2. analog
  3. 126134-46

Low level hum only with lp playback

Basic system:

VPI Prime turntable (cart is a Dynavector 20x2L) with
Purest Audio interconnects ( with integral ground wire connected to phono pre) to
Parasound JC3+ Phono Pre with
Cardas Clear Light Balanced Interconnects and separate ground wire connected to
BAT Preamp
REL R-r328 sub

I use an Eagle PSU with Roadrunner tach for speed control. 

So I'm getting a low level hum ONLY when the record is playing. You can hear the hum on the lead in groove - the sound gets louder as the volume goes up even if the music hasn't started.  However if the needle is lifted the hum goes away. 
I played around with the ground wires locations to no avail.
I've checked the leads to the cart for tightness and to make sure they are connected completely -they are. 
I've moved the speed control equipment to make sure they are no interfering. 
All my connections are tight. 

last_lemming

Showing 2 responses by jmcgrogan2

jmcgrogan2's avatar
jmcgrogan2
6,346 posts
 
Did you try to disconnect the ground wire?

I asked, because oddly enough when I upgraded from my Scout to the Prime, I also had a buzz/hum issue. I tried changing the ground around a few different ways to no avail.

Then I disconnected the ground, and total silence. I can't explain that, as the Prime is the first table that I've run, out of 5, that ran quieter with no ground connection.
jmcgrogan2's avatar
jmcgrogan2
6,346 posts
 
Wow! You've had this problem for over 6 months now???

https://forum.audiogon.com/discussions/vpi-scount-to-prime-now-static

Have you contacted VPI?
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