When Duende plug-ins are used, the audio data to be processed by Duende is sent to the Duende DSP engine by the host application. The audio is then processed by the DSPs and sent back to the host application.
This transfer of audio data produces latency (delay) in the audio signal being processed. Latency time is dependant on the sample rate, type of plug-in(s) loaded and the audio interface buffer setting.
If this latency is not compensated for, the processed audio will arrive late in relation to the unprocessed audio. Generally, the more processing that takes place on a particular signal, the later it will arrive back in the host.
Most host applications automatically compensate for this latency by simply turning on the Plug-in Delay Compensation (PDC) or similar, usually found in the applications preferences. Some hosts even provide full plug-in delay compensation throughout the entire signal path, including sends, groups, and buses.
The location of the settings for the PDC option within some common host applications is as follows:
• Cubase SX 2/3, Nuendo 2/3:
Always on unless the ’Constrain Delay Compensation’ feature is used to disable delay compensation on individual plug-ins: Devices Menu>Plug-in Information>Use Delay Compensation
• Logic Pro: Preferences>Audio>General
• Ableton Live: Options>Delay Compensation
• Pro Tools HD: Setup>Playback Engine>Delay Compensation Engine>Long (4095 Samples per channel)
Important: Delay compensation is fully automatic and requires no user intervention when Duende plug-ins are used in hosts that support Full Plug-in Delay Compensation.
Depending on the host application implementation, the delay compensation feature may not provide automatic compensation when Duende plug-ins are inserted on sends, groups, or buses. In this situation, the solution is to manually compensate for the plug-in delay.
Please note this applies primairly to Duende v2 software. The latency figures are reduced significantly with Duende V3 software, and we recommend using V3 if your system meets the minimum specifications.