Halo A21 Light Show

[MichiganMike]

I noted when turning on my Halo A21 after sitting idle for several hours there was a flash of light inside the unit near the left rear. It looked like it may be a spark. A few seconds later the relays closed normally and the amp sounds fine. I have sent a note to Parasound's service, but also would welcome guidance from the learned members of this forum as to the cause and cure.

This unit was purchased used, so there is no warranty.

Thanks,
Mike

[Chris D]

Uhhhhhh... can't be good. Obvious questions are, where was the unit sitting, was it by water, dust, dirt, etc, what is it plugged into, what did you hear from the amp when you saw this flash of light, do you see anything in/on the case in the area you saw the light from, and maybe is your AC power cord loose in the amp's socket?

[MichiganMike]

Chris,

I removed the top of the A21 to get a better look. The circuit boards and components were very clean. No sign of dust or exposure to water. No apparent burn marks that might occur with arcing. The AC power cord is firmly seated.

I turned the A21 on several times. Only once more was there a flash of light, but it was difficult to see the location due to components obscuring the area. I thought the flash might have originated from the area near what I believe is a relay. The flash occurs immediately with power on, not when the relays close for audio. I did not hear a noise with the light, but was several feet away.

One possible solution is to leave the A21 on. Currently, it is triggered by my Rotel 1068 and in turn triggers my A51. I will continue to monitor the situation and may leave the A21 on if this problem persists.

One additional observation, the A21 and A51 amps replaced a Rotel 993 and two Rotel 981 amps. Component layout and appearance to the untrained eye is neater and more impressive in the Parasound amps. At approximately twice the price per channel this might be expected.

Mike

[Peter Nielsen]

Mike, you might want to try to reseat the transformer and power connections. Those wires are not soldered in place, the connectors are regular disconnects. If one of those are not properly seated, you might very well see sparks...

Peter

[MichiganMike]

Peter, thanks for the helpful suggestion. You must be prescient or an expert on all things Parasound.

I moved some wires in a harness so I could view more clearly the area near the sparks. The sparks seemed to originate near a white plug. I unplugged the A21 amp, waited a while to make sure the capacitors had time to discharge and tried to seat the plug more securely. Since then I have turned the amp on twice and no sparks were apparent. Hope this solves the problem. I will continue to monitor it.

Thanks again for the sage advice.

Mike