Vienna Symphonic Library Forum
Forum Statistics

181,837 users have contributed to 42,188 threads and 254,610 posts.

In the past 24 hours, we have 4 new thread(s), 30 new post(s) and 55 new user(s).

  • Latency Compensation – Need Help Understanding

    I’ve never totally understood latency compensation in VEPro and now with the new Pro Tools 9 which finally has automatic delay compensation I’m even a little more confused. I think I have a few questions but I'll start by asking one and see if I can get someone to respond:

    The VE PRO manual says,”The Vienna Ensemble PRO Server Interface plug-in automatically compensates the latency in playback”.  Can someone tell me then – Does that mean that, during playback, the plugin knows what notes are going to be played before hand and triggers the notes early by the amount of the latency setting? And if that is so – does it trigger them early by the amount of the buffers added or also the amount of the soundcard latency setting?


  • No, Latency Compensation it doesn't trigger the notes early, the way it works is just the contrary, it delays the events so all are triggered at the same time.

    Some plugins need to have a bigger process buffer than others, which translates to additional delays in the signal. Many Impulse reverbs, compressors and limiters have additional buffers to improve their accuracy.

    Let's say you have a high quality limiter that has some latency. What happens if you use the plugin in one channel but not in others? the channel with the limiter inserted will sound a bit later, because the process buffer is larger on it.

    Latency compensation ensures that all channels sound at the intended time, independently of the plugin chain and their latencies, and without the user having to deal with it. The only way to do this is delaying all the signals to the most delayed one.


  • Thanks for your explanation. I’m still confused though. What you described to me sounded like the explanation of how latency compensation is done by the DAW software like my new ProTools 9 (which now performs automatic delay compensation finally). This I think I understand how that it finds the track with the most latency and then makes sure all the other tracks are delayed just as much so everything plays in sync. This I can understand because ProTools (or Cubase or DP) has control of all the different tracks.

    But my question was not how does ProTools do this but rather how does the Vienna Ensemble PRO Server Interface plug-in do this? Again the manual says,”The Vienna Ensemble PRO Server Interface plug-in automatically compensates the latency in playback.” So how does it do this?  Is the plugin so smart that it can look at all the other tracks playing and slow them down by the amount needed so that everything plays in sync? If so that seems very impressive to me. Or maybe I just don’t understand so well. Tell me more please.


  • I really do need to get some answers on this subject. Especially since ProTools 9 now has automatic delay compensation also. I need to know what's doing what. Is the VEPro plugin compensating AND ProTools or what? And I need an answer to the question from my previous post as well.  Could somebody from VSL speak up about this?  (And why does "Normal 0" show up at the top of my posts?)


  • The VE Pro Server Interface plugin reports its latency to the host, which is responsible for the delay compensation.


  • Karel. Thanks for speaking up and making that clear to me. I've been using Pro Tools 8 LE all this time which didn't have automatic delay compensation built into it. I think I got thrown off by the VE Pro manual where it says, ”The Vienna Ensemble PRO Server Interface plug-in automatically compensates the latency in playback” because it didn't also say, "assuming your host has the ability to do delay compensation". Of course ProTools 9 does have it now so everything is making sense.


  • I have a question regarding the Delay compensation WITHIN vienna ensemble pro. I know that logic (in my case) takes care of the delay compensation but what i noticed today is that when i started to mix my drums within VEP it was not ligning up. Example: i put a compressor on the SN top on a multichannel instrument and it was alittle delayed because of that plugins internal delay. Is there a way round that or am i gonna have to do the mixing inside logic? best /DAniel

  • Currently there is no automatic latency compensation inside a VE Pro instance, but this is already implemented for the next major update of VE Pro.