TD124 mkII w/ 9" armboard - max arm length?

[nickbaba]

Hi all - I'm soon to become the proud owner of a TD124, after several happy years with my 401.

I'm planning to mount an Audio Creative Groovemaster on a 9" armboard, cut for SME style mount. The GM comes with an optional sliding mount for SME boards. I've been very happy with my 12" GM on the 401 + massive RC plinth, and I know I could simply fit that to a 12" armboard, but I'd like to keep a smaller footprint this time, (and keep the 12" on the Garrard) so am thinking to mount a 10" arm on the smaller armboard. Schopper say that the smaller armboard will work with both 9" and 10" arms.

Audio creative offer two 10" arms, with slightly different Pivot to Spindle lengths. One is 240mm P2S and the other 254mm P2S. (Their 9" arm is 229mm P2S.)

It's my understanding that as a general rule of thumb it's better to fit the longest possible arm in any given circumstance, so could anyone more clued-up than me (e.g. almost anyone) advise me what's the longest arm I could go for in this case? Is there an ideal arm length for a TD124 deck? Or is it just horses for courses?

I know from online research people have fitted the FR-64s with success, and that's 245mm effective length. Is 254mm going to be pushing it too far?

[Barry]

If you want the base of the pickup arm to be within the chassis of the TD124, then 10" is the maximum practical length. You might, with difficulty, be able to mount a 10.5" arm but the arm pillar will be very close to the rear right hand corner of the chassis, and if the arm pillar is of a substsantial diameter then it will interfere with the chassis.

All you need to do is to measure the distance from the arm spindle to a point either 240mm or 254mm away to see if they comfortably lie within the TT chassis, such that you can use the smaller armboard.

[Ammonite Audio]

You can just about fit an FR-64S with 230mm spindle-pivot mounting distance to the TD-124 with a standard armboard, but any more than that will be difficult and perhaps impossible to accommodate because you end up with the arm structure wanting to be positioned further out than the edge of the metal chassis will permit. So, you need to forget about 10" arms - that's too much for a standard armboard and not enough for an 'outrigger' board, so a totally unworkable proposition. The 9" GrooveMaster II with 229mm P/S distance would be fine, as you have already noted; also the 9" GrooveMaster II-J which follows Jelco geometry with 214mm P/S distance would be fine. I'm currently running the s-shaped variant of the 9" GrooveMaster II-J and it's a magnificent sounding and IMO very smart looking thing - it would work very nicely indeed on the TD-124.

https://ammonite-audio.co.uk/wp-content/uploads/2020/09/GrooveMaster-9JS-SL1200_SPU_WoodA-1-600x450.jpg

[nickbaba]

Thank you gents - that's very helpful indeed.

So: forget the 10" idea - go 9" (or 12" on an outrigger board, or large plinth.)

Hugo - good to hear that the 9" S-shaped GMII gets a thumbs-up from you. I have a Jelco 750 on my old Technics so may also try that, if I decide to go with a 9" arm.

[Ammonite Audio]

Thank you gents - that's very helpful indeed.

So: forget the 10" idea - go 9" (or 12" on an outrigger board, or large plinth.)

Hugo - good to hear that the 9" S-shaped GMII gets a thumbs-up from you. I have a Jelco 750 on my old Technics so may also try that, if I decide to go with a 9" arm.

If you do, then replacing the Jelco later on with a 9” GM II-J is a simple matter of swapping collars and arms. The GM is in quite another musical league, compared to any Jelco, including the late and much missed knife-edge models.

[ballafish]

Hello, I made my own board on my TD 124 for my SAEC 308 arm, 240mm around 9.4" and it fit but I don't think I could of gone much longer. I would post a picture but could not figure out how to attach. I do love this setup.

Allen

[Ammonite Audio]

Hello, I made my own board on my TD 124 for my SAEC 308 arm, 240mm around 9.4" and it fit but I don't think I could of gone much longer. I would post a picture but could not figure out how to attach. I do love this setup.

Allen

According to Vinyl Engine, the SAEC has effective length of 240mm, but spindle-pivot mounting distance of 235mm, which is why you were able to just about fit it on the TD-124. Lovely arm - Noriyuki Miyajima uses the slightly longer SAEC WE-308L in his reference system, and that is quite some recommendation.

[Barry]

I have just measured the available arm pivot to spigot distance on my TD124, and depending on the diameter of the arm pillar, 240mm is the maximum length that can be accomodated. It will be tight but not impossible.

[nickbaba]

Thanks all for the input - I am going with the 9" Groovemaster II.