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 Post subject: Re: Rumble filter ideas, anyone?
PostPosted: Nov Mon 19, 2018 4:23 am 
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I finally had some time to get back to this.

The tt sits on a storage shelf, and the speakers were next to it on a different storage shelf---moved the speakers to the floor, far away from the tt--no difference.

I thought about relubricating the motor, so I took the bottom cover off---that's a no-go. In order to do it, I'd have to remove the motor--unfortunately, the motor is connected with one of those dreaded ribbon cables where the bare ends go into a clamp of sorts. I've never had luck getting those back together, so I left it.

But in getting a closer look at the rubber feet, I noticed something on all four--glue residue. There was something attached to these feet that is no longer there, and I don't know if it would have an effect on damping, because I don't know what it was


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 Post subject: Re: Rumble filter ideas, anyone?
PostPosted: Nov Mon 19, 2018 4:33 am 
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what Dave said, change the feet also. That can definietely cause rumble.


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 Post subject: Re: Rumble filter ideas, anyone?
PostPosted: Nov Mon 19, 2018 4:54 am 
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I'm on ebay right now, looking at new feet. The problem is going to be finding ones that are heavy duty enough---this beast weighs almost 13 lbs, while many other tt's weigh much less

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 Post subject: Re: Rumble filter ideas, anyone?
PostPosted: Nov Mon 19, 2018 5:21 am 
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Ok, I just bought some feet on ebay. They're from a Technics, but in doing research, that tt weighs 14 lbs---close enough to 12.6 lbs for me

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 Post subject: Re: Rumble filter ideas, anyone?
PostPosted: Nov Mon 19, 2018 3:30 pm 
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tubes4life wrote:
There was something attached to these feet that is no longer there, and I don't know if it would have an effect on damping, because I don't know what it was


As I said before, probably felt rings. Those being absent could be a cause of rumble, but much less likely than hardened rubber. The felt is mostly there to protect the surface of whatever the TT sits on (i.e., nice furniture).

From your pic, it doesn't seem the foot is collapsed to the point that the plate/mounting portion is touching the shelf. If this is the case, and the other feet are the same, and the rubber is still nice 'n pliable, I would be surprised if they are the cause of your rumble. Of course, that pic is with no weight bearing on the foot. If the turntable weight causes the plate/mounting portion to rest on the shelf, then yes, it can be a source of rumble.
Good luck with the replacement feet.


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 Post subject: Re: Rumble filter ideas, anyone?
PostPosted: Nov Mon 19, 2018 6:23 pm 
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Thanks, I hope they work. With the weight of the tt on the feet, they are indeed crushed against the bottom cover with no play at all

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 Post subject: Re: Rumble filter ideas, anyone?
PostPosted: Nov Sun 25, 2018 12:03 am 
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Ok, the new feet are on---they made a big difference! But the problem is still not gone on all records, and I think I may have figured out why--the platter mat appears to be warped, thus making any slightly warped LP's I play on it seem even more so (at least the first couple of tracks). I have no problem at all with 45's.

So I guess a new platter mat?

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 Post subject: Re: Rumble filter ideas, anyone?
PostPosted: Nov Sun 25, 2018 3:39 am 
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t4l,

Please post pic of this unit.


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 Post subject: Re: Rumble filter ideas, anyone?
PostPosted: Nov Sun 25, 2018 5:14 am 
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I hope this helps, not sure what you're looking for


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 Post subject: Re: Rumble filter ideas, anyone?
PostPosted: Nov Sun 25, 2018 5:17 am 
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It couldn't hurt to try replacing the mat, but I think if you aren't having any rumble issue at 45, you shouldn't be noticing it at 33 with the same mat, if the mat were the problem.
Badly warped LP's (and/or mats) can cause mistracking/skipping/leaping of the stylus, but rumble.. hmmm; damaged or dirty grooves yes, but warpage.. not impossible but less likely.

Might there be some kind of platter oscillation occurring at the slower speed? You said the strobe is steady, but I wonder whether the DD control is stuttering subtly and you just don't see it.

Anyway, it won't cost you much to find out. You can cut a new mat from a roll of grip pad or use cork or leather, etc.
I used the grip liner material on the last TT that had a disintegrating anti-static foam mat. While it isn't billed as "anti-static", there was no noticeable static buildup upon lifting the LP.

I used 2 layers of this product on the TT above, which equaled the thickness of the original mat: https://contactbrand.com/products/beade ... 7721542750

Layer up until you get to the desired thickness. It's cheap and you'll probably find other uses for it, even if it doesn't fix your TT issue.

Or, use a single layer of thicker material.


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 Post subject: Re: Rumble filter ideas, anyone?
PostPosted: Nov Sun 25, 2018 5:56 am 
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Scuz me, but isn't your mat on upside down?


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 Post subject: Re: Rumble filter ideas, anyone?
PostPosted: Nov Sun 25, 2018 9:06 am 
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Thanks for the input, guys.

Johnny, the owners manual says no---they talk about aligning the cartridge overhang with the center groove of the platter mat, which is not on the other side.

I'll be honest, I'm about ready to throw in the towel on this one. If it has mechanical issues, there's nothing I can do about that. But I can buy another tt on ebay for $100 or less, and this time I might go for belt drive. A new belt cost $20, no biggie.

I do truly appreciate all of the help that's been given, you brought up ideas that I'd never even thought about.

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 Post subject: Re: Rumble filter ideas, anyone?
PostPosted: Nov Sun 25, 2018 2:39 pm 
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tubes4life wrote:
Thanks for the input, guys.

Johnny, the owners manual says no---they talk about aligning the cartridge overhang with the center groove of the platter mat, which is not on the other side.

I'll be honest, I'm about ready to throw in the towel on this one. If it has mechanical issues, there's nothing I can do about that. But I can buy another tt on ebay for $100 or less, and this time I might go for belt drive. A new belt cost $20, no biggie.

I do truly appreciate all of the help that's been given, you brought up ideas that I'd never even thought about.


that might be best. I was beginning to lean toward bearing issues with the motor. The picture helped.


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 Post subject: Re: Rumble filter ideas, anyone?
PostPosted: Dec Sat 08, 2018 2:17 am 
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Don't discount the comment on Grado cartridges having issues with some arms. Put a different cartridge in it before blaming the table.


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 Post subject: Re: Rumble filter ideas, anyone?
PostPosted: Dec Sat 08, 2018 8:11 am 
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Conrad Hoffman wrote:
Don't discount the comment on Grado cartridges having issues with some arms. Put a different cartridge in it before blaming the table.


I still have the old A/T it came with, I suppose I can give it a go and see if it makes a difference

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 Post subject: Re: Rumble filter ideas, anyone?
PostPosted: Dec Sat 08, 2018 2:18 pm 
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tubes4life wrote:
Johnny, the owners manual says no---they talk about aligning the cartridge overhang with the center groove of the platter mat, which is not on the other side.
I agree with Johnnysan that you may have the turntable mat upside down. I don't see a center "groove". There are 6 wide, indented bands. Which one are you calling the center groove?

I looked at Google images for this model and found what the other side of the mat looks like. There were pictures showing it placed both ways. But I believe the "center groove" is the circle seen near the center of the mat in this picture. But, all things considered, it probably won't make much difference as far as rumble is concerned.

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