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- Xref: sparky sci.electronics:13441 rec.audio:10925 alt.folklore.computers:11266
- Newsgroups: sci.electronics,rec.audio,alt.folklore.computers
- Path: sparky!uunet!telebit!eric
- From: eric@telebit.com (Eric Smith)
- Subject: Re: Life after CDs
- In-Reply-To: edhall@rand.org's message of 26 Jul 92 23:05:49 GMT
- Message-ID: <ERIC.92Jul28010349@iceland.telebit.com>
- Sender: news@telebit.com
- Nntp-Posting-Host: iceland.telebit.com
- Organization: Telebit Corporation
- References: <ERIC.92Jul23182226@napa.telebit.com>
- <1992Jul26.155337.14069@news.columbia.edu>
- <ERIC.92Jul26155404@iceland.telebit.com> <3647@randvax.rand.org>
- Date: 28 Jul 92 01:03:49
- Lines: 22
-
- >>On 26 Jul 92 23:05:49 GMT, edhall@rand.org (Ed Hall) said:
- > Even the cheapest VCR will have no problem locking onto a signal 0.1%
- > faster than NTSC. Consumer video cameras/camcorders can be off by more
- > than that.
-
- That's correct. The problem is usually using the tape as a source. If the
- VCR is adjusted to spec, the vertical sync rate on playback will be 59.94 Hz,
- even if the tape was orginally recorded with a 60 Hz rate. If you pass a
- PCM encoded audio signal from this player to another player that can handle
- the 0.1% error, you can dub it fine. But you may not be happy if you try to
- listen to it, as the D/A system will either lock to the lower speed, or
- have sample slips.
-
- > This is good, since sample-rate conversion between 44.1Ks/s and 44.056Ks/s
- > is pretty tricky and computationally expensive.
-
- Computationally expensive is relative. I wouldn't try to do it in real time
- on my 486 machine, but a $10 integer DSP chip with about $15 worth of fast
- static RAM can do it.
-
- Cheers,
- Eric
-