[BC] Turntables (WAS:Achieving good S/N)

[Robert Orban]

At 02:08 PM 1/1/2006, you wrote:
>From: Rich Wood <richwood at pobox.com>
>Subject: Re: [BC] Turntables (WAS:Achieving good S/N)
>To: Broadcast Radio Mailing List <broadcast at radiolists.net>
>Message-ID: <7.0.0.16.2.20060101110110.06896c88 at yahoo.com>
>Content-Type: text/plain; charset="us-ascii"; format=flowed
>
>------ At 07:03 PM 12/31/2005, Powell E. Way III W4OPW wrote: -------
>
> >They sent me a CD of records being played. I was very
> >UNimpressed with it. Bass response was very lacking
> >and did not sound clean. NOT with my money....IF I had
> >it to spend.
>
>I think I remember a comment that the record had to be perfectly
>flat. The concept is a little like a CD where the laser reads beyond
>the protective layer. It's supposed to ignore micro-mountains
>(scratches) and read only the groove impressions. If the record is
>cut too loud, everything gets interpreted as bad data (which it is)
>and it sounds much worse than a needle in a groove. I also recall
>that it couldn't read any vertical component in the groove. Anything
>vertical was seen as a scratch. What makes it worse is that the 500
>KV power transmission cable leading to the preamp carries it, in all
>its perfection. I'm going to copyright, trademark and service mark
>"King Kong Kable," at least as long as the movie continues to be a success.

The laser TT can track moderately warped records. It uses five laser beams, 
one of which is used in a "height servo" mechanism.

http://www.laserturntable.com/about/how.html

The statement of not reading vertical components in the groove is nonsense. 
The vertical modulation of the groove represents the stereo difference 
signal (L - R). Any record player unable to read the vertical modulation of 
the groove is, by definition, a mono player.

Bob Orban