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Upgrade for users of 1/2" mylar belt

This thread will be of interest to Galibier, Redpoint and Teres belt drive TT owners, or anyone using or thinking of using a drive belt made from 1/2" mylar. The belt material of choice on these tables for several years has been the silver holographic mylar streamers from sources linked on the Teres and Galibier websites. This outperforms everything else we've tried but like anything it's not perfect - and we've now found something better.

One of the silver holographic mylar's assets can also become a liability. That metallic layer, when new, gives the belt exceptional "grip" on the platter and motor capstan. Minimal slippage on transients is one reason the material works so well. Unfortunately, that layer can wear over time, leaving a silvery gray residue and allowing performance to deteriorate. The only solution has been a good cleaning and a new belt. No big deal, but if there was a better or more stable belt Paul and I wanted to find it.

I'll spare you a recounting of our many experiments and jump to the good news: thanks to (yet another) brainstorm by my resident genius/partner, we've developed a belt that both performs better and lasts longer. I've held off posting until we were sure, but after 4 months of steady use Paul’s idea is still working perfectly. The only negative is that making this new belt takes an hour or more of work spread over two days, but to us it's worth the effort.

HOW TO MAKE ONE

1. Cut a length of the silver holographic mylar tape sufficient for your TT, plus 3-4" extra.

2. Remove the silver metallic coating off the backside of the mylar. Paul used an acid etching cream popular with stained glass hobbyists to dissolve the metal - safe, quick and easy (use skin and eye protection).

3. Rinse thoroughly under running water, inspect to make sure you got all the silver off, wipe and hang to dry overnight.

4. Splice as normal to make a TT belt, making sure you tape on the OUTSIDE (which will be smoother than the now bare inside).

5. As always, the best splicing technique is to overlap the ends and cut on a 30-40 degree angle. Apply 1” video splicing tape (*not* tabs) across the belt at the *same* angle and trim away the excess.


WHY IT PERFORMS BETTER

Unlike any plain mylar ribbon you could easily buy, the silver holographic streamer has an ultra fine texture embossed on the back side of the *mylar* during manufacturing (*before* the metallic backing is applied). Once the silver layer is applied you can't see this texture, but that's what diffracts light like a million tiny prisms to produce the shimmery rainbow effect. Stripping the metal backing away exposes this texture, which becomes the contact surface of your new belt.

Paul realized this texture must exist and then hypothesized that using it for the working side of a TT belt might provide more “grip” on the platter rim and motor capstan than either plain mylar (which is extremely smooth) or the metallic backing. He was right. This belt produces more lifelike dynamics, both macro- and micro-, than even a brand new silver holographic belt - which heretofore was the best.

WHY IT LASTS LONGER

Removing the metallic backing exposes bare mylar, which is much sturdier than that fine layer of metal. Under normal use and assuming no accidents, one of these belts should last many, many months, perhaps years, while delivering consistent performance. Ours is going into its fifth month with few visible and no audible signs of wear.

Different motor capstan materials might interact with this belt differently, but I urge anyone with a compatible table to give this a try. Like all our favorite little tweaks, we'd find it hard to go back.

A FEW TIPS

1. Clean any silver/grey residue from your old belt off the motor capstan and platter before mounting the new belt.

2. As many of us have learned, the more inelastic the belt, the more critical motor leveling becomes. That is truer than ever with this new belt. Getting the motor set just right is touchy. Take care that your new belt is riding level in the center of the capstan before you start to play. You don't want it sliding up or down and mangling itself.

3. Motor distancing is also more critical than ever. Since this belt will not slip *or* stretch, tension must be perfect. The right amount is just shy of the tension that would tilt the motor off its feet.

4. Depending on your climate, the belt can build up static potential during use. Not enough to spark, but more than enough to attract airborne dust. I dust the belt's inside with my CF brush after each side before stopping the platter.

5. With this or any belt, always start your platter spinning with a helping push. Just pressing the motor's ON button creates lots of belt-wearing friction as the rapidly spinning motor tries to drag that heavy platter up to speed.

