USER’S MANUAL
Section 11: THE WORKS – Detailed Menu Reference 207
c
COMPTIBILITY TIP!
The Zephyr Xstream cannot receive two stereo feeds from the far end (after all, where would
the audio be output?).
When connected to two different sites simultaneously, you can receive an audio feed back
from each using G.722 or L3 Dual/Mono.
AAC
Stereo
AAC
J
‐
Stereo
These
work
similarly
to
the
equivalent
Layer
‐
3
modes
(see
above).
Two
connections
are
required.
These
modes
are
important
since
they
offer
the
best
quality
ever
over
a
single
ISDN
BRI
circuit.
Offers
15
kHz
audio
frequency
response,
when
the
sample
rate
is
set
to
32
kHz
and
20
kHz
response
when
the
sample
rate
is
set
to
48
kHz.
AAC
Mono
128
This
uses
both
B
channels
transmit
a
single
audio
channel
using
the
audio
from
input
A.
Offers
15
kHz
audio
frequency
response
when
the
sample
rate
is
set
to
32
kHz
and
20
kHz
response
when
the
sample
rate
is
set
to
48
kHz.
c
COMPATIBILITY TIP!
When two channels are required for transmission (i.e. for Stereo, J-Stereo, and Mono 128) an
"inverse multiplex" (IMUX) scheme must be used to break the standard MPEG data stream
into two streams for transmission.
In AAC and AAC-LD, the Zephyr Xstream uses the Telos Zephyr IMUX protocol.
AAC
Mono
64
This
encodes
a
single
mono
bit
stream
using
the
A
audio
input.
This
bit
stream
is
fed
to
both
ISDN
B
channels
so
it
can
be
to
feed
identical
mono
to
two
sites.
Offers
15
kHz
audio
frequency
response
when
the
sample
rate
is
set
to
32
kHz
and
20
kHz
response
when
the
sample
rate
is
set
to
48
kHz.
G.722
(Dual/Mono)
Compatible
with
many
other
brands
of
codecs.
We
use
the
SRT
(Statistical
Recovery
Timing)
method,
which
is
the
most
common
encountered
by
far.
Summary of Contents for Zephyr Xstream
Page 2: ......
Page 26: ...USER S MANUAL Section 1 QUICK RESULTS 14...
Page 30: ...USER S MANUAL Section 2 INTRODUCTION Getting to Know the Zephyr Xstream 18...
Page 70: ...USER S MANUAL Section 3 GUIDED TOUR of the HARDWARE 58...
Page 144: ...USER S MANUAL Section 6 AUDIO CODING REFERENCE 132...
Page 164: ...USER S MANUAL Section 8 LIVEWIRETM IP Audio 152...
Page 310: ...USER S MANUAL Appendix 1 Codec Interoperability Information 298...
Page 320: ...USER S MANUAL Appendix 3 ISDN Cause Phrases Values 308...
Page 324: ...USER S MANUAL Appendix 4 Known Working SPID Formats by Telco 312...
Page 356: ...USER S MANUAL Appendix 9 Modular Cable Guide 344...
