Latency issues with Rewire

Synthbuilder · Post by **Synthbuilder** » Tue Nov 29, 2005 10:34 am

I'm relatively new to Live 5.02 and I am very impressed with the program thus far. However, can anyone confirm one item of behaviour that puzzles me.

I am running Live as a rewire master with Reason as slave. I am doing all my sequencing in Live and taking the outputs of the Reason rack back into Live. Those input channels dedicated to Reason in Live are all set to 'monitor IN' permanently in Live.

It appears that there is always around 13mS [my overall latency] of delay with the Reason output in comparison to any audio or VST tracks in Live. It appears that PDC does not function for Rewired inputs, or perhaps any input channel set to 'monitor IN'.

The workaround appears to be delay all of Live's VST and audio tracks by 13mS with the track delay setting on each channel.

Alternatively, I can also set any midi track that drives Reason to a predelay of -13mS. However, any predelay value more negative than -13mS do not appear to add any more delay.

Is this right that rewired channels aren't compensated for?

Also, can anyone let me know the action of the master track's delay setting. This appears to allow for negative values of predelay, but positive values of delay do not seem to have any affect at all.

Many thanks for any help you can give me.

noou · Post by **noou** » Wed Nov 30, 2005 8:12 pm

hi, I had the very same problem... and as said one from Ableton there's no solution. I mean there's no straight solution: you can resample tracks from Reason (but you get audio and each time you want to change something is a trouble...) furthermore the Abes said that latency compensation doesn't work with Rewire but you can go in a configuration file and manually change the Rewire latency preset value from 256 to a smaller one... this is not working to me. Reason keeps out of sync. Look for other post I made for further infos.

This is really annoying and almost unacceptable in a professional host.
I always used Sonar and never had any issue with rewire.

gomi · Post by **gomi** » Thu Dec 01, 2005 2:01 am

Synthbuilder wrote:I'm relatively new to Live 5.02 and I am very impressed with the program thus far. However, can anyone confirm one item of behaviour that puzzles me.

I am running Live as a rewire master with Reason as slave. I am doing all my sequencing in Live and taking the outputs of the Reason rack back into Live. Those input channels dedicated to Reason in Live are all set to 'monitor IN' permanently in Live.

It appears that there is always around 13mS [my overall latency] of delay with the Reason output in comparison to any audio or VST tracks in Live. It appears that PDC does not function for Rewired inputs, or perhaps any input channel set to 'monitor IN'.

The workaround appears to be delay all of Live's VST and audio tracks by 13mS with the track delay setting on each channel.

Alternatively, I can also set any midi track that drives Reason to a predelay of -13mS. However, any predelay value more negative than -13mS do not appear to add any more delay.

Is this right that rewired channels aren't compensated for?

Also, can anyone let me know the action of the master track's delay setting. This appears to allow for negative values of predelay, but positive values of delay do not seem to have any affect at all.

Many thanks for any help you can give me.

i can confirm, reason will NOT sync to live in rewire mode.
especially when you are using midi clips in live to
trigger reason instruments..

this has stopped me from being able to use reason in a live situation.
i am stuck with simpler and impulse.. which are ok.. but
reason is better.

drez · Post by **drez** » Fri Dec 02, 2005 3:30 am

Yeah, I just figured this out a couple of days ago. Not good.

Does anybody else have this problem in other hosts?

Synthbuilder · Post by **Synthbuilder** » Fri Dec 02, 2005 10:06 am

I have been looking into this a bit more.

Firstly I got a reply from Ableton who confirmed that the rewire input is indeed delayed. I guess one would expect this since rewire is piped into Live as if it were an external audio signal. Thus is therefore bound by the latency problem.

My workaround appears to be fairly straightforward. Every midi channel that controls any Reason synth is predelayed by -10mS, not -13mS as previously stated. The rewire inputs to Live are left at the default 0mS delay. This allows the midi to be in sync with the audio that Live is playing.

I found that delaying the audio channels by 10mS is no good because the metronome is out of kilter with what is being replayed. So you have to predelay the midi.

Note: the -10mS value came about from a bit of trial and error, comparing a Reason rendered wav file with a Live midi clip controlling redrum. I have no idea why -10mS should be used when my overall latency is 13mS [6.5 + 6.5]. However, it seems to work well enough.

The only problem is using Reason's own sequencer [or even REX's preview function] at the same time as Live. Its midi data is not pushed forward and is out of sync with Live.

It would be nice if Live could recognise Rewire as being a special case of audio in and would compensate accordingly.

drez · Post by **drez** » Fri Dec 02, 2005 3:01 pm

Synthbuilder wrote:I have been looking into this a bit more.

Firstly I got a reply from Ableton who confirmed that the rewire input is indeed delayed. I guess one would expect this since rewire is piped into Live as if it were an external audio signal. Thus is therefore bound by the latency problem.

My workaround appears to be fairly straightforward. Every midi channel that controls any Reason synth is predelayed by -10mS, not -13mS as previously stated. The rewire inputs to Live are left at the default 0mS delay. This allows the midi to be in sync with the audio that Live is playing.

I found that delaying the audio channels by 10mS is no good because the metronome is out of kilter with what is being replayed. So you have to predelay the midi.

Note: the -10mS value came about from a bit of trial and error, comparing a Reason rendered wav file with a Live midi clip controlling redrum. I have no idea why -10mS should be used when my overall latency is 13mS [6.5 + 6.5]. However, it seems to work well enough.

