Latency question...yet again

    This isnt as much of a problem as a general question. I am running the os4 beta and I have been working on a track. I run the audio to the analog outputs and put the virus in live mode. Now, there was always a latency adjustment to be made doing this. To be exact I had to offset my midi notes by +1370 samples. I tried to play the track recently and the offset was no longer needed. Live mode basically put me right at 0 samples offset. Was this adjusted in os4 release? I assume the offset should always be the same regardless of how many channels have a patch loaded in, or how many plug ins I am using in my host.

    Zitat von creap

    This isnt as much of a problem as a general question. I am running the os4 beta and I have been working on a track. I run the audio to the analog outputs and put the virus in live mode. Now, there was always a latency adjustment to be made doing this. To be exact I had to offset my midi notes by +1370 samples. I tried to play the track recently and the offset was no longer needed. Live mode basically put me right at 0 samples offset. Was this adjusted in os4 release? I assume the offset should always be the same regardless of how many channels have a patch loaded in, or how many plug ins I am using in my host.

    we didn't fix anything specific to the live mode or latency compensation is OS4 (at least not that i can remember). this offset of +1370 samples would compensate for roughly the latency the virus announces in live mode, in other words, live mode didn't work work as expected or the virus was not delay compensated at all. what host are you using or used at this time?


    best, marc

    Using Pro Tools 8.0.3 LE on mac os 10.5.8. I have tried using audio delay compensation and just settled on using a midi offset. I just don't understand why all of a sudden the delay would change on the virus. I added another patch to the virus but it is only actually playing one patch, so its not like i overloaded it or anything.

    Zitat von creap

    Using Pro Tools 8.0.3 LE on mac os 10.5.8. I have tried using audio delay compensation and just settled on using a midi offset. I just don't understand why all of a sudden the delay would change on the virus. I added another patch to the virus but it is only actually playing one patch, so its not like i overloaded it or anything.

    LE doesn't delay compensate. in other words, when you switch on live mode (or switch it off) you will automatically destroy the timing. say you've compensated against the latency introduced when live mode is on and you switch it off, all the tracks will be not in time. honestly, using a host without automatic delay compensation, you will have a hard time to keep things in sync.


    best, marc

    Thats not the point, I have automatic delay compensation plug ins, but the difference here is this. My virus is ALWAYS in Live mode, and the delay changed. When at first it was in time with 1370 offset, after awhile an offset of 0 kept it in time. It is still in Live mode, so why has the timing changed?


    I am also curious, since auto delay comp depends on plug in reporting, pro tools reports the delay of the virus in live mode as 522 samples, which is incorrect, so how would that really help me?

    Zitat von creap

    Thats not the point, I have automatic delay compensation plug ins, but the difference here is this. My virus is ALWAYS in Live mode, and the delay changed. When at first it was in time with 1370 offset, after awhile an offset of 0 kept it in time. It is still in Live mode, so why has the timing changed?


    I am also curious, since auto delay comp depends on plug in reporting, pro tools reports the delay of the virus in live mode as 522 samples, which is incorrect, so how would that really help me?

    i didn't hear of automatic delay compensation plug-ins so far. what's that?


    marc

    I use mellowmuse ATA. While its not an AUTOMATIC delay compensation, in my opinion it does basically the same thing but more accurately. It sends a ping over the audio channel and measures the response time and then automatically delays the tracks to fit in time with whatever they need to be. It is also nice because it can compensate for any outboard gear you may be using, like a compressor or effects rack unit. Change some settings, just ping again and it automatically adjusts. This does not work on the virus since the virus is not a plug in where audio passes through it. Most of my VI's have near zero latency so I dont really need to compensate them, unless I am compensating them against a channel with alot of effects on it, but then ATA can do that for me.


    Dont get me wrong, I wish digidesign and avid would wake up and fix all the stupid restrictions on PT LE, like no ADC. But I still argue that ADC is not a universal fix since ADC depends on plug-ins reporting delay correctly (which they dont always do).


    Like I said, in Live mode PT reads the delay from the virus plug in as 522 samples....which is way off. I don't know if that reporting would change in PT HD.


