P10 with THD In 1.2 and THD Out 2.1


This seems to be a bit unusual when the P10 doubles the THD. Looking at the scope screen I can se an ugly spike in the outgoing voltage and unfortunately when I started my equiment this afternoon both my Lyngdorf TDAI-2200 and Audionet SAM amplifier went black. Hopefully it is only the fuses that are blown.

Looking at the performance graph the increase of THD seems to have occured this morning when the P10 was in stand-by. What could have caused this? I installed the new multi-wave update a couple of months ago but this seems more like a hardware failure since the outgoing voltagelevels seems to go crazy.

Attached files


Even though I can’t call the voltages stable(neither in coming or outgoing), non of them would cause me concern as to whether or not they were dangerous to your equipment. A real spike in voltage is just that, and would be more in the order of 30 volts or more. This does not exempt the shown behavior as being ok, since it provides some kind of clue as to what was MAKING it behave this way. Wheteher an outside cause or one in the P10 itself, I cannot say.

The wattage being at only 120-130 at 4-5 PM assures that so far so good. No overdriving.

Then I see the THD which is pretty low at incoming, but is not being dealt with in a usual way by the P10, and this is the clue that points to the P10 itself. No doubt in my mind, something failed within the P10, but that’s all I can say. The graphs were very helpful.


I suspect a hardware failure of some kind, a big bother.


Yes, I suspect a hardware failure. Here comes some more pictures of the display. When I start the P10 the THD is about 0.9%, then after a couple of minutes I hear a click from a relay and the THD rises to 2.1%. The Voltage out is also too high since the setup is on 230V and it is regulated for low distortion.

Before I knew what was going on the main fuses in my 3 amplifiers had blown. Two of them are up and running now again after I have changed the fuses but I wouldn’t dare to connect anything to my P10 right now except for maybe a lightbulb.

Attached files


ouch that does not look right - output voltage should be nice sinusoid, you have 3 nasty spikes and flater top there :frowning:

I’d yet try to reload firmware and let the power plant unplugged from wall for at least few minutes to see if it helps…


Have you tried the wave shift below the multi wave setting. Just curious.



I have tried the different multi wave shift but there is no difference. I tried to install the old firmware 0.00.32 but still the high output voltage and THD.



Wow aside from something being wring inside I have no idea. I hope you find out . Did you try it with other outlets in your home or even someone eels too. At that point it must be defective .



I would not trust the readings until the problem is fixed. Also I think you should try to measure input / output levels with a voltmeter, and compare it to the readings.

Then contact PS Audio directly on this, once you have all the above info. Your P10 may have to go home, I think - but PSA will sort you out.


As an early adopter of the P10 and an enthusiast about watchign the settings, I can say I have NEVER seen THD out worse than in, or those terrible ripples on the wave diagrams. I wouldn’t trust a lightbulb! Time for it to go back to the mother ship.


I tried different outlets and all fuses on the connected amplifier were blown within a couple of minutes so the readings are probably close to the reality. I will contact PS Audio directly and hear what they say.


Did you use phase tune? In the setup screen.


He tried that too. I think the unit is screwed he even blew fuses in his equipment . A



I never tried phase tune but I don’t think it will do any difference.



Please, don’t use your amplifiers as test subjects.


After I realized what was going on with the P10 I haven’t plugged anything into it (except for the lightbulb).

I have added a ticket on http://www.psaudio.com/support/service/ but I am not really sure this is the right way to contact PS audio. The page more seems like an internal ticket handling function since I am allowed to choose the priority of the ticket and the owner of the ticket. Has anyone used the Service Desk ticket function?



I think you should get bob@psaudio.com in on this, email him directly.


Ok, I will do that.


You should get a response to the ticket (worked for me). You could also try Alex Paananen (alexp AT psaudio.com). He’s the customer service manager and the person who responded to my ticket.


I have got a response now to the ticket. Thanks for the help.