Belt drives are a tough call. If you have increased coupling between the belt, drive pulley and platter, you have greater speed stability due to less slippage. At the same time, increased coupling / reduced slippage also results in greater transmission of vibration from the motor / drive pulley and the platter. Obviously, one has to draw the line somewhere. Personally, i would rather have consistent speed and design the table to properly deal with both internal and external vibrations. Sean
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It seems like Teres is following in the footsteps of Redpoint. |
Sean, nice statement of the dilemma. It's one of those core conflicts that prevent "perfect" LP playback. Another such is the two contradictory demands on the tonearm. It is expected to hold the cartridge motionless above the groove, resisting all vibration induced by the stylus and cantilever, while at the same time following their lead to track a spiralling target. The better the arm is at one task the worse it must be at the other, at least conceptually.
Due to a number of design elements, the Teres 265 is highly resistant to vibration, including motor vibration. Therefore, as you say, closer coupling to the motor should stabilize speed by reducing stylus-induced variations. That was our experience. On other tables, YMMV of course.
Cmk, since Redpoint began by following in the footsteps of Teres, maybe they're both walking in circles! Of course going in circles is the goal, so I guess that's okay. :) |
Sean, With a precision DC motor cogging and vibration are
almost non-existent so rigid coupling of the motor and
platter tends to deliver the best results. In general I
have found that less compliant materials sound better.
However, there is a small contingent of Teres owners that
prefer the sound of rubber belts on their Teres tables.
Exactly the opposite of my experience. I don't know why
this is the case. But I suspect that it has to do with
personal tastes and system interactions.
Use of magnetic tape as a drive belt predates both Teres
and Redpoint. However, the guys at Redpoint are the ones
that pioneered the use of 1/2" wide VHS tape. It turns out
that they were dead on about the virtues of wide tape.
I am in the process of evaluating a number of new belt
materials and still have not pinned down what type of
belt will be the standard Teres issue. The mag tape and
silk sent out with the 265 models is a interim until the
evaluation is done. Right now 1/2" wide decorative mylar
is what I like best. Better sounding and less fragile than
VHS tape.
Chris |
Hello Gang. An interesting thread that caught my eye.I should qualify that I have no experience with either the teres or redpoint tables.I have the original Melco table with a 70 pound brass plater and outboard motor.Quite a few years ago... I did experiment with various coupling materials and kept my notes.I experimented with a round rubber belt,a flat rubber belt,silk thread,dental floss,cassette tape,and 1/4" magnetic tape from a reel to reel.In my case the 1/4" tape was the clear winner, the dental floss a close second.The only liabilty or drawback with using the 1/4" inch magnetic tape is that it does not last very long,typically- about 20 hours before it separates or starts to shred or crimp.Once it seperates it cannot be re-used.I made up a bunch of them for backup. Try the dental floss...far quieter than both rubber or silk and does indeed capture more of the micro dynamics off the record and lasts for a long time.Your motor spindle size and shape will obviously dictate the size of tape one can accomodate.The cassette tape was nothing but a pain in the butt as it would typically shed itself within 4 to 5 hours of playing time. Your mileage may vary of course.Hopefully.. others have tried different materials and will respond to the thread.Cheers. |
I have been using the 1/2" mag tape drive on my Redpoint and it seems to be pretty much trouble free (4 months and still on the original belt) and sounds very good. I have not done a direct comparison with other materials but would be interested in trying out the decorative mylar for a comparison. Does anyone know where you can get this in small quantities? |
Hello Chris. What is this decorative mylar stuff? and where can it be found. Thanks |
I also found the non-stretch materials to be best in my system. I actually went to using Spectra fishing line, which is totally non-stretch and even used in bulletproof vests. It sounded better than the silk, and fit my pulley which was designed for the silk cord. It was a bitch to tension because of the total lack of any stretch, but once it was tensioned it stayed perfect. However, it was a little rough on the aluminum pulley, and it started to wear a groove in it. I am not in the camp that prefers the rubber belts.
I am very interested in trying the tape drive, and have already contacted Chris about a change-over on my table. I am looking forward to this with great anticipation. |
You can get the decorative maylar tape at:
http://www.mccormicksnet.com/mccormicks/tapes.htm
Scroll down to the bottom of the page and look for
Mylar Streamers". Availabile in a variety of bright
colors for the adventursome and also plain old black.
$4.10 for a 100' roll.