    I dont care that I have to set a midi offset, Everything has synced OK so far, but now all of a sudden my latency has changed, and I haven't really changed anything. I do still get weird pitch bend glitches and clicks and other fun stuff from time to time, I just dont think the virus was made for PT LE. I really need to experiment some more with heavy layered tracks on the virus and see what happens.

    live mode will change the latency and other things might change it as well, in fact, even hosts change the latency depending on the situation. that will not work well. it might work for an insert plug-in, for e.g. routing an analog compressor into the digital signal chain but it will not work on instruments.

    Zitat

    But I still argue that ADC is not a universal fix since ADC depends on plug-ins reporting delay correctly (which they dont always do).

    i can't comment on other products but as for the virus, we will fix bugs related to reporting a wrong latency.

    Zitat

    Like I said, in Live mode PT reads the delay from the virus plug in as 522 samples

    might be, the latency of the live mode depends on the buffer size of your audio buffer. i know i'm repeating myself here but let me just say again that there is good reason why we don not recommend live mode for non playback situations.


    marc

    But without live mode, I get non synced arps, clicks and pops and a whole host of problems. I simply CANNOT record the virus in pro tools LE without live mode. Honestly the most stable solution for me is to just use midi cables and audio out. I get perfect sync and no audio distortion at all. I hate this approach because I like to have patches reload with a project and I like the easy to use interface. Obviously the virus uses some different clock features when running on midi vs running off usb.


    Every day I question why I went with pro tools and spent all this money on a 003 factory setup when I could have just got a nice firewire interface and some universal controller and used whatever DAW I wanted. My frustration with PT aside, I just want to make music, and the virus (among other things) fights me every step of the way.

    Hey creap


    first off, That was very interesting what you where talking about, the delay compensation system you use, very smart indeed, never knew that existed but it sounds very useful for people not using Protools HD.


    Second, I am soooo with you about Protools/Avid. I have M-powered, and that's even more limiting than LE (no bloody complete toolkit, bastards)


    Finally, I understand it's frustrating to end up with a DAW that doesn't perfectly fit your purpose, and I wouldn't even think about programming Midi with Protools. I feel it's just not made for that, while I don't really like using anything else for audio (especially in post-production).


    But may I suggest Logic 9?


    Although you may not be able to use the control surface functions of the 003 (and you never know, some clever geek might have figured a way to translate the Didi control interface to be used by other DAWs), you can still use it as an audio interface, and a rather good one at that... The added bonus is that you'll be able to use the Virus TI plugin (which works nicely with Logic).


    Then you can just bounce everything and mix in protools if you prefer (I know I do)


    I'm sure you can find a good deal on a full copy of Logic 9 somewhere... ;)

    Zitat von creap

    But without live mode, I get non synced arps, clicks and pops and a whole host of problems. I simply CANNOT record the virus in pro tools LE without live mode. Honestly the most stable solution for me is to just use midi cables and audio out. I get perfect sync and no audio distortion at all. I hate this approach because I like to have patches reload with a project and I like the easy to use interface. Obviously the virus uses some different clock features when running on midi vs running off usb.


    Every day I question why I went with pro tools and spent all this money on a 003 factory setup when I could have just got a nice firewire interface and some universal controller and used whatever DAW I wanted. My frustration with PT aside, I just want to make music, and the virus (among other things) fights me every step of the way.

    i guess that happens with the tutorial song as well? why don't you send me a project, i have an mbox micro in the office and i could try to get a close to your setup as possible and let you know about the outcome. one real question though. in protools HD you can tell RTAS to use less CPU cores than the maximum. if you reduce the cores to, say 2 for instance, does that make a difference?


    also here's some background for you guys listening: the live mode we really did for hosts which do not support some specifications or feature implementations total integration needs to run smooth. at the point in time we did this, ableton live was one of the most prominent examples because otherwise playing the virus with virus control would simply result in notes during recording would be really late (playback was always fine). the live mode has one big disadvantage though: in difference to its being disabled, the notes would not be sample accurate and possibly even slightly less accurate than normal midi. it is a compromise with the benefit that you don't deal with latency during recording your performance. it was never intended to cure anything else.
    click and pops usually happen for four reasons:
    - the host is totally overloaded and cannot cope anymore
    - the usb transmission doesn't work as intended and data packages get "lost" or really late in time (this is where distortion can come in)
    - the virus' mixer overloads (red in digital means damaged data, not added saturation like in the analogue world)
    - software setup problems
    by the way, i'm happy that this conversation happens right now because most of the time i see those threads, it appears that they are there for venting off instead of trying to solve it.
    have a good weekend


