This is related to a post I made in the feature request forum... I noticed on large projects with lots of plugins, there was a noticeable latency when playing VST synths with an external MIDI device...
I've played around a bit more & it turns out the latency only occurs when there are plugins on the master bus... plugins everywhere else do not result in MIDI latency for playing softsynths, but plugins on the master bus do...
Is there any way this can be resolved? Atm it appears latency for master bus plugins is not totally compensated...
PDC, midi & the master bus
Hi Vance,
I am not sure if I understand what you mean. Please correct me if I am wrong.
Assuming you have a Live set containing only a VSTi located in a MIDI track.
With an external MIDI device (like a keyboard for instance) you can play this VST. So far so good.
But when you add a VST to the master you get a delayed response. In this case the delay is caused by the VST because it is processing audio in buffers. So its output is at least delayed by the length of this buffer. This buffer size again can be setup in the "Plug-In" section within Live's preferences.
Is it that what you mean?
regards,
/Alex
I am not sure if I understand what you mean. Please correct me if I am wrong.
Assuming you have a Live set containing only a VSTi located in a MIDI track.
With an external MIDI device (like a keyboard for instance) you can play this VST. So far so good.
But when you add a VST to the master you get a delayed response. In this case the delay is caused by the VST because it is processing audio in buffers. So its output is at least delayed by the length of this buffer. This buffer size again can be setup in the "Plug-In" section within Live's preferences.
Is it that what you mean?
regards,
/Alex
Hi Vance,
unfortunately there is no way to reduce this kind of latency to 0.
Look, in the above sample you have to deal with the following latencies.
1) The time needed from pressing up a key on your MIDI keyboard until it reaches the MIDI driver of your MIDI interface in the computer. This latency is really low, so actually we can ignore this one.
2) The processing time of the VSTi. This depends on the buffer size that is used for the Plug-In. This buffer size can be setup in the "Plug-In" section within Live's preferences. By default it is 128 samples.
3) The processing time of the VST in the master track. It is the same buffer size as for the VSTi
4) Finally the output latency of your audio interface. This depends on the buffer size of your audio interface which you can set up in the "Audio" section of Live's preferences.
So your only way to reduce the latencies is to make them a small as possible. When you go to the "Plug-In" section of Live's preferences and change the BufferSize between 32 (minimal value) and 4096 (maximal value) you should noticed a audible difference in response.
Same is valid for the buffer size of your audio interface.
regards,
/Alex
unfortunately there is no way to reduce this kind of latency to 0.
Look, in the above sample you have to deal with the following latencies.
1) The time needed from pressing up a key on your MIDI keyboard until it reaches the MIDI driver of your MIDI interface in the computer. This latency is really low, so actually we can ignore this one.
2) The processing time of the VSTi. This depends on the buffer size that is used for the Plug-In. This buffer size can be setup in the "Plug-In" section within Live's preferences. By default it is 128 samples.
3) The processing time of the VST in the master track. It is the same buffer size as for the VSTi
4) Finally the output latency of your audio interface. This depends on the buffer size of your audio interface which you can set up in the "Audio" section of Live's preferences.
So your only way to reduce the latencies is to make them a small as possible. When you go to the "Plug-In" section of Live's preferences and change the BufferSize between 32 (minimal value) and 4096 (maximal value) you should noticed a audible difference in response.
Same is valid for the buffer size of your audio interface.
regards,
/Alex
Thanks for the explanation Alex 
I could've sworn I'd never noticed such a delay in other hosts but having just checked, sure enough they're there...
Would it be possible to allow plugins only to have the delay when they're turned on? At the moment plugins on the master bring a delay even when they're off (and therefore not processing anything)... if it's possible for turned-off plugins not to delay things in this way that'd be cool...
I could've sworn I'd never noticed such a delay in other hosts but having just checked, sure enough they're there...
Would it be possible to allow plugins only to have the delay when they're turned on? At the moment plugins on the master bring a delay even when they're off (and therefore not processing anything)... if it's possible for turned-off plugins not to delay things in this way that'd be cool...
Hi Vance,
So when having several tracks with several plug-ins and PDC enabled, switching on /off such a plug-in would each time change the sync of these tracks together, which is very probably not what you want.
regards,
/Alex
I can understand that in some scenarios it would be ok but there are also scenarios where this would get out of sync. Switching off the plug-in in any track would then reduce the processing delay of this plug-in to 0.if it's possible for turned-off plugins not to delay things in this way that'd be cool...
So when having several tracks with several plug-ins and PDC enabled, switching on /off such a plug-in would each time change the sync of these tracks together, which is very probably not what you want.
regards,
/Alex
Last edited by Alex on Thu Dec 08, 2005 3:42 pm, edited 1 time in total.
