Dang, sorry, I wish that had done it. I had a bit of back and forth to get my P20 just right, and now am quite happy with it. I hope you will end up in that same place.
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Ouch, I canât imagine what it must take to carry the P15 up there⌠I see why A/B isnât very practical. Thanks for the impressions regardless though.
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Hi Tony,
Itâs unfortunate about your issues and I feel for you.
I recently read an article about dc offset and how it affects amplifiers with large toroids. They even reference some PS Audio gear in the article. I thought Iâd forward this to you to read for interests sake:
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Two things about that, I tried that Emotiva unit thinking that DC was a problem even after getting the P20.
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The P20 is supposed to get rid of DC on the line so it should not cause the amps to hum more (unless there is an issue with it!)
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The emotiva thing hates (makes a massive noise) when you put it after the P20
Just wanted to let you know my experience to add to what @RsZk said.
I did use a multimeter and measure DC out of the wall in the end when @hthaller let me know that all it took was setting the meter to DC and putting the probes into the wall, turned out mine was fine, but worth checking!
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I use my Emotivas powered by a Power Plant and they are dead quiet.
Hey @Paul, @RsZk was referring to the cmx-2 which is a dc blocking power strip not one of the emotiva amps
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What I thought was interesting was trying to locate the DC offset by troubleshooting at the breaker panel side. Shutting off breakers until the hum would go away. This could go a long way for remedying the issue, before purchasing items such as the Emotiva cmx-2.
Edit: the OP also stated he had transformer hum even at the wall prior to the P20, but this was at a much lower level, so this is why I posted the article.
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Totally agree, especially if you have dedicated lines it does help eliminate things quickly
Thanks! I am a pretty fortunate guy if this is the biggest problem in my life right now, a lot of people have real problems to deal with. So although it is frustrating, you have to put things into perspective.
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Thank you! I didnât consider that, I will try the DMM when I get home tonight to see if there is any DC on the line.
The multimeter says I have 25mV of DC at the outlet if we can trust it. It would make sense though since the transformer was humming prior to the P20 (it just wasnât nearly as loud).
Is the P20 supposed to block DC? If not, would its function amplify the DC on the line through its conversion?
@Paul any Humbusters lying around you could send me to test?
My understanding is that the P20 is supposed to block the DC. Have you plugged a cord into the P20 output and done the same test with the multimeter to measure DC?
Sorry just added output, tested output of the P20
Good idea! The reading was the same out of the P20. Not really sure how accurate these measurements are though, not sure if its a bullshit number or not that I am getting out.
I will admit that when I was going through this I went a bit nuts and ended buying a Fluke Meter, which was more accurate than my crappy amazon special 10 dollar one. But my DC test was pretty accurate. You could always test a couple batteries
The P20 should block incoming DC. I donât have any Humbusters left. Wish we did!
You donât need a Humbuster if you have a P20. Besides, Humbusters can introduce other problems in your electrics.
Troubleshooting with PS Audio customer support wasnât going anywhere fast. To quote their response directly:
It sure as hell seemed like the P20 to me seeing as only after connecting my amps to it did they begin buzzing obnoxiously loud. So I decided to initiate my own troubleshooting methodology in purchasing an Emotiva CMX2 as @RsZk suggested. I connected my amps to the CMX2 and the CMX2 to the P20, the humming has completely disappeared. It appears that the P20 is adding its own DC offset to its AC output.
When I got home this evening my McIntosh C1100 pre-amp plugged into the P20 would not power on. I unplugged it and tried a wall outlet still no luck. It is awfully coincidental that all these things are happening to my gear since I got the P20.
The CMX2 is connected to the output of the P20, and the buzz went away, right?
It is connected to the output and yes the buzz went away:
AMPâ>CMX2â>P20â>Wall
And the CMX2 is a DC offset blocker. So all the symptoms are pointing at the P20 adding a DC offset to your AC. This is a brand new P20 that doesnât work properly out of the box? Sounds like you need an RMA and send it back.
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