    marc

    hmm I hope I'm posting this in the right topic , but I'm having huge problems with this live mode feature. I told it in other topics, but if I don't enable it: the arps are completely desynced, play unstable and play in front of all other cubase events. If I enable live mode it's somehow more stable but it can sometimes happen that the first arp note plays slightly in front of the first cubase metronome click.


    So enabling live mode for me is actually the way to make the arpegio's tight. Unless I need to cope with another problem in my DAW. The particular project i'm working on is so heavy that I have to put my soundcard latency to 232ms, just to avoid all cpu overload pops and sound cuttofs on some other plugins.


    The virus doesn't seem to handle this high latency very well as the arp will play as bad without live mode than it would play if live mode is enabled. Even with the live button off, at 23ms the virus sounds very unstable and messy. I tried to set the virus driver's setting to both "normal" , changed back to hammerfall DSP, but still the virus continues to play the arps unstable. The problem is I can't freeze the other plugins because it' doesn"t like "non realtime" freezes and will result in cut off played sounds and pops.


    The only thing I can think of now is to first bounce the heavy sample plugins like play to disk, freeze and unloadd them sepparately and then then trying to mix.

    Yeah it's something like that. 23ms is exactly 1024 samples. The big problem is that even when I set the latency to 6 or 12ms and try to bounce the virus in solo (to get it out of the equasion) i still have pops and crackles because of cpu overloads. Because i've so much compression and verb plugins loaded and not to mention the eastwest play plugins that are loaded : it's not possible for me to export this song anyway. The extra catch 22 trap is that when I freeze the PLAY instruments, their release trails start cutting off cause they can't handle non real time freezes.


    Only thing I can still try is try to start by bouncing play plugins solo track per track, then remove them so they are out of the way. Then bounce the virus plugin and remove it. Then freeze all NI plugins. I think at that point the system should be stable enough to export the song without overloads, unsynced arpeggios, cracks & pops :)


    The problem with that is that it causes so much workload and clutter. It's nicer to just be able to export a song in one go cause I know myself. if I hear one little error i'd have to unfreeze everything. So I end up with 4 versions of the same projects. unfrozen, partially frozen, frozen final ...... :P

    Quoted creap:
    "But without live mode, I get non synced arps, clicks and pops and a whole host of problems."
    - It seems this delay you talking about is in every case the same to me, the systems are not able to sync in a specific way. I still try to work on it.



    Quoted Marc:
    "in protools HD you can tell RTAS to use less CPU cores than the maximum. if you reduce the cores to, say 2 for instance, does that make a difference?"
    - With this feature in HD & LE you can choose how many cores of your CPU will handle the processing power for RTAS Plugins. For example: 2 cores will primary receive RTAS informations, and the 2 other cores are assigned to all other applications. (OS, PT, and so on...)


    I was tried to setup virus to 1 core, because I thought the sample/phase accuration could may be instable in LE. multithreading works 100% with virus and RTAS.
    Its more a hard-RTAS bug in LE and Windows. Never heared a problem from MacOS in combination with the 003 Rack.



    Marc, if you try to solve the problem with your M-Box, let us know whats going on.
    The M-Box could work better, but remember it's not the same hardware or may not the same RTAS source like the 003 Rack.
    My System: XP, 003 Rack+ LE 8.0.3 - TIOS 4+



    Quoted Marc:


    "click and pops usually happen for four reasons:
    the host is totally overloaded and cannot cope anymore"
    - PT LE is not overloaded, RTAS CPU load is at 1%


    "the usb transmission doesn't work as intended and data packages get "lost" or really late in time (this is where distortion can come in)"
    - that sounds more like the sync/latency problem


    "the virus' mixer overloads (red in digital means damaged data, not added saturation like in the analogue world)"
    - the signal from virus USB to PT is not overloaded


    "software setup problems"
    - PT is up to date and all RTAS plugins could be compensated manually



    Thanx for tuning in.