E-MU 1616M PCIe - Manual (Page 26)

4 - The PatchMix DSP Mixer
The Session
26 Creative Professional
The System Settings include the following:
E Note: if set to
“External” without an
external clock present,
PatchMix DSP defaults to
the internal 48kHz clock
rate.
Using External Clock
Whenever you are using any digital I/O such as ADAT or S/PDIF, one of the digital
devices MUST supply the master clock to the others. This master clock runs at the system
sample rate and can be embedded into a data stream such as S/PDIF or ADAT.
Common symptoms of unsynced digital audio include, random clicks or pops in the
audio or failure of the digital stream to be recognized. Always check for the presence of
the “LOCKED” indicator whenever you are using a digital interface.
If an External Clock is interrupted or switched after the Session has been created (except
between 44.1k <-> 48k), the “LOCKED” indicator
will be extinguished and PatchMix
will attempt to receive the external data. The two units are NOT sample locked however,
and you should correct this condition to avoid intermittent clicks in the audio.
I/O Settings
You can set the level (-10dBV or +4 dBu) for each pair of analog outputs and the input
gain setting for each pair of analog inputs.
An output setting of +4 provides the most output and is compatible with professional
audio gear. Balanced output cables provide a +6dB hotter signal than unbalanced cables
when used with balanced inputs. Do NOT use balanced cables unless your other gear
has balanced inputs. See
“Cables - balanced or unbalanced?” in the Appendix for more
information.
f Input too weak?
Use -10 Input setting.
Output too weak?
Use +4 Output setting
An input setting of -10 is compatible with consumer audio gear and works best with low
level signals. (-10dBV is approximately 12dB lower than +4dBu.) Choose the setting that
allows you to send or receive a full scale signal without clipping.
Setting correct input and output levels is important! You can measure the level of an
input by inserting a meter into the first effect location in the strip. Adjust your external
equipment outputs for the optimum signal level. See
“To Set the Input Levels of a Strip”
for details.
• Internal/External Clock Selects between internal or external word clock source
as the master clock source for the system
• Sample Rate Selects the sample rate when using internal clock.
Your choices are: 44.1kHz, 48kHz, 88.2kHz, 96kHz,
176.4kHz, 192kHz.
• External Clock Source
(ext. clock only) Select from: ADAT, or S/PDIF as an external sample clock
source.
Consumer
Headroom
Headroom
Professional
+20 dBu
+8 dBu + 6 dBV
+4 dBu + 2 dBV
-8 dBu
=
=
= -10 dBV
{
}
Clipping -->
<-- Clipping
(balanced) (unbalanced)
Comparison of -10dBV & +4dBu Signal Levels
0 dBV = 1V RMS 0dBu = .777V RMS