View Full Version : Thorens TD 160 earth loop???

Dave E
27-04-2008, 23:44
Can anyone help?

I have attempted to replace the TP16 arm on a Thorens TD160 with a Linn Basic Plus. I have rewired the arm and replaced the phono cable (both silver).

My problem lies in a persistent low hum, which I presume is an earth loop. I have earthed the arm, the chassis, sub-chassis and even run an earth from the negative cartridge cable......And still I have this damned earth loop. #

Can anyone help???


Dave E

25-10-2009, 07:35
I used to have a Thorens 160. It has an internal earth wire and doesn't require an earth wire to the amp. Same goes for the Dual 621 where I cut off the old DIN connnector and soldered RCA plugs to the phono cable. No extra earth wire needed here.
I can't say what's necessary if you swap the arm. I guess the original TP 16 tonearm of the 160 is connected somewhere to the internal earth wire which you can see if you open up the deck and which leads to a place near the bearing. I'd try the same with the Linn arm if possible.

Good luck.



25-10-2009, 09:03

Did you use shielded wires for the arm? Unshielded wires can pick up hum from the TT motor, and have to be routed away from it.

Also sounds like you have more earths than you need.

25-10-2009, 09:32
This is from a bod who set up more TD160's with different arms than I care to remember...

The 160 as a chassis ISN'T earthed!!! With its own arm, there was a little shorting link on the audio terminal block connecting the earth of one of the signal leads to the chassis. Not good but cheaper than a dedicated earth wire.

The TD160 should be done accordingly and you shouldn't have any problems - The sub-chassis is connected via a flexible grey wire to an earthing point near the arm. The little arm earth wire is too long to connect to the main-bearing point, so connect it to the point near the arm base. I used to scrath the tag and solder the bare wire to it, but you could just screw the tags tightly to the plinth.

Once this is done and the deck set up to give free bouncing (tighten the top plate corner screws too) the the deck will be earthed to the amp via tha arm's earth lead.

I'd also suggest that TD160/Rega combinations may be a little bit improved by connecting an external earth wire wseparate from the arm-earth. It's so long since I've tinkered with one though.

Rare Bird
25-10-2009, 11:56
If you have earth link between Sub chassis & top plate

Arm lead earth to top plate also an arm lead earth to pre amp ground terminal should be no hum.

If your using a Magnetic Cartridge you arm signal wire must be sheilded, If MC not important..If still persists try another cartridge.

25-10-2009, 12:59
The Thorens decks can be utterly quiet when earthing is sorted.

19-01-2010, 18:35
Can any one help. I have a TD160 with TP16 pick up arm. I have recently bought a NAIMUNITE for which I use a NAIM preamp. getting mains hum which NAIM say probably needs the pick up arm earthing via the preamp. Any one tell me how to do it?

19-01-2010, 19:31
Before you work on the deck's signal wiring (which it'll need by now), try connecting a cable from the earthing point of the phono stage to the mains (say, the turntable mains plug earth pin). This may sort it completely.

If you don't wish to do this and aren't any good at soldering under/inside the deck, get your dealer to do it for you. They've made enough profit on the Uniti and phono amp, let them earn it....