Please watch this video, PS2A introduces hum audible thru the speaker even if the amp is off, is this normal level of noise?
Hi Rojaslaz,
Welcome to the forum!
First, I am going to point you to the Power Station troubleshooting section of the forum:
Second, I’ll explain the whole myth about “I’m in the same outlet as the amplifier so there is no ground loop”. That’s absolutely not a guarantee there won’t be a ground loop. Ground loops can occur for many reasons. Also, I’ve seen some pretty crazy wiring when it comes to home circuits.
Third, why have the amplifier off when you are testing?
Fourth, what cables are you using coming from and going to the amplifier? Those look like standard audio cables. Also, make sure those right angle plugs aren’t touching each other. That’s another ground loop source that can cause issues.
I want to get you back up and running as quickly as possible. Let’s try to get this solved together. Let me know about the questions above and let’s get you playing music again.
Thank You,
Terry
thanks for the quick reply! the cables are mogami speaker cables. i just switched the right angle ones to standard straight ones, no difference. is the level of noise you hear in the clip normal to you?
Thanks so much for sharing the video—it’s really helpful because it gives us everything we need to get a clear picture.
The first few minutes, where you walked through your experience and setup, were super clear and really helpful.
At the end, there’s a little bit of guitar playing at the lowest possible volume and yes, you can hear the hum as well. But if you increase the volume, the hum will disappear into the background and that’s pretty normal for any tube amp. So are you wanting to play at very low volumes, is that your application?
I know some people are more sensitive to hum and would rather it wasn’t there, and I get that—it can be a bit annoying and I can’t say anyone wants hum! But at reasonable volumes it inpercetable, and at very low volumes it’s really just something we have to live with.
Hello Dan, thanks for the reply.
Yes you are describing my issue very well. The PS2A is introducing a hum which is 100% coming from the unit, that’s why at the beginning I had the amp OFF, just to underline the fact that this hum is caused the PS2A. My need is to confirm that this hum is within factory specs for this unit. could you please confirm that this noise is something you heard before and it’s normal?
Also, the reason why i wrote in this forum is because ive owned this unit for maybe a year (im the original purchaser)and I never noticed this hum,and I always play quietly. I would have noticed this before but somehow only noticed it now as I was rearranging some stuff in my home studio.
Hi Rojaslaz,
The reason I asked why you had the amplifier off was to understand your process. I was wondering if you had unplugged the amplifier from the Power Station (just the “Amp In”) before and the noise was still present in the cabinet. If you get a chance, can you try that as well if you haven’t already?
I will say it is very hard for us to judge if something is “normal” or not from a video. We can say, a small amount of hum or noise is normal for all tube amplifiers. Then we get a video of it and because of audio compression, it sounds like a 747 taking off in the living room. Sometimes, it’s the opposite. We’ll get a video that we can barely hear anything and the customer is telling us it sounds like a herd of elephants. They could be right, it’s just very hard for us to say. Like Dan said, some people are very sensitive to hum.
You did hit on something that I’m wondering about. That’s that you didn’t notice it before and then you recently started rearranging. I’m wondering if it may be positional within the room. Have you tried to move it since? Where was it before? It may give us some more insight into what may be happening. I apologize for any inconvenience.
Thank You,
Terry
what I changed was some cables, not the position. since then I tried positioning the ps2 on different places in the room and simplifying the cableing to the bare minimum needed (one amp, one ps2) , all with the hum present and noticeable.
i understand videos can be confusing, i guess my question to the team is: does the ps2-A introduces a hum into the signal path by design? if yes, how much is acceptable? I feel that the hum im hearing would make it really hard to record a cabinet with a clean guitar going into the amp. without the ps2a in the chains my sound is quiet, with the ps2A i have a hum that would indicate heavy guitars and loads of gain.
Hi everyone,
To behonest it is pretty normal. But it sounds way worse on the video because:
- the microphone gets pushed really close to the speaker grill
- (like Terry says) all bets are off on perceived volume because of compression
But even in-the-room:
- It’s sitting in a silent room
- Neither the amp nor the Power Station are amplifying any guitar signal
It is not unusual to have hum. When you actually use this to play, does it prevent you from using it? I think it would be a waste of time and money to investigate this any further.
Sometimes hum can be caused by preamp tubes (noise on heaters gets coupled to cathode). So you could explore that. But I don’t think that is what is happening because preamp tubes last years.
There is an FAQ (in the FAQ section) on how to do that if you want to take a look at it.
This depends on the volume level. I noticed that during the video clip the volume was basically as low as possible (I could hear the guitar string too). The reason why this can be deceiving and cause concern is because you are hearing the noise floor of the amp and this never improves – this is the same for all amps. There will always be a minimum amount of hum that makes it to the speaker.
However, the volume of hum is actually not important. What is important is the ratio between the level of hum and the level of guitar signal in the room. When you turn up the volume, the guitar signal gets louder faster and the hum becomes imperceptible when you are actually playing, clean guitar tone or not.