VPI Classic hum


Got mine a few weeks ago. Installed it with a high-output Benz Ace H cartridge. Loved the sound but there was a hum when I turned the preamp volume past the 10 o'clock position. Later changed to a Clearaudio Concerto, the hum was quieter, but wouldn't go away no matter what I tried.

Then I read the manual closely, and it said something about using shielded interconnects. So I tried a pair of Rega Couple wires, which are made from Klotz cable, and are shielded.

And you know what, the hum just vanished! Now I'm at peace ...

Just to share with those have hum issues with the Classic. Do share your solutions.
bassraptor
It's just physics. The motor is too close to the cartridge. They either need to shield the motor better or move the motor farther away. Sure certain carts will be more immune to the effects but you should not have to worry about this on a product this mature.
The latest versions of the Classic tables now have the motor mounted at the rear of the table and farther away from the cartridge. Perhaps this helps with some motor/cartridge hum interaction.
Harry has designed a new rear counterweight that eliminates the headaches that are expressed on these pages. I have replaced the simple dropped counterweight that first was shipped with my VPI 3D arm, and Harry has since shipped me his new weight. It took me less than 10 minutes to get the arm squared away with greater perfection than I ever could have done with the old weight. I am pretty sure this new counterweight would work with any VPI arm - not just the 3D. Get in touch with VPI.
Brf - Yes, I'm think replacement of the motor in the new version of the Classic 1 will counter that issue.

Stringreen - How much does that new counterweight cost?
Sarcher30, I quite agree. As far as I'm concerned, it is unconscionable that a product as mature and pricy as a VPI turntable should have a "hum" problem. That problem should have been fully addressed years ago. Just as much as any other fundamental design flaw, it significantly degrades the overall performance, and respectability IMHO, of an otherwise fine product. To perhaps make matters worse, both surprisingly and not the output of the VPI SDS is unbalanced even when it is plugged into balanced power. *Sigh*

The above complaint not withstanding, utilizing balanced AC for the whole studio, including all fluorescent lighting, reduced the overall phono system 60 Hz hum by about 15 dB. It's still there and I can see it and measure it, but it's now at a level that is essentially inaudible.

(BTW, my computer is not on balanced AC. It's unncessary. The computer is both physically remote and electrically isolated from the rest of the system by using Toslink connections which are, of course, non-conductive.)