Switching S/PDIF

[christo]

Here's an URL w/ascii schematics, which some kind souls posted, of some
SPDIF circuits which buffer between TTL and SPDIF levels & backwards.

The one at the end of the page is best 'cause it uses the 74HCU04 which
exhibits the proper behavior (unlike the gnarly 74HC04!!).

http://www.digitalexperience.com/soundpro.html

Note, S/PDIF at the physical interface level is +/- 0.5V.

And (besides the use of extra reserved fields in the data stream) AES/EBU
is a several times higher voltage.

Anybody know the exact voltage levels?