Re: [linux-audio-user] latency compensation

On Fri, 2005-07-22 at 10:31 -0400, Brett McCoy wrote: Quite simple, actually. This example is for Ardour, but it should work in all Linux software which respect and use the latency values reported by some LADSPA plugins. Say you have a Bus: inputs -> LADSPA 1 -> LADSPA 2 -> INSERT (sp/dif out & in) -> outputs Newer versions of Ardour (currenty only in CVS) & Jack (the to be released 0.100.0) will automatically compensate for the latency caused by jack wiring. The next step is to use the ingenious plugin by Steve Harris: Artificial Latency. This plugin does nothing, except return a specified amount of latency. The amount of latency it reports is controlled like any plugin is controlled. Add the plugin somewhere in the bus's chain (doesn't matter where). Now either measure or calculate (or throw something off the top of your head) the amount of latency of the "sp/dif -> windows -> vst host -> vst(s) -> etc. -> sp/dif out" chain and use that value for the artificial latency plugin. Make sure the plugin is activated, and ardour will compensate for the latency. Not all LADSPA plugins report their latency, sometimes this can be bothersome, but these issues can also be resolved with the artificial latency plugin. It's worth mentioning that even though latency compensation works a bit better in newer versions of Ardour and Jack, this same principle can also be used in earlier versions (like beta29). There are some problems with aligning recorded material which were recorded on tracks with latency compensation. These problems are currently being ironed out. -- Sampo Savolainen <v2(a)iki.fi>