Pitchfactor produces loud hum when running in stereo on two Vox AC30 amps

[bhmredspecial]

Dear sir,

I have a pitchfactor running in stereo for two Vox AC30s.

However, it produces a hum like a groundloop. I use the adapter that came with the unit.

Any help would be appreciated.

Laurens

[nickrose]

You will probably need to get a knowledgeable person to look at your setup. Any time you have more than one ground connection, you will get a ground loop (may be inaudible).There is a small possibility of it being caused by an equipment fault, but unlikely.

You probably have 3 grounds – Vox+Vox+PF. But, you don't want to go around disconnecting grounds without knowing what you are doing. For now, make sure that they are all plugged into the same powerstrip, with mains leads as short as possible, ideally tied together. This may help – if not, you will need to find a tech to look at it.

This problem can occur whatever equipment you have – it's a matter of how it is all connected.

[bhmredspecial]

Dear Sir,

The pitchfactor-adapter has no ground, so I guess only the Voxes are grounded.

Anyway, I've heard people running timefactors at two amps without any hum at all, it's maybe a good option for me to return to the store and test a second pitchfactor… if it has the same problems.

I've been running multiple voxes for quite some time now, so I know what you mean with groundloops. I really think it something inside the pitchfactor, as I can run my multiple voxes without any problems at all with all my other equipment that I have….

Cheers,

Laurens

[achaput]

Hi Laurens,

You are right that the PitchFactor power supply has no ground. However, in the setup you described the ground would be shared via the instrument cables between the PitchFactor and the two amps. A simple test might be to unplug the instrument cable from one of the amps and see if the hum goes away.

[jeffigueirinha]

Good morning, from Brazil, I have a PitchFactor and it has the same noise problems coming from the system, I used balanced cables and nothing changes, when I turn on the unit it works for a few minutes and then the noises start, I noticed that some effects accentuate the noises ( Harpegiador , Synthonizer , H910 / H949), already replaces the source, I used a sinusoidal UPS and it continues without conditions of use this unit, unfortunately.

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