[78-L] Extra long Lps, was Re: 10" vs. 12" LPs

[Bertrand CHAUMELLE]

Le 13 sept. 09, à 21:48, Michael Biel a écrit :

> From: Bertrand CHAUMELLE <chaumelle at orange.fr>
>> What about the Trimicron MDR LPs ? Up to 60 minutes of music
>> in stereo per side. MDR was E. Rabe's process (Magnetic Disc 
>> Recording).
>
> Was this magnetic or a mechanical grooved system?
***A mechanical grooved system
>
>> MDR also invented a videodisc system (12", 20 minutes per side,
>> 120rpm). It was demonstrated in Paris in 1974; the same machine
>> could be used to play LPs, too.
>
> So this was grooved?  Of course there was the RCA CED grooved videodisc
> and Leah and I have well more than 100 of these.
***The inner area was grooved to serve as a guide for the outer area 
(magnetically recorded).
I remember CED (Selectavision); I've seen a demo in Paris around 1975. 
And before that the German Teldec videodisc was grooved (vertical cut).
>
>
>> I've never seen an evaluation of the system in print,
>> but I own several of their 12" and 7" records.  BC
>
> Fine grooved 33 1/3?
***Yep. It was cut using a "sinusoidal" method to minimize the space 
between the grooves (I hope it makes sense).
>
> _______________________________________________
> 78-L mailing list
> 78-L at klickitat.78online.com
> http://klickitat.78online.com/mailman/listinfo/78-l