One more additional bit of information. The multi-meter reads 18 volts at the motor's power adapter output.
Question: is there any kind of belt inside the motor that might be causing the problem (because it's dilated or something)?. It's definitely not the AC voltage.
Still desperate. |
It is indeed in the right groove, Eddaytona: the smaller one (and the larger one, as indicated, when I am using the Speed Box II).
And, Stefanl, thanks: I will try your trick. However, I am still not sure why it would spin faster: on the Billie Holiday LP "Songs For Distingué Lovers" (that I know very well), although the instruments may appear to be playing at the correct speed/pitch, Ms. Holiday's voice is almost unrecognizable, as if all the "low-toned hurt" in her voice was nowhere to be found. On Pat Metheny Group's LP "Offramp", it's like Metheny's guitar (or Lyle Mays' piano) is playing a third faster than what was recorded. And I am very familiar with these recordings, be it on tape, LP or CD. Very frustrating indeed!... |
Thanks, Al.
I have that reading when the power adapter is connected, but with the motor not running. I have the same with the mmf-7.1.
I don't get what's wrong; there must be a rational explanation (and a solution), I'm sure. |
Thanks for your input, guys. But, Stefanl, lubricant to the bearing? Where exactly? Please elaborate.
Mofimadness: there's really no need for a strobe disc. My ears (and a couple of others) have indeed verified the (much) increased speed.
Dweller: I am pretty certain it's not high voltage. I live in Commack, New York (115V) and the added Pro-Ject Speed Box II -- suggested by Roy Hall himself and a couple of audiophile friends as well -- should have corrected any (major and/or minor) speed 'discrepancy'. In addition, I am using a Music Hall belt (the original one and a new one, bought directly from Music Hall). My line preamp is an Audio Research SP16L and my phono preamp an EAR 834P (with Cardas Golden Cross 1.0-meter interconnects). It does happen to all LP's, ever since I went back to analog about 6 months ago (the mmf-7 was stored in the attic for about 2 years). Lastly, the motor is "in the hole" of the plinth, as indicated.
I really don't know what else to do, except maybe buy a new turnatable, preferably from another manufacturer (maybe Rega or VPI). Roy Hall just sent me a new motor: I'll try it as soon as I receive it and report back to this thread. |
I did try that already, Almarg; thank you. It does spin closer than what it should, but still not at the correct speed. Without the Speed Box II, it's definitely too fast.
I also tried the other AC adapter: same result.
I unfortunately do not have a multimeter to measure those parameters.
Thanks again. |
Thanks, Stefanl: I did read it in the manual. However, I am not sure what "main bearing" means. Where is it located: under (pardon my ignorance)? Please elaborate on the coating of the spindle.
As for warming up the system, it has been back out on top of my rack for more than 6 months now and I have played at leat 7 or 8 LP's so far, even with the atrocious (to my ears) speed problem, both with volume and mute.
I would appreciate any additional comments/advice (but I have yet to put electrical tape around the platter: it seems such a not so elegant trick). |
Thanks again, Stefanl. Now, I get it for sure (what I thought I understood is certain now). I will oil both the spindle and the main bearing with Mobil 1 (with teflon). I'll let you know what my results are. |
After oiling the main bearing and the spindle, no change whatsoever. I give up.
I am going to buy a new turntable from another brand. I don't have the slightest clue why this is going on.
Thanks all. |
I'll try but, to be honest, I am fed up with this turntable. Thanks. |
I just finished my testing with a multi-meter (I couldn't locate a variac) and found between 115.6 and 116.7 volts. Better yet, I used a 500W AC automatic voltage regulator (and plugged the motor in): no change. It still spins too fast, somewhere closer to 45 rpm than 33 1/3. I really don't know what else to do. And please note that I used 2 different Music Hall motors with exactly the same results and that the Speed Box II didn't/doesn't change a thing.
I am desperate now. |
As a matter of fact, I did: no change.
The small pulley is clean, the larger one too (as I have tried to correct that speed problem with a Pro-Ject Speed Box II).
I am expecting another motor from Music Hall, but at this rate, I doubt that will change a thing. We'll see... |
Dweller, I did some research on the web about variable voltage modifiers (variac) and found them to be a very interesting item and not pricey at all (I confess that I didn't know anything about them before). Would you care to recommend a particular one (preferably sold at The Home Depot/Lowe's or Sears or Radio Shack) that I could use in that kind of application to make sure that I have the correct constant voltage? In addition, would it be "crazy" to use it in combination with my voltage regulator?
Please advise. |
Well, I'll wait until I receive the new motor some time next week.
And, Dweller, I emailed (member) TVAD asking him to participate in the dialogue. Let's wait and see what he will bring to the discussion. Thanks. |
I jus tried my friend's mmf-7.1 in my system and it played beautifully: no speed problems whatsoever. I have offered him to buy it and he agreed (he is going back to Rega).
But, I still need to make the mmf-7 work: I'll give it to my older daughter (now a college student) who has a keen interest in audio (I guess the apple didn't fall far from the tree). |
Nope, not at all; he was very happy with his mmf-7.1: just the upgrade bug. I simply asked at the perfect time.
You seem not really happy with Music Hall turntables: may I know why? |
I am going to swap the motor, the belt, the sub-platter and the platter and see what happens. |
I swapped the motor and, surprise, surprise: it is now much slower, almost not turning at all. I am going to change the platter and the sub-platter now.
Did I say weird? |
I am currently away from home; I will resume all (measurements, swapping parts, etc.) upon my return next week. Thanks all. |
I am back with the conclusion: there isn't any.
Twad was right: the mmf-7 is a joke. With the new motor, it almost does not spin at all. I don't see any reason to use my time trying to understand what's wrong with this turntable. I'll be using the mmf-7.1 for the shortest time period possible and buy a VPI. Cheers all... |
No, I didn't. Thanks for letting me know. I will have to pass however. The VPI purchase will come some time in the second quarter of 2010 (at the latest), preferably a ScoutMaster. Thanks again... |
Finally, some closure: I have both turntables (mmf-7 and mmf-7.1) spinning correctly now. After a lot of tweaking, I finally put a little (toilet) paper on the small rod on top of the motor before easing the pulley, giving it a snug fit. Since then, no more speed problems. It even works perfectly with the Pro-Ject Speed Box II now. In fact, there was no adjustment screw (and no place to insert one) at the base of the motor pulley, thus making it going either too fast (or too slow): "élémentaire, mon cher Watson!" as the French would say... |
Actually, it was too fast at first (don't ask me how or why); then, lately, it almost wasn't turning at all: that's what called my attention on the rod and the pulley. I guess I somehow got lost into the measuring and the swapping of parts between the 2 units.
And, yes, I am so glad it's solved! I can now give the mmf-7 to my daughter (her birthday is in about 2 weeks), keep the mmf-7.1 and think about my VPI purchase while I listen to some fine LP's... |
Indeed, Tom.
And, thanks for the tip. Happy Thanksgiving!... |
