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 Post subject: I'm at it again
PostPosted: 20 May 2014, 21:28 
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Joined: 04 Jun 2008, 20:59
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Location: Arizona, USA
Hi Everyone, I'm fairly sure any of the avid diyers out there have a character flaw similar to mine. Nothing is ever quite good enough and the obligation to tinker is overwhelming. So I am now in the process of building a new plinth for my main turntable. It started life as a Dual 701. That was two plinths ago. The latest one performed exceptionally well at the recent Dallas audio show. Still not quite good enough (there I go again). The new one (will post photos in a few days of the construction progress) is slightly larger and thicker. The controls will be recessed on the top and everything else is concealed. It will use an Origin Live Alliance tone arm. I'm considering using black high gloss laminate for the top and sides. The plinth itself is already cut out and partly shaped . It uses Maple faced 5 ply plywood (19mm thick) for the top and bottom layers and a cross laminated 32mm thick pine layer in the middle. The arm is adjustable in all directions (vertical height, side to side tilt and front to back tilt). I have found that this is an important feature as most turntable / arm combinations are not parallel in all directions. More to follow.

Good listening
Bruce

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 Post subject: Re: I'm at it again
PostPosted: 20 May 2014, 21:58 
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Joined: 08 Aug 2009, 03:11
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Location: Chilliwack, BC
I totally understand! This is the guy whose store I work out of the back in ---> www.classicsound.ca :D

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 Post subject: Re: I'm at it again
PostPosted: 28 May 2014, 21:26 
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Here are some photos of the completed turntable. All 35 pounds of it. It has spiked feet, but they don't show well in the photos.

Good listening
Bruce
Attachment:
701B.jpg
Attachment:
701A.jpg


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 Post subject: Re: I'm at it again
PostPosted: 28 Sep 2014, 20:30 
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Location: Arizona, USA
The saga continues.....I had to do some trouble shooting on the motor last week. It was acting up, occasionally would not start and then on other times go into super speed. It took a while to get a schematic for it as there are about 4 versions of the EDS1000 motor it uses. A faulty capacitor was causing the problem. So since it was apart and I really was tired of all black turntables (I still have another one) I made a new plinth. This one is also of laminated wood. When I finished the gluing it, I thought the grain was so nice that I would not paint it. I just used clear coat on it. The TT works great and certainly is a change from the standard colors.

Good Listening
Bruce
Attachment:
Dual 701 front view.jpg
Attachment:
Dual 701 side view.jpg


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 Post subject: Re: I'm at it again
PostPosted: 29 Sep 2014, 02:27 
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Looks great! :D

gofar99 wrote:
.....I had to do some trouble shooting on the motor last week. It was acting up, occasionally would not start and then on other times go into super speed. It took a while to get a schematic for it as there are about 4 versions of the EDS1000 motor it uses. A faulty capacitor was causing the problem.


I have a love/hate relationship with that motor for that reason (the 721 uses it too, IIRC).

Had one in the shop that had a serious "wow" problem. Recapped it, pulled the motor apart and regreased the bearings, etc. After 36 man-hours (for the lousy estimate fee) and by process of elimination, came to the conclusion it was a bum irreplaceable Hall sensor :bawling:

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 Post subject: Re: I'm at it again
PostPosted: 29 Sep 2014, 10:09 
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A great motor, but certain parts like you found are impossible to replace. Mine has served me since 1979. This is the first problem since then. Rock stable and vibration free. Lots of newer stuff is not anywhere as good. It would cost a fortune to make one like it now. Even the better new direct drives don't have the error correction the EDS has. They do however use quartz references.

Good listening
Bruce

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 Post subject: Re: I'm at it again
PostPosted: 30 Sep 2014, 12:27 
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Joined: 28 May 2008, 21:53
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Location: Winnipeg, CANADA
Looking good Bruce. Have you had a chance to experiment with other plinth material. Layered plywood might be good from a weight, strength and resonance perspective. The natural wood is a nice look. Most new turntables now come with a choice of fashionable bright pastel colors - kinda like getting a new car.

Cheers

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 Post subject: Re: I'm at it again
PostPosted: 01 Oct 2014, 02:24 
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Joined: 09 Oct 2012, 19:43
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Location: Vancouver Canada
Gio wrote:
The natural wood is a nice look. Most new turntables now come with a choice of fashionable bright pastel colors - kinda like getting a new car.

Yes and they come with built in DAC all for 169.95. Ha ha ha thank you Gio I have not had a good laugh like that in long time.


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 Post subject: Re: I'm at it again
PostPosted: 02 Oct 2014, 14:24 
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Joined: 04 Jun 2008, 20:59
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Hi, yes I think I'll paint the next plinth purple with yellow dots....sort of urban camouflage. I have tried a number of different materials. It seems with the Dual motor assembly it doesn't make much difference what is used. All are quiet and sound fine. I suspect that a lot of this is due to the massive weight of the motor and platter. It is about 11 pounds all by itself. So with a plinth of 5 pounds or more the collective mass is sufficient to damp any resonances. One area that does matter is the "feet". They need to be soft and pliable to absorb any room vibrations. In my case they are minimal as the turntables are on strong individual shelves fastened to the outside wall of the house (brick). So anything short of a sonic boom will not influence them. Back to the materials though....if you mix plywood with soft or hard woods you can have some problems. Here there is a huge seasonal shift in humidity. In the winter it is below 10% most of the time and in the summer over 75% most of the time. If the wood is not really well sealed the different types have a tendency to expand and contract differently and the plinth can warp. I had one do that that was made of three layers.....hardwood plywood and pine.

Good listening
Bruce

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