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In Reply to: RE: Speed accuracy on vintage belt drive TT with "electronic speed control" posted by JoshT on January 13, 2017 at 23:02:46
So, with the benefit of a good night's sleep, I tinkered ever so slightly with the pitch adjustment nob and am now at a stable average speed of 33.26, which is within 0.2%. It did take about 20 minutes to gradually climb from 33.16 to 33.26, but then it held firm for about another 20 minutes before I turned it off. I'll give it a few more whirls throughout the day to see if it consistently performs that way. And I'll try with a record on it too, which I guess would also verify if the speed control is working as it should.I will definitely clean the belt and applicable surfaces. And I'll also at least give the pitch adjustment nobs a full twist each way a few times to see of that has an impact. Seem like good ideas in any event, and might improve any wow and flutter? (Though I don't hear any.) As far as the internal electronic adjustments, I just don't dare try on my own, but will check with some friends to see if they'd be comfortable trying with me hovering to learn.
Finally, where would one purchase a belt these days that would safely be within spec and do no harm? Also seems like a good investment, even if only for the future.
Thanks again gentlemen, and I'll report later in the day whether I find any notable changes after performing the additional tasks!
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"If you are the owner of a new stereophonic system, this record will play with even more brilliant true-to-life fidelity. In short, you can purchase this record with no fear of its becoming obsolete in the future."
Edits: 01/14/17Follow Ups:
So, it held steady at 33.26 with a record on (plus the weight of the iPhone of course). The speed did not change when I put the tone arm down (I have a Shure M97x at 2g with brush down).
Just cleaned the belt and drive spindle and edges of the sub-platter - so all relevant surfaces - and it's now holding at 33.27. That was a great suggestion because the belt was kind of stuck to the edges of the sub-platter and everything was just a bit tacky to the touch. Probably more tar from the years of cigarette smoke. When I cleaned the power cord and interconnects for the first time a lot of brown gunk came off so It should have occurred to me to clean the belt. Thanks!
So, I'm proclaiming success with the average speed (knock on wood)!
I might test the wow and flutter in due course, and I'll get a couple spare belts for the future anyway.
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"If you are the owner of a new stereophonic system, this record will play with even more brilliant true-to-life fidelity. In short, you can purchase this record with no fear of its becoming obsolete in the future."
Take that stupid brush off your cartridge.
"If people don't want to come, nothing will stop them" - Sol Hurok
It seems like there is a split among people who have done both. Of course it would be easy enough for me to give it a try.
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"If you are the owner of a new stereophonic system, this record will play with even more brilliant true-to-life fidelity. In short, you can purchase this record with no fear of its becoming obsolete in the future."
I don't think there's anything good about it.
I noticed that you could hear the music before it played, like pre-echo. Not only through the speakers but you could hear it in a dead silent room from right off the record.
And, where is that dust going that it's "picking up"?
Nope, I learned my lesson with the Shure V15/Type V.
"If people don't want to come, nothing will stop them" - Sol Hurok
here is a whole page to look through.
I was more wondering if there are any dealers of choice or any to avoid. LPGear, who I have dealt with before and has a stellar reputation, sells them for $18.90 a pop. But the place called Vintage Electronics, also US-based, sells them for $8.00 each (and less if you buy 2 and even less if you buy more). The only other source I saw was a guy in Germany on eBay, who had even lower prices.
So, assuming the belts are either both original Philips or are both from the same aftermarket OEM source, I will go with Vintage Electronics for the far lower price, but neither site specifies whether they are actual NOS Philips belts or aftermarket. Should I assume the latter?
The only reason I'm at all nervous is that a repair guy once told me not to use aftermarket belts on a Thorens TD126 MKIII (another belt drive table with speed control) because he said they are all bad and burn out the motors.
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"If you are the owner of a new stereophonic system, this record will play with even more brilliant true-to-life fidelity. In short, you can purchase this record with no fear of its becoming obsolete in the future."
Josh: Probably aftermarket, I'd assume. But you probably needn't worry about that, as the AFxx7 family models aren't as sensitive in terms of belt quality as most other belt-drives because of the aforementioned DirectControl design.
I.e., on most of the other belt-drive designs with DC motor only the actual motor speed is sensed (if at all) and "processed" by the speed control circuitry, so that these designs have to rely on very good belt quality for a correct and constant transmission ratio as well as a comparatively heavy platter to provide a sufficient flywheel effect for low wow & flutter. Whereas the few belt-drive designs with actual platter speed sensing (first one as far as I'm aware was the Braun PS550, closely followed by Philips AFxx7 family (and its successors like for example the AF829(II)) and some years later the Dual CS750(-1)...) can compensate for somewhat lower belt quality to a certain degree and also don't necessarily require a comparatively heavy platter for good to very good wow & flutter performance (the DirectControl family models typically delivered ~ +/- 0.05 to 0.04 % (DIN, weighted) in magazine review measurements). Quite a clever concept - so that I'm actually pretty disappointed that manufacturers don't make more use of it in current models, especially as comparatively complex electronics would nowadays seem a lot cheaper and easier to implement than high precsion mechanics compared to the late 70s...
Greetings from Munich!
Manfred / lini
P.S.: Almost forgot: I'd guess for the speed adjustment using a strobe disc would be more convenient than using a smartphone with a suitable app.
I'll go for the Vintage Electronics - two for about $15.
I'm really enjoying reading up on this table.
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"If you are the owner of a new stereophonic system, this record will play with even more brilliant true-to-life fidelity. In short, you can purchase this record with no fear of its becoming obsolete in the future."
I bought a belt once from Turntable Basics for my Thorens TD-126 MkIII and it was twice as wide as the original. I wrote to Turntable Basics expecting them to exchange it, but instead the guy told me to take a razor blade and slit it down the middle so I would have two belts for the price of one. It sounded like he wasn't willing to exchange it or else he really didn't want to. Anyway, I built a little jig to keep the belt and razor blade in position as I dragged the belt through the jig and slit it down the middle. It actually worked very well and I ended up with two belts. Both of them worked just fine.
Good luck,
John Elison
Silver lining and all I guess. :-)
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"If you are the owner of a new stereophonic system, this record will play with even more brilliant true-to-life fidelity. In short, you can purchase this record with no fear of its becoming obsolete in the future."
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