Hi I have a recently purchased PS-2a.
When switched to ‘Operate’ there is a hum which makes the unit unusable - I need it for use in my studio.
It is not a ground loop issue - the accompanying clip was recorded with the PS-2 only connected to AC & a speaker cabinet.
Hey Bluesman welcome to the community 
Sorry to hear this makes it unusable. You have a PS-2A which is the latest version of the Power Station and has improvements to the power supply in terms of filtering.
I can hear the hum when in Bypass (this is noise from your valve amp), and this increases when you go into Operate because you have the noise of your valve amp plus the noise of the PS-2A’s valve amp on top.
Sometimes this can be improved by detecting and changing a tube that is particularly noisy. The noise can occur due to random variation in the manufacturing process of tubes that increases the leakage current between the cathode and the heater element.
When cables carrying small, single-ended signals are close to PS-2A’s transformers, this can also be a cause of noise because the changing magnetic fields induce a noise voltage in the conductor.
But you sound like an experienced user, so I am sure you have tried different cables and moved them into different locations to see if the noise can be improved. A photo of the setup might help to see if I can catch anything, however unlikely. And if you do have a different ECC83 you could try swapping it in: How do I change the tubes and fuses in the Power Station
However, I get the feeling that these will probably not improve things too much. When you are playing the guitar, how is the hum? It is quite hard to gauge from the audio above the true levels. Are you based in the UK? I wonder if you are close to me; you could always pop over, and we could compare it against my PS-2A. PM if interested. I am about an hour from London.
Regards,
Dan
Hi Dan
Thanks for coming back to me.
There was no amp connected when I did the sound clip – just the PS-2a connected to a speaker cab, nothing else.
I wanted to keep it as clean as possible.
I already checked the tubes, in case they had been damaged in transit but everything is fine.
The hum is audible in quiet passages when recording.
Yes, I am experienced, having produced/engineered/ performed with major acts over more years than I like to admit!
I have owned a PS-2a before (it was stolen) and it didn’t have this problem.
I’m in Bedfordshire.
Thanks again.
JV
Hey
OK, I see what you mean now. Operate does draw more power from the power supply than when in bypass mode, so this could explain it. I suppose the only thing we can really do is get it serviced to investigate what is going on. I can PM you the details of a UK based tech. or if it is still under warranty you could request the dealer organise it for you? Where did you buy it from. We are not too far either, I’m in Newmarket.
Really, stolen. Annoying …
Hi Dan
I bought it from Peach Guitars, and they seem keen to have me deal directly with Fryette so I guess there’s no point in going back to them.
I purchased this PS-2a on 18th September 2024 so it is well within warranty.
Unfortunately, I didn’t get around to using the new unit until a couple of weeks ago so didn’t spot the problem inside the return period.
Bad mistake I should have checked it.
Yes, please let me have details of your tech., I would really like to get this resolved asap if possible.
Thanks for your help, Dan.
Have a great Christmas.
Cheers JV
Hey JV
Yes, that makes sense we can support the product better than they can. I am pretty sure that to become a Fryette dealer they agreed to handle warranty repairs. So you could ask, but I’ll PM you repair tech. info anyway.
Regards
Dan
Exactly the same problem with my PS-2a. I bought it from Thomann (Switzerland) and sent it back for repair. Thomann returned it to me saying the hum is “normal”. There is also mechanical noise when switchen to the operate mode.
Is there a fix for the issue? Several forum members have reported the hum problem already.
Best
Lorenz
We would need to get our hands on one of these noisy units to evaluate it and then see how it compares to units we think are typical. With that baseline, it becomes more than conjecture and opinion and opens the possibility for investigating improvements.