Noise hunting trick on TD124

[Telemann]

A little noise-hunting trick I am using may be of interest. My arm can be lowered so that the needle rests just to the left of the libelle (bubble level).

That way, the arm becomes a transponder for the noise of the machinery that comes through to the arm.
I've found that using this plus speed changes, helps me isolate the source of a noise. Sometimes, it's hard to tell whether it's the motor/motor pulley, belt, step pulley or idler wheel/platter that's the source of a noise that comes through.

If the noise changes in period when you change the speed of the platter, then you know it has to be the idler wheel/platter that's generating noise.

If the noise remains constant, then you know it's somewhere from the motor to the step pulley the problem lies. I can then experiment in stages. For instance, by removing the belt - if the noise remains, it's in the motor assembly. If it's gone, it's in a later stage.

Add belt - if noise appears, it's either the belt or the step pulley.

Add idler wheel - if noise appears, you know it's the source - either from the contact with the step pulley, or due to how it rests on its pulley.

Add platter, and you know it's the interaction between idler wheel/platter if the noise appears.

Be very careful with the arm and needle. If your arm doesn't allow this due to limitations of the mount, don't force anything.

But this method has helped me eliminate a lot of noise from my turntable in just a few days. I now have idler-wheel/platter noise to deal with, and it has a period that is equal to a little vertical wobble in the idler wheel. So if I can get rid of that wobble, then the noise (which is now very low at high amplification after greasing the idler wheel bearing) will be constant. (I began with a quite loud conga heartbeat from the idler-wheel, so there's been a lot of progress.)

This also helps me focus on noise that gets through to the needle and amplifier. I have the regular Thorens motor whirr that comes with a new belt, but that will eventually disappear, and has also gotten a lot weaker after two weeks of use, after stretching the belt.

But using the needle to diagnose the location of a noise helped me target my efforts significantly. I understand some are also using the clutch to stop the record, and then dropping the needle on to it, but I think that will give misleading results, as the clutch plates will possibly be transmitting noise that is not there when the top platter is running freely without being in contact with the plates.

I now have to see if I can get rid of that vertical wobble on the idler wheel, as I will then have a regular noise, and at very low strength coming through. I'm using loud amplification - not quite the amp's max, but then I never listen at the level I'm using for the test.

(My player's actually recently been refurbished, but was quite noisy when it came to me compared to how it's playing now.)