stereo records

psyfi

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This is just something that I've wondered about. A record player has one needle sitting in a groove on a vinyl record as it spins about the variations of the groove move the needle and that movement is amplified and out comes you noise but as there is only one needle how is a stereo signal produced. :? I've thought about it and my brain can't figure it out.

I bet the answer really simple..
 
I asked a DJ friend of mine about this some time ago and he had no idea ether.
Maybe it’s a conspiracy. If it says stereo on the sleeve then we think it is.
 
each side of the stereo is encoded on one side of the groove or the other and the needle can pick up vertical as well as horizontal movement...
Or something like that :runaway:
 
so one channel is on the vertical and the other is on the horizontal. If I understand you correctly. arrrhhh

:wo^thy:
 
The stereo information is carried in the diagonal movement of the needle. ;)
The tracks are cut with left and right out of phase, producing a mono (lateral) groove, the stereo difference effectively modulates the vertical part of the groove. Though the playback cartridge should, read this as two separate signals.
Vinyl offers very poor stereo separation at low frequencies, and often ends up with a much stronger low frequency component on the left had channel. :unsure:
Ortofon used to have a lot of information on this subject, though it’s been 15 years or so since I read it. :?
 
Plank! said:
Vinyl offers very poor stereo separation at low frequencies, and often ends up with a much stronger low frequency component on the left had channel. :unsure:
That is why they monofy everything below 300Hz or so in the mastering. The larger in wavelenght and amplitude low frequencies will throw the needle of the record if they have major phase differences between them.
Anyway, the human brain cannot perceive directionality for low frequencies, so it's all good.

Peace.
 
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