Is My Axe Fx Faulty? (Amp Hiss + Audio Clip Example)

Sounds like thermal noise. When you roll the volume off on your guitar you increase the resistance of the source (your guitar) greatly. 70% is about the worst possible position in this regard for a typical audio taper pot.

For example, assume your guitar has a 500K volume pot with an audio taper. At 70% you're about halfway on a typical audio taper pot so the resistance "looking into the guitar" is about 125K (250K in parallel with 250K). That's about 12 dB more thermal noise than if the volume pot was wide open (assuming a 10K pickup resistance).

Furthermore you've reduced your signal by 6 dB so there's a net degradation in SNR of 18 dB, which is huge.

So the answer to your question is "No, you are hearing the noise of your guitar. You can't beat the physics unless you want to reduce the temperature by 100 degrees".
 
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But if i understood correctly the OP states that the hiss is there even with nothing plugged in.same as mine.even with no guitar plugged in the hiss is there.
 
Sounds like thermal noise. When you roll the volume off on your guitar you increase the resistance of the source (your guitar) greatly. 70% is about the worst possible position in this regard for a typical audio taper pot.

For example, assume your guitar has a 500K volume pot with an audio taper. At 70% you're about halfway on a typical audio taper pot so the resistance "looking into the guitar" is about 125K (250K in parallel with 250K). That's about 12 dB more thermal noise than if the volume pot was wide open (assuming a 10K pickup resistance).

Furthermore you've reduced your signal by 6 dB so there's a net degradation in SNR of 18 dB, which is huge.

So the answer to your question is "No, you are hearing the noise of your guitar. You can't beat the physics unless you want to reduce the temperature by 100 degrees".
Thank you for the response!
The guitar I used in the example has active pickups, so I don't know if it affects your explanation.
However, this problem happens with every guitar I tried (passive too), and it also happens with the volume knob all the way up, I just wanted to accentuate it in the example.
Also I want to note that the problematic amp hiss doesn't get affected by the guitar's volume knob, and like I said before, it's the same even when the cable is not plugged to the amp.
 
You need to eliminate possibilities. Can you hear it through the headphone out? Try taking the axe fx to a completely different location and listening for hiss through phones. Since you say it happens without a cable plugged in this should be really easy to check. Try selecting different inputs. E.g. does it happen when usb input is selected?
 
You need to eliminate possibilities. Can you hear it through the headphone out? Try taking the axe fx to a completely different location and listening for hiss through phones. Since you say it happens without a cable plugged in this should be really easy to check. Try selecting different inputs. E.g. does it happen when usb input is selected?
Yes I already tried all of that.
Same thing with headphones, same thing with USB and rear input.
 
Did you take it somewhere different?

Anyway you should probably raise a support request.
It's a bit hard for me in my current situation to take it somewhere else.
I'll try taking it to different rooms when I'll have some spare time.
 
OK so today I tried turning off my PC, while listening to Axe with headphones plugged in directly, and no guitar jack.
The noise didn't change in sound or volume.
Weirdly enough it shifted a bit from the center to the right (the preset is completely mono), so I guess you could maybe say that the noise got a bit more quiet in the left channel.
 
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