What to do with a TT2?

[surayne]

How annoying that I've got an RB301 staring me in the face and yet I can't use it! I'm very, very tempted by the Jelco 750D though. I'm going to have a bit of a hunt behind the sofa and see if any spare pennies come up... if anyone knows of one going please let me know!

Coming back to the TT2 itself, someone mentioned running it with the base board removed to reduce resonance - any truth in this? Also, the lack of adjustable feet is a pain... would a plinth of some sort with adjustable feet make sense?

Looking at some of the discussions on the LP12, there seems to be some sort of black art involved in adjusting the suspension for optimum sound. I may have, perhaps, slightly adjusted one of the springs while trying to level the subchassis (it was in the manual, I swear!). If I check that the marks on the springs line up with the ones on the subchassis, it should be fine, I hope? How exactly am I meant to do this, since the springs are at the bottom and the nuts are on top?

[sq225917]

No black art with the TT2. The springs don't wind up quite like they do on the LP12 and the mass is better centred. Press down rough where the centre of gravity is, if it bounces cleanly up and down with a low frequency, between 5-10 cycles a second you have it spot on.

Removing the bass board will help dissipate motor noise.

[surayne]

No black art with the TT2. The springs don't wind up quite like they do on the LP12 and the mass is better centred. Press down rough where the centre of gravity is, if it bounces cleanly up and down with a low frequency, between 5-10 cycles a second you have it spot on.

Removing the bass board will help dissipate motor noise.

Thanks. There's a lot to like about this TT.

[shane]

If you have a look at this, it will show you the correct orientation of the springs if the red triangles have dropped off the chassis. Be a bit careful if you need to rotate the springs, the rubber spring seats are among the few parts which are pretty nearly impossible to replace. Incidentally, the alignment was the same for both types of chassis. Once you've got that right, adjust for level by turning the bolts with an allen key from above. The springs will not rotate as you turn the bolts unless the bolts and nuts are seriously rusty.



The next picture shows the best way to dress the arm cable, by running it forward to the P-clip under the arm-board securing nut, then back to the P-clip next to the cable exit on the back of the plinth. Remember that on the alloy-chassis version, only one arm-board stud should have a nut on it. The p-clips should be pulled up good and tight, and the nut tightened down.



If the springs are correctly oriented and the cable is dressed to minimise interferance with the suspension, then a finger placed on the platter halfway between the spindle and the arm base should induce a vertical bounce with no rotational component. If then the arm-board is level with the edge of the plinth, then you've got it spot-on.

These picture are of one of the very early TT2s which had threaded inserts for adjustable feet, the feet themselves being M6 bolts with plastic covers. This turned out to be a surprisingly bad idea, destroying focus and pace. They were very quickly replaced by rubber feet screwed down with self-tappers. You can see one reason why if you look at what's happened to the piece of wood across the back of the motor cutout. The rubber foot we replaced the rear screw foot with was mounted to one side of the cutout.

Because the plinth of the TT2 is filled with chipboard and has no large resonant cavity, I would be surprised if removing the base-board made much difference. Suck it and see, and then report back!

One of my main aims for the TT2 was to get rid of the mumbo-jumbo and hocus-pocus surrounding the suspension setup of the LP12. All it took was three M6 bolts, 19mm of MDF and a bit of lateral thinking.

There was an article that did the rounds in the eighties and nineties which wittered on about engineers coming out of university and turning left to go to Linn or right to go to Heybrook. It always made me laugh. Heybrook when I started employed four people, rising to ten when I left, only one of whom had any engineering qualifications, and none had been anywhere near a university. The TT2 was the product of several years of fooling around with bits of old turntables in my bedroom, which I never expected to go into production. When Peter and Stuart suggested it might be a worth doing, we went to a local engineering shop who looked at the basic parts, suggested ways of modifying them for series production and took on the task of providing us with the sub-platter, bearing and (steel) chassis. We found a casting company who could provide them with the raw castings to machine up the platters (and later the cast chassis), got Greaves of Sheffield to build the plinth, bought in lids and felt mats from Linn (who were very encouraging), and there it was. Not bad for a bunch of amateurs, but if anyone out there thinks they can see a way to improve it, give it a try and see if it works. I'd be really interested to know!

[AlfaGTV]

Great writeup Shane! This info is greatly appreciated and the knowhow will be put to good use!
Have spent my evening mounting the Audio Origami RB-250 on the older TT2, using a Bens Micro Glider L2. It replaced an Origin Live Silver MkIII and it's a little early to share any impressions, but it sure does sound nice!
The AO cables were easier to dress also as they are less cumbersome!

Wil try and make a proper comparison by switching the armboard between the two later!

Thx!
/Mike

[surayne]

Many thanks, Shane - this is really useful information. I may have some time off to play later this week, I'll let you know my thoughts. The only issue is that going to the K9 from the DL-160 is a bit of a shock, I need to sort the tonearm / cart side of things soon!

[DSJR]

The K9 used to be better, back when they were new...................

[AlfaGTV]

Very pleased!



Sounds beautiful!

[shane]

Looks good too!

[Macca]

Was there ever a TT1?