How does a record player recover stereo?

[Jacobe Hazzard]

With vinyl records, a needle travels through grooves cut into the vinyl. The
travel is converted to an electrical signal via the piezoelectric effect or
some other microphonic pickup attached to the needle.

How is it that with one needle only, one is able to reproduce a stereo
signal from vinyl?

Adam

 

[John Popelish]

Jacobe Hazzard wrote:

With vinyl records, a needle travels through grooves cut into the vinyl. The
travel is converted to an electrical signal via the piezoelectric effect or
some other microphonic pickup attached to the needle.

How is it that with one needle only, one is able to reproduce a stereo
signal from vinyl?

Adam

One channel is encoded in the movement 45 degrees from vertical to one
side, and one channel is encoded in movement 45 degrees from vertical
to the other side. If you were miniaturized, and traveling down the
grove as if you were the tip of the diamond, you would experience
motion up and right to down and left for one channel, and down and
right to up and left for the other channel. A mono recording encodes
a single channel by pure side to side motion, which produces equal and
in phase signals from the two stereo channels.

--
John Popelish

 

[John Larkin]

On Thu, 10 Jul 2003 23:41:13 GMT, "Jacobe Hazzard"
<jacobe-hazzardR-E-M-O-V-E@eudoramail.com> wrote:

With vinyl records, a needle travels through grooves cut into the vinyl. The
travel is converted to an electrical signal via the piezoelectric effect or
some other microphonic pickup attached to the needle.

How is it that with one needle only, one is able to reproduce a stereo
signal from vinyl?

Adam

Picture a v-shaped groove. One wall moves to encode one channel, and
the other side codes the opposite channel. The pickup separates the
orthogonal motions into separate electrical signals.

John

 

[paul s]

Jacobe Hazzard wrote:

With vinyl records, a needle travels through grooves cut into the vinyl.
The travel is converted to an electrical signal via the piezoelectric
effect or some other microphonic pickup attached to the needle.

How is it that with one needle only, one is able to reproduce a stereo
signal from vinyl?

Horizontal and vertical movement of the stylus 'needle'. together with two
transducers.

Gives the history of stereo vinyl and how it works:
http://www.badenhausen.com/VSR_History.htm
--
Paul S