It all sounds like a pain, and it is! But the sonic and longevity results are worth the effort.

Cheers,
Doug
dougdeacon
dan_ed
2,451 posts
 
How can you go wrong with a name like BigCrank! ;-) So far I've stayed with the jump start type battery packs that can be found at various places. I don't have an external charger and these come with one built in.

So, there is another item for the list for next time I get down your way. The Anvil, and my Jump n' Charge. Sounds like a game for kindergardeners compared with BigCrank!
dougdeacon OP
3,338 posts
 
Dan,
We tried our big car recharger (similar to what Thom supplied you?). It sounded rougher than the Big Crank. I remember Thom theorizing that a Teres motor controller would respond more than a Galibier would to battery differences, due to its higher impedance. Paul says the Big Crank has very low internal impedance, so I guess that makes sense - as much as anything electrical makes sense! <;~)

Ducatrider,
I don't know any sources for 1/4" mylar. You could try what Chris Brady did when he first wanted to experiment with 2 mil vs. 1 mil mylar. He couldn't find 2 mil in 1/2" rolls, so he bought a large sheet and cut 1/2" strips with a straightedge.
livemusic
16 posts
 
Doug, thanks a lot for sharing your worthwhile experience!
I've tried it on my TT with huge success. Your belt replaced McCormic's black mylar tape and profound improvement accross the board was a revelation for me: my playback became better in each and every aspect. That was very educative experience indeed; now I convinced the interaction between platter, belt and motor is critical.
Next thing I want to try is battery power. I have earlier Teres Signature II motor (short case) with no battery power option. Can you recommend any battery/charger combination I can hook up without messing with electronics (my weakest point)? Thanks again.
dougdeacon OP
3,338 posts
 
Hi Livemusic,

Thanks for sharing your results, and glad you were able to hear the profound (indeed) differences that result from optimizing the motor-platter coupling. It's obvious when you think about it, but hearing is believing.

Of course the best implementation for any particular rig can be anything but obvious. It took us 5 years of trial and error with 10-15 belts to reach this point with this table. Some other table might need something different, though the principles are the same: no elasticity and minimal slippage.

For battery power you'll probably want the battery option from Teres. It should still be available, ask Chris. This provides the proper interface to the motor controller (internal to your Sig II) as well as a trickle charger. You could probably DIY if you had electrical skills, but I don't and apparently neither do you! Maybe someone who understands electricity will chime in with an easy DIY.

One tip: although the Teres charger disconnects itself when the motor's running, we still hear a small degradation in sound quality. A few others (not many) have reported the same. We have our charger plugged into an outlet strip with a power switch, which we turn OFF while we're listening.

For the best battery we've found (out of 5 or 6 tried), see the link I posted above.
jfd01
32 posts
 
Well I finally opened last night my new bottle of Etchall to remove the silver layer of my mylar belt (Galibier Serac), following the procedure outlined above by Doug--except that I was working with an already-made belt. I then did several listening passes, with different LPs, alternating the "cleaned-up" belt and a brand new one with its silver layer still in place.

Here is the list of the recordings I used for comparison:
- Vivaldi, Four Seasons, Fall, 1st mvt, Kuijken and La Petite Bande
- Beethoven, String quartet op.127, 1st mvt, Quartetto Italiano
- Stravinsky, Firebird, Infernal Dance of all Kastchei's subjects, Dorati/London Symphony
- Mahler, Symphony n.7, beginning 1st mvt, Haiting/Concertgebouw

So, a good range of ensembles and recording difficulties. In all cases, most noticeable were:
more extension in high register; much tighter bass, with better pitch definition and spatial localization; better sense of perspective in depth; slight recess of mid-bass range, giving a somewhat better separation between instruments (this one threw me off at first because it sounded like less body; but after some time I realized what was being gained rather than lost).

This has got to be one of the most spectacular tweaks I've experienced recently!
Thanks Doug and Paul, for your pioneering efforts!
Cheers.
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