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Hi Doug,

You might want to get in touch with Carl Haber at Berkley. He has  
worked on an optical way to "read" disks. The work he's done on  
cylinders is remarkable. I've had the pleasure of advising him over  
the years and he's a wonderful, intelligent creative thinker.

here's a link to what he's been up to. I think he might be able to  
help you out. If this looks good to you e-mail me and I'll get you  
his e-mail with his approval.

http://sciencematters.berkeley.edu/archives/volume4/issue30/story1.php

Adrian Cosentini
Audio / Preservation Manager
The New York Philharmonic


On Mar 6, 2011, at 6:18 PM, Doug Pomeroy wrote:

> Many thanks George for this info.
>
> I am surprised the ELP won't play lacquers, but that ends the  
> discussion!
>
> Why the broken piece won't fit snugly against the larger piece from  
> which
> it was broken is a real puzzle and something I have never  
> encountered before,
> and I have a lot of experience with broken records.
>
> It means that if I get the grooves to line up perfectly at the rim  
> on one end of
> the broken piece, the grooves will NOT line up on the other end!    
> Dealing with
> a gap is no problem as long as the grooves on both sides of it line  
> up reasonably
> well.
>
> I can tell the lacquer has shrunken slightly, and I can deal with  
> that, but glass
> does not shrink, so why the large pieces won't fit together is  
> truly inexplicable.
>
> DOug
>
> ===========================================================
>
>> Date:    Sat, 5 Mar 2011 16:15:34 +0100
>> From:    George Brock-Nannestad <[log in to unmask]>
>> Subject: Re: ELP turntable
>>
>> From: Patent Tactics, George Brock-Nannestad
>>
>>
>> Hello,
>>
>> I did not want to repeat my praise for the ELP, because the matter  
>> was up not
>> that many months ago, but it does offer spectacular advantages,  
>> such as not
>> having to clean a record before sampling it.
>>
>> But now that we have learnt what it was wanted for, I think it  
>> only fair to
>> mention that lacquer records cannot be played anyway, because the  
>> reflection
>> from the material is too weak. It does not matter whether the rim  
>> has a
>> break; what Mike mentioned would be that there should not be a  
>> bite taken out
>> of it. Shellac records in many pieces loosely held together with  
>> tape on the
>> reverse side will play absolutely fine and will save you many  
>> hours of
>> cementing together the jigsaw. If a bite were missing I would  
>> definitely
>> experiment with a temporary patch that only had to fulfil the  
>> requirement
>> that the reflection should be similar and that there should be no  
>> local
>> sudden change in outer radius. Filing a shard from another record  
>> for a loose
>> fit in the gap might work. I have not tried it. I can foresee  
>> certain issues
>> of groove pitch, but some experimenting would tell. The audio  
>> information is
>> gone from your record in that spot anyway, but the erroneous sound  
>> you get
>> for a few fractions of a second for a few turns of the record can  
>> be edited
>> out/blanked digitally later.
>>
>> I do not think a glass disc broken into two pieces is at all  
>> unsalvageable. I
>> am slightly worried that they do not fit together; at least the  
>> carrier glass
>> should, but perhaps the lacquer layer has shrunk back from the  
>> broken edges.
>> There was one Swiss archival turntable (well, in particular its  
>> pickup) that
>> would work in this situation; it used a trailing optical fiber  
>> that will stay
>> in almost any groove.
>>
>> John R.T. Davies used to have special jigs to support broken  
>> records to be
>> able to play them with a normal pickup, and my personal experience  
>> has been
>> that as long as you ensure that the stylus encounters a step DOWN  
>> at both
>> cracks when playing a record broken in two, you are basically  
>> fine. If you
>> are going to use cement to fill the gap you must think globally:  
>> the two
>> pieces have to be twisted ever so slightly when fitting them, and  
>> the repair
>> will then be good for both sides. Again depending on materials and  
>> care, you
>> may handle the record carefully, e.g. for turning it over, but  
>> obviously it
>> will not tolerate sleeving.
>>
>> We are looking forward to yet another unique jazz find!
>>
>> Best wishes,
>>
>>
>> George
> Doug Pomeroy
> POMEROY AUDIO
> Audio Restoration & Mastering Services
> Transfers of metal parts, lacquers,
> shellac and vinyl discs & tapes.
> 193 Baltic St
> Brooklyn, NY 11201-6173
> (718) 855-2650
> [log in to unmask]
>
> A bird in the hand gathers no moss.
> ----Louis Armstrong