Universal Audio Apollo Software - Manual (Page 111)

Apollo Software Manual Chapter 8: Latency & Apollo 111
Although the latency added by upsampled UAD plug-ins is negligible (typically between
0-300 samples, depending on the plug-in and sample rate), this extra latency can affect
phase coherency in a session. For specific latency values, see
“Upsampled UAD Plug-Ins
Table” on page 113 .
For example, if two microphones are used on an acoustic source (such as a drum kit) and
an upsampled plug-in is used on one of the mic channels but not the other, the phase of
the two mic channels will no longer be aligned.
When To Use Console Input Delay Compensation
Console IDC is required to maintain phase alignment only when BOTH of the following
conditions are active:
1. Multiple Console inputs are used for a single source (such as a drum kit using
multiple microphones), and
2. Any of those input channels contain upsampled UAD plug-ins.
Tip: When IDC is not needed, disable Console IDC for the lowest possible input
latency.
Effect of Console’s IDC setting
In Console
In Console, the amount of delay added by the IDC engine is automatic. Only the mini-
mum amount of delay actually required to compensate the input(s) is applied (up to the
maximum value of the setting), maintaining the lowest possible latency for phase align-
ment at all times.
For example: When the IDC value is Short (100 samples – the default value) and only 31
samples is actually required to compensate, then only 31 samples of delay will be ap-
plied to the other Console inputs.
In the DAW
In the DAW, the amount of delay added by Console’s IDC
engine is static. The extra samples are always added to
all inputs in the DAW, even if no upsampled plug-ins are
active. However, this overall additional input latency is
reported by Apollo’s drivers, so it is automatically compen-
sated by the DAW’s ADC.
For example: When the IDC value is Short (100 samples –
the default value) and only 31 samples is actually required to compensate, 100 samples
is still added to all inputs in the DAW. If using software monitoring via the DAW, the extra
(unnecessary) delay could be detected.
Note: By default, Console Input Delay Compensation is enabled with the Short
value (100 samples).
Input Delay Compensation Values
Setting Name Extra Delay (samples)
Off 0
Short 100
Medium 200
Long 1000