Thorens TD 126 MK II (1976-77) with SME Series III B Oct 23, 1982 Charlotte NC

Thorens optionally supplied Series III
Stereo Shoppe warned against MK III

Sites of most interest: vinylengine, theanalogdept and Vinyl Nirvana
vinylengine forum schematic
Rare and Elite Thorens TD-126 MKII
2004-8, 2012 reviews

Thorens Family Tree at theanalogdept.com
Gallery of rim, belt drive models TD 150 preceded TD 125

TD 124 (rim drive liable to vertical rumble) absurdly popular 1957 - 1968

• Rim drives are liable to rumble, in my experience, and idler wheels replacement is problematic.

TD 125 mechanically similar to TD 126 - chassis comparisons
TD 126 (1974) and MK II (1976) models continued to use the 16-pole AC synchronous motor from the TD 125 MK II
TD 150, 125 and early 126 use 10mm bearing; TD 126 MK III and later use 7mm bearing.
“From my taking the bearing off a TD126 Mk2 and replacing it with one off a TD126 Mk3 two differences were noted.
Both were 10 mm The earlier Mk 2 had a one piece bronze sleeve, and metal thrust plate in the bottom.
The Mk 3 had a two piece sleeve to allow an oil pressure doughnut half way,
ensuring the bottom did not dry out in worst cases of no care.
The Mk 3 also had Teflon as the thrust surface.”

Image of TD 125 springs in plate on which sub-chassis rests

Suspension set-up 3-spring design shared by AR, most Ariston, Linn LP12, Systemdeks, and Thorens TD 125, 126, 145, 147, 150, and 160
Suspension Adjustment videos

Stylus alignment AKA Zenith

Most writing about cartridge alignment is BS.
First, it is stylus cantilevers that want alignment.
If a stylus is not aligned in its cartridge body, it needs replacing.
Of course, a (non-conical) needle may be misaligned in its cantiliver…
Facts:

• For pivoting tonearms, stylus cantilever alignment perfectly tangent to record grooves occurs at only 2 places along record radii.
• Audio-Technical writing that different protractors are required for different effective tonearm lengths (needle to pivot distance) applies only for arc, which does NOT satisfy alignment.
• NOTHING in this diagram is useful for accurate alignment:
  
• Perfectly matching some overhang or arc is incidental to cantilever alignment.
• These pairs of parallel lines (really, just center lines) are ALL that matter for alignment:
  

IMO, if stylus cantilever cannot be seen well enough to align with protractor, get another cartridge.

Tracking distortion is phase-shifted, compared with harmonic distortion typical of active electronics:

• That phase error should affect perception of stereo imaging..

Relevant alignment protractor differences are only about what tracking distortion metric gets minimized:

• RMS (Loefgren AKA Lofgren B)
• highest (Baerwald AKA Lofgren A)
• towards the center(Stevenson)
  FWIW, the argument for Stevenson is that classical music typically gets more dynamic towards the center…

Increasing tonearm length reduces tracking error magnitude, but longer arms have higher effective mass,
which is problematic for high compliance styli and e.g. warped records.

vinylengine forum

overhaul guide
“you don’t want a thorens”
triage needed - clean and re-oil bearing
spindle/bearing oil - mostly BS
motor or pulley problem? bent shaft
suspension video - ddarch
index and paper shim platter
strobe ring
strobe mirror
first day fixes
TD 125 uses same springs
spring sets
MK II motor matches MK IV and 127 MK 1
motor control circuit
motor start problem
motor thrust bearing DIY
motor clutch slipping
strobe issues
Cartridge for SME 3009 series 3
SME Series III Reviews
load capacitors in RCA leads(!)
Stereophile SME review
haters, but really some matching cartridges
other high compliance cartridges
AT OC9III would work fine
High Compliance Cartridge recomendations
Ortofon SME 30H armwand
Ortofon 30H: sty30 vs. sty20 or go crazy: sty40