Chris |
WARNING TO ALL
Cut power to your Teres motor before attempting to feed the tape. Once the tape is on the pulley, even part way, any movement of the platter will start the motor and there goes your tape. Voice of experience :(
RANDOM THOUGHTS
If 1/2" tape is good, would 3/4" or 1" tape be even better?
Does wider tape put more pressure on the motor bearings?
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A wider tape or drive material should:
1) spread out the vibrational load introduced to the platter that originated with the motor in a more consistent manner
2) help to damp air or platter-borne vibrations due to the increased contact area of the tape with platter
3) offer a greater contact area for improved power transfer with less slippage
4) cause less "walking" of the spindle within the shaft resulting in greater pitch stability
5) reduce eratic bearing wear
Sounds like a "win/win" situation in "theory".
How does one go about sizing the tape / mylar and attaching it to itself once cut to size ? Sean
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Sean, sounds like I should get some 70mm film stock and a really tall pulley!
My tape was spliced just like the leader on a VHS tape would be. |
I picked up a TAC 1/2" video tape splicer from B&G Sales in Canada. It was around $50 and does an excellent job splicing. I would think it would be hard to get the tape lined up correctly without a splicer. |
Here's another source for a 1/2" videotape splicer:
http://www.mvipro.com/splicingblock.html
$32.95US for a splicing block and some splicing tabs. |
Thought I would give you some of my observations on the mylar tape. I have been using a 1/2" mag tape shiny out on a Redpoint/Galibier battery powered moter controller and Testa Rosa TT with drilled aluminum platter, teflon top, and anvil weight. I ordered several colors of the mylar tape from the source that Chris suggested. I ordered the silver, gold, and holographic and felt if the tape sounded better than my mag tape then I would have a color selection to choose from. I noticed that the holographic was much thicker and stiffer than the silver and gold. First I tried the silver and compared with my 1/2" mag tape. I have been running the mag tape shiny side out. After listening to about 5 changeovers on familiar music I came to the conclusion that images were much better focused with much tighter bass and more detail. I pretty much heard the differences that Dougdeacon heard going from silk thread to mag tape. It is possible that mag tape shiny in could sound close to the silver but the mylar tape looks alot better than mag tape dull side out. Next I tried the holographic mylar and compared with the silver. Believe it or not I saw the same type improvements that I had seen going from mag tape to silver. It seemed better yet with further improvements in image focus and clarity. I think the differences have something to do with the finish as well as the thickness of the tapes. I took my caliper to them and the mag tape I was using was .001 thick while the silver mylar was .0015 and holographic was .0025. The only problem I had with the holographic was that my splicing machine had trouble getting a real even splice. I think this was due to the thickness of the tape. It took several tries before I could come up with an acceptable splice. Overall IMHO the holographic mylar seems like a winner. The side benefit is that it looks very cool spinning around my polished aluminum platter with colors changing with various angles. I would like to hear from others that may have tried the mylar tapes to get their impressions as well. |
Dmailer,
Thanks for the excellent followup. My mag tape is also .001", so I guess I'll have to order some of that mylar. I'll try to remember to post our impressions.
Unfortunately, one of our cats goes beserk for holographic silver gift ribbons. I'll have to avoid that color for the sake of my cartridge. |
To quote Teres "With a precision DC motor cogging and vibration are almost non-existent so rigid coupling of the motor and platter tends to deliver the best results".
Sounds like a case for direct drive. |
You're just jealous because you don't get to fiddle with belts and strings! :)
Wouldn't spinning a 30+ pound platter via DD require a larger, much higher torque motor? How would Teres maintain "almost non-existent levels of cogging and vibration" without driving costs up to the Walker level? |
Dougdeacon...In my time I did my share of fiddling with belts and strings, not to mention little rubber idler wheels(which preceeded belts). I guess it's your turn. Enjoy!
With regard to motor power, the weight of the platter has minimal impact on torque requirement, unless you are a disc jockey and want to get up to speed fast. Motor torque depends on bearing friction, which, for a suitable bearing, varies only slightly with loading. |
Eldartford... it's okay, I've always been a slow starter. There's not much DJ work for us classical lovers and a Teres isn't exactly portable anyway. I guess it might be if it were direct drive, one less box to lug around...
You certainly raise an interesting question. Almost makes me want to mod my TT for DD and report results. Now where did I put that chainsaw? |
Hi
I supplied a few Teres owners with our drive belts which we use on our Hydraulic Reference model turntable, they must have been impressed with the results as they bought another ten. |
