[comp.dcom.telecom] Voice Compression on MCI Trunks?

HPAGE@ibm.com (02/05/91)

I've had the honor of using MCI's LD service lately. The voice quality
on a significant of my calls from the East Coast to the West Coast is
slightly distracting. There seems to be some type of speech detecting
circuit that annoyingly clips the first several hundred milliseconds
off the voice of the called party. If the called party's transmitting
power is very low, which is the case when he/she has a soft voice or
is using "cheap" phone, there is intermittent cut outs of the speech.
In addition, interestingly enough, when the circuit is idle there is a
moderate amount of circuit (white) noise in the background that
disappears as the called party speaks.

I'm guessing that MCI is using some type of fast packet voice
compression technology (hence the speech detection/clipping).

Anybody know the definitive story?


Howard G. Page      hpage@ibm.com

PMW1@psuvm.psu.edu (Peter M. Weiss) (02/06/91)

In article <16713@accuvax.nwu.edu>, HPAGE@ibm.com says:

>I've had the honor of using MCI's LD service lately. The voice quality
>on a significant of my calls from the East Coast to the West Coast is
>slightly distracting. There seems to be some type of speech detecting
>circuit that annoyingly clips the first several hundred milliseconds
>off the voice of the called party. (deleted)

What does this do to modem data calls?


Peter M. Weiss                   | pmw1 @ PSUADMIN
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