Perreaux PMF 1150B Shut down anomaly

[AudioWill]

Evening,

I’m wondering if someone might have an idea of what might be going on here. I know there won’t likely be a definitive answer but maybe a few educated guesses.



I brought home a PMF 1150B power amp yesterday. Got to listen to it before purchasing and didn’t hear anything at the time. That said I wasn’t the one who tuned it off after listening to it. This morning I set it up and got it running and listened to it all day (office set up) with no issues. Sounded great, hit all the right chords, I was happy. When shutting down with separates, for the power amp I always follow the last on, first off mantra. I pushed the power switch off and it shuts off, but a low level static sound starts coming through the speakers. I shut off the preamp and it continues. Then I shut off the power strip and it continues for another 20 seconds or so and then fades out.



Thats not something I’ve heard before with any other amplifier I’ve had. Any thoughts on what might be causing it or what to look at?





Thanks,

AW

 

[avionic]

I pushed the power switch off and it shuts off, but a low level static sound starts coming through the speakers.

Sounds like there is no protect circuit relay and you're listening to the amplifiers main caps slowly discharging.

 

[avionic]

Thats not something I’ve heard before with any other amplifier I’ve had.

I'm thinking this perreaux model has no protect circuit relay. I'm thinking it has speaker fuses for some reason. I could be wrong. Been a real long time since I've been inside a perreaux power amplifier. There are a few makes /models of amplifiers out there without protect relays.

 

[Adda]

It has no protection circuit, my E2 also makes noises when discharging.

 

[stereofanboy]

I've noticed similar recently with an Aragon and a Crown that I don't usually have hooked up. With those, however, the sound immediately stops if I turn off the preamp, while his carries on.

Mine isn't low level static at first either. The music at first continues normally and eventually degrades into low level static before stopping altogether.

 

[RVT1K]

I've noticed similar recently with an Aragon and a Crown that I don't usually have hooked up. With those, however, the sound immediately stops if I turn off the preamp, while his carries on.

Mine isn't low level static at first either. The music at first continues normally and eventually degrades into low level static before stopping altogether.

That's what my Adcoms do. I increased the size of the main filter caps and the music can play normally -at low volume- for a while after killing the power.

 

[AudioWill]

Thank you for the replies.

An additional note, when I hit the power switch this morning I got the low level static for about a second or two and then it faded to dead silent. Music has been playing for about an hour now with no issues…sounds great! Interesting…


AW

 

[Adda]

My E2 makes a firm thump when powered on, so I expect your PMF 1150B would have some "personality" as well