2. analog
  3. 1186090158

Ground Hum

I need some suggestions eliminating ground hum from my VPI Scoutmaster.

Cart is a Shure V15Vmxr (or whatever it's called)
Tone arm is JMW9 with stock wiring
Preamp is Dynavector P75.

I have tried a few different cables ranging from monster cable to cheap stock audio cables you find with most electronics. Makes no difference. If I touch the tone arm wtih my finger, the hum gets louder. If I touch the gold connectors on the back of the turntable the hum goes away. Touching any other parts of the tonearm output block or the preamp causes hum to get louder. Any suggestions?

A_L
arnold_layne

Showing 5 responses by arnold_layne

arnold_layne OP
141 posts
 
I have found a way to eliminate the hum. Though this may not be ideal, the solution was simple. I ran a strand of bare wire from the ground lug to one of the rca output jacks of the tonearm connection block on the rear of the turntable. Hum is now gone.

A_L
arnold_layne OP
141 posts
 
Sorry failed to mention, yes the ground wire is connected. Disconnecting it made it slightly louder.

A_L
arnold_layne OP
141 posts
 
There's already a ground wire running from under the bottom of the tone arm assembly under the turntable to the grounding lug. I have another wire running from that grounding lug to the ground on the P75 preamp.

A_L
arnold_layne OP
141 posts
 
I've been wanting to upgrade the cart anyway, so I will give that a go. I have tried different cables, Monster Cable to inexpensive standard audio cables, no effect. I'm leaning towards the cartridge. I've had the cart on a previous table before I got the Scoutmaster but I did buy it new just as the Shure V15 series ceased production.

A_L
arnold_layne OP
141 posts
 
Thanks for everyone's input. When I have more time I will try every option given here until I narrow it down.

A_L
More to discover