PS Audio P300/Rogue 66 preamp wierdness

The power supply in your amp is designed for 115 VAC 60 HZ input. The filter caps in the power are designed to filter ripple at 120 HZ if your amp has a full wave rectifier. If you increase the input frequency to 120 HZ, the ripple is at 240 HZ and the filter capacitors are not being given the opportunity to charge enough, therefore not filtering the ripple and becomming audible.

Paul,

I believe the noise you are hearing has to do with mechanical transformer hum. There have been several posts on this subject. Certain components suffer from this when used with the PS 300. According to Paul McGowen @ PS Audio, while annoying, it causes no harm.

But there is another subject you need to be aware of. Paul told me that depending on the multiwave setting you're using, you need to adjust the voltage setting on the PS 300. Below is his response to my question on whether the multiwave settings are harmful to tubes. . .

"No problem with MultiWave as long as you make sure the voltage is the same.

Higher frequencies don't bother tubes at all.

Sin. 117.0v
SS1 118.2v
PS2 126.9v
SS3 118.7V
SF4 116.3V
SS5 126.1V
SS6 126.6V
SF7 116.7V
SF8 116.3V
SF9 116.7V

Use this chart to determine the voltage setting you need. SS1, for instance,
needs no adjustment. PS2, needs a 9 volt drop in voltage".

Upon receiving this info, I was a bit confused, so I went back to Paul for a clarification. Here's his response. . .

"No, I think I was not clear. SS5 is 126. That’s what comes out of the Power Plant when you go there with no modification.

The goal for you will be to achieve 117 on all voltages.

So, when you go to SS5, DROP the voltage so it reads 9 volts lower (108). When the front panel meter reads 108 volts, it is really 117".

Paul, I hope this helps you. If you're still concerned or confused, I suggest you visit the AudioAsylum site, and go to the PS Audio forum. There you can send a query directly to Paul McGowen, head man of PS Audio.

Regards,

Ken

The Rogue 66 is a solid, musical preamp. My suggestion is to use the most basic settings, i.e. a solid 60Hz sine wave, with the least waveform compensation possible. That loud hum is telling you something is not right.