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PS Audio P300/Rogue 66 preamp wierdness

I recently purchased a new Rogue 66pre. Now, in case your not familiar,it is a inverting polairty tube pre-amp with 2-12AU7 tubes and a seprate power supply. It only seems to operate well with the P300 in the PS2 multi-wave setting (not bad in SS5, SS6 and SF7). Normal sine wave at 60 hz is not to bad but as you increase the sine wave setting past 60 hz I start to hear a humming sound which increases with intensity as I approach 105 to 120 hz settings where its unbareable.

Now, at other multiwave settings such as SS1,SS3, SF4, SS8 and SS9 I hear a wierd thumpimg, humping sound (pardon my electronic dumbness). Therefore, cetainly can;t play it in these modes.

Does anyone know what the deal is here ? Anyone else have a Rogue 66 and P300 and encounter the same thing ? No problem when I have the preamp plugged into wall and only CD plugged into P300. I only plug the pre and cd into the P300.
Any insight would be greatly appreciated.

Assoicated equipment: Bryston 3B ST amp, Arcam 8 SE CD
Mirage OM6, MIT T2 biwire speaker cab
Bryston and WW EQ 111 interconnects

thanks,
Paul
nb_dude

Showing 1 response by kenl

kenl
131 posts
 
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
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