[Audiofiler]

I have noticed on my friends recently purchased Thorens TT a "duwh.. duwh..duwh.." sound that is only audible once the platter reaches the intended speed. Removed the platter,slip mat, along with center circle mount but still the sound utters away after about 6 or so seconds of spinning.

Does anyone have any suggestions on what to do? My Thorens is dead silent and I have never encountered this particular error on mine. And though simplistic in design,the TD160 I would imagine someone here could possibly shed some light on this matter,
thx for reading in advance

 

[memepool]

It could be that the belt is snaging on the guides around the pulley since it only occurs when the deck is upto speed. Watch it's path carefully with the outer platter removed as you described above.
Many replacement belts which are described as Thorens compatible are too thick or wide and can cause problems like this. turntablebasics.com will supply a range of belts which match and help you tweak it until you get one that fits just right. It's also important not to get one that's too tight as it can strain the bearing.
Linn LP12 belts are also a good option as they are pretty much identical, unless of course you can track down an orginal Thorens branded belt but these are hard to find nowdays.

 

[Uncle Erik]

Probably the belt, but have you cleaned and oiled the bearing lately? It never hurts.

 

[Herandu]

Put a small coin or paper clip etc on the furthest edge of the platter. Now start the TT and see how many times per revolution of the platter you get that noise to appear.
If it is once per revolution, it is something that is related to the platter outer edge.
If it is 2 to 3 or so, then it is something that is snagging on the belt as the turntable is turning.
If it is several per revolution, then it is likely the motor.

 

[Graham Maynard]

Take off the belt and wash gently between your hands with detergent under the kitchen tap.

"duwh..duwh..duwh.." = not enough side tension on motor pulley/bearing.

Washing the belt fractionally tightens it, as well as preventing any slip or slow start-up.