Technical information

Apollo Software Manual Chapter 11: Latency & Apollo 178
Chapter 11: Latency & Apollo
Delay Compensation with Apollo
System Latency Overview
System latency encapsulates all latencies induced within the typical digital audio work-
station environment. See “Latency Basics” on page 181 for a detailed overview of
where, when, and how latency is induced in this environment.
Driver Reporting
Any system latency that is induced by Apollo’s I/O, Console, and/or UAD Powered Plug-
Ins is reported by Apollo’s device drivers to the host audio software that is using the
device.
The host software uses this reported device latency for its automatic delay compensation
(ADC) engine. When properly configured in the DAW, ADC maintains phase coherency
(time alignment) throughout the recording, overdubbing, and mixing process.
Automatic Delay Compensation in the DAW
Generally speaking, ADC should be enabled in the DAW when using Apollo, regardless of
whether or not Console is used concurrently. The DAW’s ADC will perform the necessary
housekeeping to keep tracks phase-aligned, regardless of the latency source (if any).
Input Delay Compensation in Console
Console has automatic Input Delay Compensation (IDC), which is controlled by the Input
Delay Compensation menu in Console Settings. Console IDC maintains phase alignment
across all Console’s analog and digital inputs when upsampled UAD plug-ins are used in
Console.
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, without in-
put delay compensation, the phase of the two mic channels would no longer be aligned.
How Console IDC works
Console IDC automatically adds small amounts of delay to each Console input that is not
delayed by upsampled plug-ins, so all Console inputs are still phase aligned. In other
words, all compensated inputs are automatically delayed by the same amount.