VPI Scout and cartridge hum

So I just installed a new AT 440mla cartridge on my VPI scout. I absolutely love the cartridge and I finally have stopped worrying about inner groove distortion. For some reason I have a slight hum with this cart, and I never experienced the hum with other cartridges. It is less noticeable when the music starts and at most normal listening volume levels. However in quieter parts I hear it more, and especially when I'm using headphones. I have my Scout grounded to my amp, so that's not the problem. If I touch the tonearm or tonearm wire or if I remove the wand off the unipivot it is worse. I tried removing the grounding wire, but that made it worse. At most listening levels it goes unnoticeable, but it's still bothersome. Any suggestions or fixes?

 

Are the four tonearm leads (clips) attached tightly to the pins at the rear of the cartridge? Or is there some looseness?

 

They are all attached as best as I can get them. Any more and it would be applying too much force. It seems to just be this cartridge, but I'd like to find a way to fix it.

 

Sounds like the same issue I was having with my Scout. I had motor hum. I reduced it by putting 3/8 window foam under the feet of the motor. VPI does not like to admit they have hum from their motor design.

 

Well, I never had any hum or motor hum with my Dynavector 10X5 mounted. I actually like the AT440 mla over the dynavector. It's a way better tracker. I do have a mouse pad under the motor, but I don't think the hum is from the motor.

 

I too, had an AT-440mla that hummed, when no other cart, regardless of price, hummed on my (DC motor) table.

Never did solve it, and finally had to return it, for a refund.

 

Also, when I touch the tonearm wand or headshell, or if I remove the wand from the pivot point, it accentuates the hum problem. If I touch near the lemo connector, the hum is not as strong...

 

I just realized that my TT interconnects are partially shielded, meaning they are not really shielded. Is there a way to fix this or around this problem, or do I need to buy new interconnects? I would rather not, since I invested a good amount in them and they are decent quality. Bump.

 

BLASPHEMY!!!!

 

Assuming this isn't one of the bad 440MLas (did you buy used or new?), I was having this problem on my Scout. I ended up finding that one of the leads was too loose on one the pins of my DL 103. It was looose enough to just slip on and off with no real force. It wasn't a matter of getting it further on the pin, but of how tightly it gripped the pin. Got a pair of needle-nose pliers and crimped it down some. That drastically reduced the hum. So if any of the leads have wiggle room, it might be worth pulling them off, crimping them a bit, and then putting them back on.

Shielding could be another issue, as you pointed out. FWIW, when I was swaping calbes around to find a hum, it turned out that the cheapo $3 Radio Shack RCA cables, presumably unshielded?, had no hum where nicer but unshielded (Grover and Morrow) cables did. If hum's driving you wild, you might just try some cheap cables to see if that'll help.

 

Nooooo do not crimp like that. Loose connections like that can cause havoc but try this instead. Take your leads off and put a toothpick in it. Crimp then around the toothpick. Those are very fragile (just like the ideal mastering by Steve Wilson) connections . the toothpick will prevent you from crushing them . will be a nice tight connection on the pins them.

 

Ah, good suggestion! I'll be sure and do it that way in the future if I need to.

 

Not sure where you get that idea. I've communicated with VPI about hum (actually vibration) and they recommended the mouse pad fix. No denial there.

John K.

 

Just a thought...I had a similar problem once. Eventually I realized that the motor was barely touching the plynth.

Again, this probably is not the issue, but it's a simple check to make sure.

 

I had a hum problem on my VPI Traveler. It took some adjusting/twisting of the cables right out of the turntable to fix it.

 

I assume the hum is only with the TT as the source. Check your grounding. Are you grounding the TT to a preamp or phono amp? Is it grounded to the Amp and is it grounded to an exterior ground?

Good luck with it. Hum can be a booger to cure.

 

Please don't get me wrong, I love my Scout I has been a pain tweaking out the hum. I didn’t say they denied it just they don’t talk about it much. It’s rare I’m able to call them during their phone hours but when I have they have been fantastic.


As far as I’m concerned a mouse pad is a big Band-Aid and all these years they just can’t fix the issue. By the way the window foam worked better than a mouse pad. In my situation.

 

My Scout has a ground wire attached from the TT to my integrated amplifier. Do I need another grounding wire from the integrated amp to somewhere else?

 

Have you taken the first step and unplugged the motor to see if you still have hum? If there is no hum, plug in the motor and don't turn it on and try the test again. Still no hum? Then it must be the motor inducing noise into the cartridge, at which point you can try motor supports, etc. The only way to track hum issues like this down is to work methodically through all of the possible sources and write down what you hear at each step.

 

Just an update: I have been continuing to use my AT440 mla. The hum is faint and tolerable and I can only hear it when there is no music playing or during quieter passages. I unplugged the lemo wire to my VPI junction box last night and the hum disappeared completely. So now I know that it is tonearm/cart related...I think. Is there any fixes to this? Any modifications to the tonearm or junction box?

 

Did you try disconnecting the ground wire to see if that resolves the hum? It sounds like a ground loop to me.

 

There is a ground wire connected to the VPI junction box to the back of my integrated amp. If I remove the wire, the hum gets louder and worse. The wire is definitely improving it.

 

You might want to try the VPI Forum for more/other suggestions. There are a lot of really knowledgable people on there, including the designers. At least try a search there. My scout 2 is dead quiet with Sumiko BP and now BB, no mousepad. I hope you can get your AT cart quiet.

 

I had hum on my HW-19 MKIII - tried a bunch of things to fix it up. I ended up with an external phono stage that cured it. Ground loop, maybe, but 2 other tables with the same cartridge didn't hum at all. I would venture a bet it's a whine more than a hum? If you can record samples and check out the files in something like Izotope you should see it dead nuts at 60Hz - this is motor noise that the ground just can't cancel out. I figured it out by recording samples.....motor off, needle up and down (no whine) - as soon as the motor was turned on, and with the needle up it was there....and got worse with the needle down as contact was made. Best of luck.

 

Hum in a 2,000$ tt, blasphemy.

Hum in a 400$ project carbon, well it's just an entry level tt soooooo...

Interesting.