PS Audio S300 turn on/off question?

Just received my new S300. Can’t believe how quickly Caleb got it here. Big thank you for that.
This is my first post here.

So S300 turn on is kinda tricky/picky. I understand that the amp back switch needs to be off before hooking/unhooking components or plugging into AC wall socket. Otherwise bad things can happen to the amp. The manual says to leave back power button on and use front switch for standby. Question is, what happens if there is black out and the power comes back on? Wouldn’t that technically be the same as having rear power switch on before plugging into the AC receptacle? Don’t want to fry the amp.


Welcome to the forum! Yes, you’re correct, which is why many of us unplug during thunderstorms and the like. The power simply being off then on shouldn’t bother anything, it’s a surge in a storm that you’d be careful of.
The reason for keeping the main power on is to keep some parts thermally stable I believe, so that when you power on from the panel you’re ready to go.
I’m sure if I’m wrong about this someone will say so.

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Welcome to the forum, and michael_lichnovsky offers some fine advise. It comes down to a matter of balancing intended near term use with the risk associated with a power interruption or storm incident. Isolating one’s system in anticipation of a severe lightning storm is wise, when possible. Also note, your local utility’s power restoration efforts can also wreck havoc on sensitive electronics.

I have M700. I live in Texas where thunderstorms are typical during the summer season. I always have my gears main power off also due to I only have time to enjoy serious listening during the weekend. (Of course, I unplug everything when needed.)
The “stand by” in PSA gears are “output disabled mode” to keep the gears in warm up condition for best sounding. It still consumes more electricity than the “stand by” mode from my TV for example. In my situation, I usually main power on my gears early, give them, say, one hour to fully warm up before a good listening starts.
My M700s took months to get fully break-in. The sound became very nice after that. I think S300 will do the same too. Enjoy my M700, I bet you will enjoy your S300 too.

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Thanks everyone. Living in Missouri, I have lots of experience with storms. I always unplug during lightning storms and bad weather. Weather forecasts are watched for signs of trouble.

The system has a dedicated ac line with all components plugged into diy distribution block. If I’m away when weather gets unexpectedly bad, family members will pull the main plug out of the wall. The DAC always stays on and isn’t affected by this. Not sure if the S300 in output disabled mode would be or not?

The other worry is if power goes off, then comes back on without any surge, while S300 is in output disabled mode. If only a surge causes a problem I can risk using output disabled mode. If normal power interruption without going thru boot up causes a problem, I’ll just leave amp off.

Breaking the S300 in now. At about 20 hours. Room is a lot cooler. Amazing how much heat class A transistor amps and tube amps with 8 6550 tubes generate. :slightly_smiling_face:
The DAC and definitely the tube linestage get hotter than the S300.