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stevenjh
12-05-2005, 08:44 PM
I recently purchase the Music Hall mmf-7 turntable. Unpackaged the unit and did the setup per the instruction manual and all seemed well. Played a few albums and it sounds really good compared to what I had before.

What I noticed is that when the platter is spinning, there is a rubbing or friction sound that happens in time with the rotation. The sound occurs if I remove the platter and just spin the sub platter manually. I'm thinking this rubbing or friction can only result in degraded performance.

I have pulled the subplatter out and it appears fine to the naked eye. There is a shaft from the center of the subplatter that goes into the center of the turntable. It seems to me that this shaft must be rubbing on the insert it slips into. I suppose that some rubbing would have to occur with the rotating shaft. What I'm concerned about is the rubbing/friction sound. Is that normal?

Does anyone have any ideas what the problem might be? Maybe just need some lubrication? Bent, off-center, or off-axis subplatter shaft?

Any help appreciated.

Thanks, Steve

royphil345
12-05-2005, 11:50 PM
I can't imagine a center bearing making much noise. If it does, it's defective, send it back. Is the motor pulley located underneath the sub-platter? If so, it may be mounted too high on the motor shaft, causing it to rub against the sub-platter?

I just looked to see what a MMF-7 was... Guess the motor pully is not located under the sub-platter. Higher-end table than I thought. You shouldn't be able to hear any bearing noise at all at normal speeds. I would just send it back to whomever I bought it from. Even if some lube quiets it now, I'd be very worried about the future of an expensive part on an expensive table.

BRANDONH
12-06-2005, 07:15 AM
I recently purchase the Music Hall mmf-7 turntable. Unpackaged the unit and did the setup per the instruction manual and all seemed well. Played a few albums and it sounds really good compared to what I had before.

What I noticed is that when the platter is spinning, there is a rubbing or friction sound that happens in time with the rotation. The sound occurs if I remove the platter and just spin the sub platter manually. I'm thinking this rubbing or friction can only result in degraded performance.

I have pulled the subplatter out and it appears fine to the naked eye. There is a shaft from the center of the subplatter that goes into the center of the turntable. It seems to me that this shaft must be rubbing on the insert it slips into. I suppose that some rubbing would have to occur with the rotating shaft. What I'm concerned about is the rubbing/friction sound. Is that normal?

Does anyone have any ideas what the problem might be? Maybe just need some lubrication? Bent, off-center, or off-axis subplatter shaft?

Any help appreciated.

Thanks, Steve

Is the shaft made of stainless steel and the insert a made of bronze?
When I first got my Pro-ject 1.2 (I no longer use) it did the same thing and I could hear the sound through the system at higher volumes.
I used a .22 cal gun hone with a little gun oil and carfully de-burred the insert then cleaned the insert out with a q-tip and alcohol.
The burr in the insert actually caused a tiny gouge in the shaft so I just used steel wool to de-burr the shaft and cleanded the shaft with alcohol then re lubricated with the gun oil.
The friction rubbing sound went away.
I would then at least once a month clean out the insert with a q-tip & alcohol clean the shaft and re-lube.
Or like royphil345 said, take it back.And if you do I would make then test the bearing there

stevenjh
12-06-2005, 09:33 AM
Here is a response from Music Hall:
Hi,

It`s not serious.

Try leaving it running for a day or 2. If that doesn`t work, I can send you a bearing thrust plate (The large nut on the bottom of the bearing) and that will solve the problem.

Roy Hall


Any thoughts?

BRANDONH
12-06-2005, 10:13 AM
Here is a response from Music Hall:
Hi,

It`s not serious.

Try leaving it running for a day or 2. If that doesn`t work, I can send you a bearing thrust plate (The large nut on the bottom of the bearing) and that will solve the problem.

Roy Hall


Any thoughts?
I guess the best thing is to try their recommendation and it my work but it may also scar the shaft as it did mine.
On my thrust plate (insert) the rubbing sound did not go away until I de-burred it my self.

royphil345
12-06-2005, 11:05 AM
This is like a $1000.00 turntable???!!! The manufacturer knows what's wrong without looking at it???!!! Send it back!!! There's got to be a better way to spend $1000.00!!!

BRANDONH
12-06-2005, 11:37 AM
This is like a $1000.00 turntable???!!! The manufacturer knows what's wrong without looking at it???!!! Send it back!!! There's got to be a better way to spend $1000.00!!!
I agree.
And then get one of these

http://www.electronics-expo.com/images/large/500/TECSL1210M5G_CENTER.jpg
http://www.electronics-expo.com/images/large/500/TECSL1210M5G_LEFT.jpg

Install a good cartridge and use the rest of the money for albums.
Technics SL-1210M5G (http://www.panasonic.com/consumer_electronics/technics_dj/prod_intro_sl1210m5g.asp)

$488.88 + shipping (http://www.electronics-expo.com/product.jsp?x=SL1210M5G&webcategory=null&submenu=null)

JohnMichael
12-06-2005, 11:41 AM
If you can take it back take it back! I would also try contacting the Project co. where the turntable was made to see if they have heard from others about bearing problems. After all the main bearing and the tonearm bearings can seriously affect sound quality. If it is under warranty I would not do the repair myself. If you change the thrust plate yourself will you void the warranty. You deserve better for the money you paid.