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What cable do you use from input socket to volume pot

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I was wondering what you cable you use to connect the input socket to the volume pot (or grid).

In the past I have used shielded single core, grounding the shield at the pot and at the input. Is this the best way to do it?

Other alternatives that I can see would be -

1. Non-shielded hookup wire

2 Shielded duel core, with the internal wires connecting the pot and the input socket with the shield grounded to the signal ground wire somewhere early along the chain.

Also, any favorite cables and recommendations of suppliers?

Cheers,

Rob
 
Rob, I use a twin core coax. One core used for signal. One core used for signal ground. I attach the signal ground core to the ground bus at the point furthest from the power supply. The coax shield should be grounded at ONE END ONLY. I normally bond the coax shield to the chassis at the input socket. Also, make sure that the input socket it properly isolated from the chassis.

I just use cable from Altronics/Jaycar etc.

Some people make the signal ground connection to the chassis at the input socket.

Good link to grounding schemes. Since following this advice I have had hum free amps...

http://www.aikenamps.com/StarGround.html

Cheers,

Chris
 
Ex-Moderator
Joined 2004
The coax shield should be grounded at ONE END ONLY.
This is true IF you use two-core shielded cable as described, and the outer braid is used only as a shield.

However, when using single-core shielded, with the outer braid as the ground connection, I found significant hum problems unless I grounded the outer at BOTH ends. Must havr been as ground-loop problem, I suppose.
 
ray_moth said:

This is true IF you use two-core shielded cable as described, and the outer braid is used only as a shield.

However, when using single-core shielded, with the outer braid as the ground connection, I found significant hum problems unless I grounded the outer at BOTH ends. Must havr been as ground-loop problem, I suppose.

Yes Ray_moth,

I have found the same thing. I have used the single core wire in the past and grounded at both ends on the basis that the shield was carrying the signal, the input socket being isolated from the chassis. This worked very well with no hum but I am going to go duel core, if for no other reason that it is somewhat awkward to solder the shield to both ends neatly.


Geek said:
Hi Rob,



Sometimes you can run across an office upgrading their LAN system (or an old one being torn down) and you can snag a good length of twinaxial for nothing to cheap.

Cheers!

Thanks Gregg, I have already found some great looking wire on that very useful site that we all know, which is silver plated and looks very nice - I have little doubt that it is sonically no better than the local stuff at Jaycar but it looks great!

Thanks for the help so far.

Rob
 
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