The only problem is using Reason's own sequencer [or even REX's preview function] at the same time as Live. Its midi data is not pushed forward and is out of sync with Live.

It would be nice if Live could recognise Rewire as being a special case of audio in and would compensate accordingly.

Thanks for the workaround! This will help out alot. What's odd is that I don't remember even realizing it in Live4.

Synthbuilder · Post by **Synthbuilder** » Fri Dec 02, 2005 3:30 pm

The plot thickens and I am getting really really confused.

Setting predelays to any VSTi midi channel also affects all the rewire channels. Without rewire the track delays work as they should, that is individual tracks can be delayed or predelayed. But soon as rewire is connected to Live, then the problems start to occur.

So you can set any midi track delay to anything but the track delay on a VSTi channel will affect the track delay on a rewire channel. ie you cannot set individual track delays on rewire outputs!! Well, at least any track delay you do set doesn't appear to have a true relation with the actual delay heard.

So my workwaround is not entirely a fix at all.

Maybe the best thing is to turn off PDC...

I have contacted Ableton to see what their take is on this rather serious matter.

Tony

Kala · Post by **Kala** » Mon Dec 05, 2005 10:18 am

What a pitty!
I thought that I found my optimum composing and jamming set-up with my new iMac G5, M-Audio Ozonic, LIVE 5, REASON 3, VSTs for rhythms like Groove Agent, GURU, and my hardware keyboards via midisport.

But yesterday I experienced the same phenomenon described in this post. While the VSTs, LIVE, and my synth hardware were in perfect sync, a REASON bass-line that I triggered via a LIVE-Midi clip was out of tempo.

I could match it by adjusting track delay of the Audio-in (from Reason) somewhere between -10 and -14 ms. Then it seemed to fit again...
Live's global latency was 14 ms (7+7), 256 samples.

What is weired: my impression is that it's not a constant latency value for every REASON / LIVE / VST song that I record...I compared it to previous recordings in similar set-up. Some have no delay at all...some have a bigger delay than -14 ms...but this is really subjective.

Any help on the horizon? I really like LIVE 5 and I really like REASON 3...
especially for composing something with my synth-hardware and then switching to REASON soft-synth/sampler when sitting on the couch..

Do we have to wait for a REASON-VST?

Thanks,
Daniel

noou · Post by **noou** » Tue Dec 06, 2005 10:46 pm

drez wrote: Thanks for the workaround! This will help out alot. What's odd is that I don't remember even realizing it in Live4.

I really found the issue when opening a Live4 project under Live5. I never owned Live4 but I continued working on a set previously started from a mate. He never experienced any delay in Live4! I heard the very same project on his computer and all was in sync!
Why going onto Live5 we've lost that?
Did you ever found this same problem in Live4? I'm becoming crazy?

diverdee · Post by **diverdee** » Wed Dec 07, 2005 11:02 pm

I will add a bump here - as this & the midi timing issue appear to be issues which are crucial for anyone wanting to easily achieve tight timing whilst using rewire applications or vsti's.

sungwei · Post by **sungwei** » Mon Dec 12, 2005 5:48 am

We're having the same problem over here. Although ours was working from the get go. This problem just recently occured. I have not tried setting the delays yet on the tracks. The worse part is all of the delay is captured when you render or resample the track. I don't understand why the problem would come out of nowhere. This happened in new tracks and old tracks. This happened to tracks with and without Wave or other plug ins. One thing I did notice is on one track I removed the Trilogy VSTi and it resolved the issue. But in other tracks where there is no Trilogy or plug ins used it is delayed. It's weird.

Kala · Post by **Kala** » Mon Dec 12, 2005 7:32 am

Reading this comment by the Abes, I understand the connection between VSTs used in a song and latency compensation -> Rewire delay:

http://www.ableton.com/forum/viewtopic. ... highlight=

The question remains: why was this comming up with Live5?
(or did anybody observe this in Live4??)

Regards,
Daniel

Post by **Alex** » Mon Dec 12, 2005 2:23 pm

Hi Synthbuilder,

my teammate Andreas replied to a similar question in this thread:
http://www.ableton.com/forum/viewtopic.php?t=25534

regards,
/Alex

Synthbuilder · Post by **Synthbuilder** » Mon Dec 12, 2005 2:48 pm

Thanks for looking into this Alex. Unfortunately, the track delay setting appears to be broken in 5.02 and 5.03betas if you need rewire. You may have seen my other posts in the forum regarding this.

http://www.ableton.com/forum/viewtopic.php?t=30691

In summary any negative track delay set up on any other track [midi or audio] affects the track delay on any rewire inputs. Also, there seems to be no relation between a delay set up in one set and another. That is some sets are more affected than others. In other words its nigh on impossible to sync Reason with Live with PDC on. Switching PDC off makes things playback more in sync.

Cheers,

Tony

Post by **Alex** » Mon Dec 12, 2005 2:52 pm

Synthbuilder,

In other words its nigh on impossible to sync Reason with Live with PDC on. Switching PDC off makes things playback more in sync.

Yes, that is right. This is a limitation of the current behavior of PDC we hope to improve in a future release of Live.

regards,
/Alex

Latency issues with Rewire

Latency issues with Rewire

Re: Latency issues with Rewire

Same thing with me ...

Connection between VST and Rewire delay