Humming noise coming from TT

[Ben Culley]

Hi All,

I have recently finished building a turntable with a linear tracking tonearm.

I have set up everything and I noticed a humming sound through my speakers when I set down the needle onto the vinyl.

I have realised that it is caused by the Aquarium air pump. When I turn off the pump there is no noise. I have tried plugging there pump into a different socket on the other side of the room via an extension lead but I am still getting the humming sound when it is conected.

Can anyone help me with this? Do I need to get some sort of filter to stop the humming noise?

Thanks in advance

Ben

 

[indianajo]

I suggest you take the air pump out of the turntable and put it somewhere else. Air can be moved around in flexible hoses. A tank can act as a local accumulator. Motors and transformers can emit magnetic flux at the line frequency.
Amp builders spend a lot of money to encapsulate transformers in steel cases and behind additional steel walls from the high gain circuitry. A magnetic phono cartridge and the wires from it end directly in a high gain point.

 

[Osvaldo de Banfield]

I have set up everything and I noticed a humming sound through my speakers when I set down the needle onto the vinyl.

Surely the magnetic vibration (Magnetostriction) of the core of the pump's iron core is transmitted via the TT to the disk and reproduced by the capsule. Increase vibration isolation or more over, change one of them away the other.

 

[Ben Culley]

Thanks very much for your replies.

I have solved the problem. The pulsating air from the pump was causing vibration in the air chamber. The stylus was picking this up.

I have connected the air via a ‘Smoothing tank’ and now there is no humming!

Cheers

 

[Audiofirst]

Thanks very much for your replies.

I have solved the problem. The pulsating air from the pump was causing vibration in the air chamber. The stylus was picking this up.

I have connected the air via a ‘Smoothing tank’ and now there is no humming!

Cheers

That's a serious turntable you have there, Ben!