Finding a replacement drive belt
This page will test and review different Thorens replacement belts that are available from vendors on the web. The reason for this is due to reports of incorrect belts being sourced by vendors. Think of this page as a test of a vendor's ability to source a correct part.
Introduction:
Thorens suspended turntables isolate the platter and tonearm from electric motor vibrations by utilizing a separate chassis suspended by springs, and by an elastic drive belt. In the case of the TD125/6, 14x, 15x, 16x models, three conical coil springs are located under the floating sub-chassis. The TD125/6 differs from the others because it supports the springs from below by adjuster cups located in a metal tray. The TD 14x, 15x and 16x models hold their springs on three steel studs that hang downward from the top plate. In each case, the springs are located below the platter bearing.
In all of these designs, the belt itself is an important part of the overall suspension scheme. The job it must do is complex. The flat belt drives the inner driven-platter by friction. In order to produce exceptional sound, the belt must maintain constant velocity between the motor pulley and the driven inner platter. Any belt slippage or variation in rotational speed of the driven-platter caused by belt action will degrade sonic output. At the same time, the belt is relied upon to allow independent motion of the suspended chassis. In truth, the belt will exert some influence on the action of the floating sub-chassis. Be sure that all this was taken into account by the original designers. The belt is an integral part of the suspension design.
Thirty years later we find many of these turntable models have held up well over the decades and may only require a belt replacement. Unfortunately, the company that built these tables no longer exists.
above photo: some NOS Thorens drive belts purchased from a Thorens dealer in Athens (2004). pn# Z6800574 (thanks to Thomas Kamvoussioras for sending in this photo)
Question: How important is proper belt selection to the performance of these old tables....?
Answer: very. We want to find replacement belts that exactly match the physical attributes of the original equipment.
Question: is this even possible?
Answer: We mean to find out in the belt reviews listed below.
Thorens drive belt part numbers:
|
Drive belt |
|
|
TD 180 |
Z6180003 |
|
TD 190 |
Z1272489 |
|
TD 280 MKIV |
Z6800580 |
|
TD 124 |
ZCB96500 |
|
Prestige |
Z6826130 |
|
Referenz |
Z6824209 |
| TD 105-126MKIII/145-146V/147/160-166VI/316-325/280-280III/290/295 |
Z6800574 |
belt 1) 
click on thumbnail to see full size.
In service for 28 years. This is the original belt supplied with my TD160. (60x mag.)
belt 2) 
A new generic replacement belt of unknown origin. (60x mag.)
belt 3) 
A new replacement belt from Rolf-Kelch Electronic (60-x mag)
Reader's experiences with belt replacements. Link here. Consumers rating vendors, and vendors rating consumers...?
Belt Reviews
Rolf-Kelch Electronic GmbH
Generic belt, unknown vendor.Vendors yet to be tested:
Q Audio: http://www.qaudio.com, has genuine Thorens replacement belts with the Thorens Logo. Price is $25.00 plus $2.00 USA postage/delivery. I have not yet tested one of these belts but this vendor has been an authorized Thorens dealer for the past 25 years. Bob is good to communicate with via email.
Turntable Basics, http://www.turntablebasics.com/ cross references US built substitutes at $15 each. I have not tested one of these belts. Reports by other users suggest a wider belt with a thicker cross section. Some have reported finding a workable size by trying progressively longer belt lengths until good function is achieved.
Elex-atelier: http://www.elexatelier.com/thorens.htm Belts Thorens models are $24.90 each. I tried their belt for a TD150. (LP Gearbelt #THO032)
Dimensions of their sample: width: .200 x length: 20.50 x thickness: .026 inches. These are incorrect dimensions for the TD150. Most notably width should be: .16 inches. The belt lightly rubbed against the derailleur lever in either speed because of its excessive width. Motor noise was high due to excessive tension. I can get this level of inaccuracy for less than half the price off ebay...!