Fixing Up Old Thorens

Hi guys I recently purchased a Thorens TD 150 (MK 1 I think). I added a RB300 tonearm with Ortofon red.The initial test was very disapointing, with vertually no bass. Any ideas as to why this is happening? I have a decent amp and speakers. I am a joiner and am really looking forward to building a new plinth from maple and a lovely piece of ebony for the arm board, but my enthusiasim has waned with the poor bass level.

Tomjacksons, the lack of bass likely means that the platter is now too close to the top plate and you need to adjust the springs. There is a good tutorial at the analogdept site, and this post at Vinyl Engine from a former Thorens employee will also help you learn how to do this--http://www.vinylengine.com/phpBB2/viewtopic.php?t=7020&highlight=justage

Scroll down to the post by Violette. On that-auction-site the poster Violette (Joel) also sells wonderful lubricants and Thorens-spec belts for the various Thorens models.

Also at VE is a Thorens overhaul guide (authored by Violette) that you might print for reference, it's terrific.

Jim

to Tomjacksons :

I have the same experience with the Rega RB300 on another turntable. It seems to have a very "midrange" sound. Very weak bass. As far as i can remember speed accuracy = good treble and all the bass is essentially in the arm...

Make sure the rear of the arm is high enough too. If it is too low, bass modulation will reduce the tracking pressure, IOW weak bass.

Also make sure you have the cartridge connections correct. If one channel is out of phase, you may experience weak bass.