Need help with low noise

I have a turntable hooked up through a Ion Mixmaster box to my Mac. When I’m in Audacity and the USB is plugged into my Mac, even if the power is off on my turntable, if I hit the record button there’s a small constant noise being recorded. I’ve tried everything I can think of. Can anyone help?

Is the turntable electrically grounded ?

WC

Yes, there’s a ground cable from the turntable to the Ion Mixmaster.

What is the character of the noise. Can you post a sample?

Yes, there’s a ground cable from the turntable to the Ion Mixmaster.

Does the noise get massively worse if you take the ground cable off?

The Ion Audio iMX05 MixMeister Express DJ is a USB connected device. Does the constant noise sound like this?

Koz

I attached a sound file. Part way through I disconnected the ground to show the difference. The sound at the beginning is a low clicking sound.

Ah that’s a different one. Not the hum or whine that Koz and I were expecting.

Can you post of photo of your “Mix Master”, or a link? When I google search I find several products under the name “mixmeister” with varying capabilities.

Does your unit have a headphone jack? If so can you hear the noise directly in connected headphones, or only in the resulting recordings?

I note that the noise is only in the right channel. What happens if you disconnect the right-channel line from the turntable?

There is some on the left, but it’s super low volume.

There’s another oddity. I expect the hum level to go nuts when you disconnected the ground strap and it didn’t.

We don’t know anything about the turntable, either. Is that USB connected by any chance? What’s the chances you outstripped the USB’s ability to power stuff?

Koz

The burst of hum is pretty much what I would expect.

A bit of google searching turns this up as the most likely candidate for the OP’s gadget:
http://www.gadgetreview.com/mix-meister-usb-recorderconverter-from-ion

Which is interesting because as far as I can tell the one thing the product can’t do is “mix”…

That would imply that the OP has either a conventional turntable or one with a built in phono preamp. With the fact that there was hum when he disconnected the ground I’m guessing no preamp in the turntable and the box is in phono mode.

So to graymatter: The trick will be to determine if the noise is coming from the turntable (possibly a motor acoustically coupling into the cartridge), or far more likely a defect in the USB converter (I which case the cure is to just go buy a new one such as the Behringer UFO202). Do you have any other equipment (stereo receiver, DJ kit, etc) with a Phono input that you can plug this turntable into and test?

You might also try unplugging the turntable’s RCA connections at your “mixmeister”. If the noise is still there then for sure the problem is the interface. However if the noise goes away it is likely the turntable but not guaranteed. There are more subtle failures of the interface that might generate this sort of noise only when the turntable is connected.

I just want to say thanks for all the help, truly appreciated.

I disconnected the RCA jacks from my turntable to the Mix Meister and the static seems worse at least visually on the Audacity meter. Does that mean it’s the Mix Meister?

The Mix Meister that was posted via the link is the correct one.

My turntable is a Technics Sl-1200MK2, which does not have a preamp.