Conrad Johnson Owners.com

Head low, I tell this tale.
Premier 350 amp plugged into a Furman IT Ref power bank. I had my 16LS2 plugged into same bank. Revel Performa3 F208's bi-wired to 350. I had swapped out my Premier 17LS because I had been wondering if it sounded better than my 16LS2 and plus wanted to swap the P16's tubes, so why not. I put the Premier 17 on a different outlet, a Panamax M5400 which housed my cable TV wireless, switch, etc and because it was easier routing that to the Panamax. The P17 sounded great. Later in the day, the cable box was giving trouble. I had to swap out some wires and one thing to another. The amp was on, the music was playing. In a moment I'd forgotten I put the Premier 17 on the Panamax along with the cable stuff. In a quick moment I had all the cable stuff off and at last minute decide to move the Panamax to a new outlet just below to make room on top of the 2 gang 110 outlet. My helper pulled the plug, the Premier 17 went hard OFF. A loud pop through the Premier 350 to the Revel speakers. In a panic the plug went back in; a split second and the second thunderous pop.

The right speaker of the Revel is toast; the crackling of the 8" speaker. Now what to check.
I'm more worried of the Premier 350; want to know what you think I need to check, all visible fuses are accounted for and ok. There are 8 fuses in the Premier 350 power amplifiers. One is the ac power line (mains) fuse. It is located in a fuse holder on the back
of the amplifier, near the IEC main power cord receptacle. There are four fuses for the main DC power supplies. These are located on the
back of the chassis in fuse holders above and to the right of the power cord, labeled B+ and B-. On the bottom of the main pc board, there are
two fuses to protect the high-voltage power supplies. Finally, inside the amplifier on the right side near the ac power receptacle, there is a fuse
to protect the turn-on circuit. All fuses are accounted for but did not see the Turn on circuit. It turns on fine.
What volt reading should I look for from speaker out R/L? Ideas and thoughts.

Hola. What happened was that somehow while the amp was on, and turning some other equipment, a heavy transient was generated. An AC cable could does that. This cost to fried the cone speaker. Remember to follow the guide of turning on and off the entire system. The last turning on device, after 30 seconds, is the power amp. The first thing to turn off its the amp, and wait 30 seconds to have all the power supply capacitors discharged, then turn off the rest of the system. This way, if a transient is generated, it will not reach to the speakers.
Happy listening!

Sorry to hear about this event jahatl513. I agree with roberto, that is probably what happened when it was unplugged and replugged. I think this is one of those hard lessons we all eventually learn about having everything off when we are working on (or near) our systems. Hopefully, it won't be too expensive to replace the cone that was blown on the speaker.

As for the Premier 350, if the fuses are not blown and there is no apparent damage on the circuit board I would probably disconnect it from all other devices and plug it in. Look for any smoke or any other apparent signs of damage. Then I would power it all down and connect a really cheap source and a pair of really cheap speakers. Turn everything on as roberto suggested and see if it plays ok. If so, you are good to go.

Thanks guys, much appreciated. I wonder if there is a Schematic and advice using a MM to test output per channel once source is connected or...?

The DC at the output terminals should be less than +-30mV. Less than +-10mV is typical. Ideal is +_ 0 mV. I do believe that each channel has a balance DC control variable resistor where you can adjust for minimum +- DC balance.

My advice is, contact Conrad Johnson for their guide to do this. It's better to follow their instructions. Also, the Bias adjustment is a must. Be careful while doing this. You can burn the output stage if you don't do it right. Being your Premiere 350 a big monster, this is not an easy task. You should get an 8 ohms 100 Watts dummy load resistor. It will charge the amp as a speaker, and will not burn it if something goes wrong. If I were you, I will better use at least 10A variable AC line transformer to do the job. Also, an ampere meter will help you to see if the consumption is too much.

Good luck and happy listening!