Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!csd4.milw.wisc.edu!leah!rpi!nyser!njin!princeton!siemens!demon!fwb
From: fwb@demon.siemens.com (Frederic W. Brehm)
Newsgroups: sci.electronics
Subject: Re: RS-232 for voice
Message-ID: <12663@siemens.siemens.com>
Date: 27 Jul 89 18:19:25 GMT
References: <8616@cbnews.ATT.COM>
Sender: news@siemens.siemens.com
Reply-To: fwb@demon.UUCP (Frederic W. Brehm)
Distribution: usa
Organization: Siemens Corporate Research
Lines: 22

In article <8616@cbnews.ATT.COM> knt@cbnews.ATT.COM (kirk.n.trost) writes:
>
>Can fairly good sounding voice be sent digitized over
>RS-232 ???

About 10 years ago, I visited KDD Laboratories in Tokyo.  They showed a
demo of sending compressed continuous speech over a 1200-baud RS-232
channel (actually CCITT V.2?).  The speech was understandable, but it was
difficult to identify the speaker.  Higher speeds would allow less
draconian compression methods, and better quality.  I think that
telephone-bandwidth speech at 64K bits/sec does not need to be compressed
(someone in your company should know).

But they were using a synchronous (not asynchronous :-) signalling method
over RS-232.  Are you asking if speech can be sent over a standard
asynchronous 8-bit data without parity + 1 start bit + 1 stop bit terminal
port?  What speed?  How good is "fairly good"?

Fred
--
Frederic W. Brehm	Siemens Corporate Research	Princeton, NJ
fwb@demon.siemens.com	-or-	princeton!siemens!demon!fwb