby mode (RED light) for about 1-2 secs before powering on again (BLUE light). During this time, the front end electronics are still functioning.

Since both amps are experiencing the same thing, then it means that this may have something to do with the electricity? Else a problem with the preamp? Again, I must say this does not happen very often but a nice solution will be great indeed!

Thanks for the advice.
shsohis
sfstereo
215 posts
 
It's possible that when both amps are turned on the same time, the line voltage may drop due to high inrush current and cause the amps to go into standby. You can try turning on one amp at a time see if the problem goes away.
bpwalsh
1,197 posts
 
Shsohis, if you're turning on the JC 1s via the 12V trigger rather than manually, it's certainly possible a bit of DC could be coming from the Nagra preamp. The amps should be turned on last and turned off first, and when turning on allow time for the preamp to stabilize before turning on the amps. The turntable power supply should be turned on before or at about the same time as the preamp.

Please let us know how this works out for you.
shsohis OP
119 posts
 
I bought a pair of walwart 12V power supplies for he JC-1. I have set them power up in such a way that one lags the other by about 12 secs.

Meanwhile, I have started with the recommended powering-on sequence - so far so good. I need to monitor for a longer period of time. Pray this works. Will come back with an update - positive one I hope! Thanks all!
dhl93449
455 posts
 
You can set the JC1s up so that they have a staggered turn on cycle. You do this by adjusting the turn on delay control at the back of the amp. Even if they get simultaneous 12 V turn on signals, they will power up after different delays. You should not need staggered 12 V turn on signals. I do this with my JC2 powering up both my JC1s. Same 12V siganl from the preamp, but I have the delay set differently on each JC1.

I am not sure what using the 12V turn on signal would have to do with DC coming from the pre-amp. They are completely different issues. DC on the audio input to the amp triggers a fault condition which puts the amp in a protection mode. Unless the implication is that the JC1s are powering up before the DC levels on the preamp settle to zero. In that case use the longer delay settings on the JC1.
bpwalsh
1,197 posts
 
Dhl, have you experienced the phenomenon described by Shsohis? I do not use the 12V trigger feature but have seen such behavior due to upstream components which in fact may put one or both amps into protection mode briefly. Your suggestion of adjusting the turn-on delay is a good one.
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