Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/18/84; site nmtvax.UUCP Path: utzoo!linus!philabs!cmcl2!lanl!unm-la!unmvax!nmtvax!c20 From: c20@nmtvax.UUCP Newsgroups: net.audio Subject: Re: Tuner Leakage Problem... Message-ID: <853@nmtvax.UUCP> Date: Tue, 5-Nov-85 15:54:44 EST Article-I.D.: nmtvax.853 Posted: Tue Nov 5 15:54:44 1985 Date-Received: Fri, 8-Nov-85 06:15:00 EST References: <4960004@acf4.UUCP> <276@mit-eddie.UUCP> Organization: New Mexico Tech, Socorro Lines: 49 > > things about tuner leakage here ... > > I've been wondering about something related to playing records that bugs > the hell outta me - on some records there is a very faint "ghost" of sorts > that comes about a second or so before the real signal (eg. when listening > during the space between songs, the beginning of the ensuing song can be > heard faintly to precede the actual music by about a second). Some of the > records I have (like OMR's and other half-speed masters) are pleasingly > free of this disturbance. > > The question in my mind is this: are there any turntables around that > can handle this sort of quirk? Also, how on earth do the recording > companies get away with this sort of bad-quality production? Ack. > -- > > -Mike > > genrad!mit-eddie!zzz (UUCP) ZZZ%MIT-OZ@MIT-MC (ARPA) This "ghosting" effect is caused by making a record with the grooves too close together for the recording level. When the record is pressed, the vinyl between the grooves is stressed slightly (note: the vinyl is slightly warm at this point). After the die is removed from the record, the record begins cooling. However, before it cools enough, the stressed plastic *between* the grooves begins relaxing, and each groove takes on a little of the waveform of the NEXT groove. If you check, you should find that the ghost sound starts exactly one revolution (slightly less than two seconds at 33.333 rpm) before the equivalent real sound begins. It's bad enough to hear the ghosting effect before the song starts, but it's worse when you realize that if this happens on the first groove, it's probably happening on all the other grooves too. So every part of the music you hear has this not-quite-hearable "fuzz" on top of it, which is the very-quietly-played sound of both of the adjacent grooves. A record company can prevent this either by increasing the inter-groove spacing, or by making quieter records (i.e., records with smaller wiggles in the grooves) greg -- Greg Titus ..!ucbvax!unmvax!nmtvax!c20 (uucp) NM Tech Computer Center ..!cmcl2!lanl!nmtvax!c20 (uucp) Box W209 C/S c20@nmt (CSnet) Socorro, NM 87801 c20.nmt@csnet-relay (arpa) (505) 835-5735 ======================================================================