On Sun, 2011-06-05 at 23:09 +0200, Hartmut Noack wrote: > Am 05.06.2011 20:05, schrieb Ralf Mardorf: > > On Sun, 2011-06-05 at 19:39 +0200, Hartmut Noack wrote: > >> Am 05.06.2011 11:00, schrieb Robert Klaar: > >>> What happens if you set the frames/period settings higher? I have similar > >>> setup and can't get it to run on any lower than 1024 frames(if I want to > >>> avoid xruns), but then I've set the sample rate to 48000. I've never > >>> noticed > >>> any problems with the latency, it's at 46 or something now but I can't > >>> hear > >>> any difference between this and something lower, can you? .) > >> > >> Yes I can. > >> > >> I work with musicians and my experience is: > >> > >> lower than 5ms: nobody noticed that in comparison with 10ms > >> > >> 5-10ms: everything fine, no complaints > >> > >> around 16ms: all but some singers realise that something is going on, > >> faces grow longer, some demand changes. > > > > Ok, so we do agree that the Haas-Effect has nothing to do with audible > > delay for a groove, but I don't agree that lower than 5 seconds isn't > > audible. It is, regarding to a groove, e.g. played by a MIDI keyboard, > > controlling a soft-synth. It's annoying, but a constant delay is > > something a musician is able to handle, anyway, I do agree that up to 11 > > ms are 'quasi' inaudible. Pipe organs might have a delay up to 30 or 50 > > ms, I dunno, but musicians are able to play such an instrument. Just > > jitter is a no go, especially for this case ... > > > >> > >> For very big projects on lesser machines I run Jack with 30 or more ms > >> latency. It is OK for mixing/editing etc but I do not record any > >> overdubs with such settings. > > > > ... > > > > What's the problem with overdubs? You listen to the delayed sound, but > > for you it isn't delayed, you play in real-time without monitoring the > > delayed recording and the latency compensation moves it to the correct > > time. > > The problem is, that I record most of the overdubs using software, that > either generates or processes the signal.
Ok, for generated sound there is a latency issue. I just wondered, because you wrote about vocalist. Regarding to issues for singers, the monitoring should be without processing. > > Hence latency has no impact, but jitter would have, because jitter > > can't be auto-compensated. > > I use to record overdubs by playing instruments/voice so we would talk > about audio-jitter here. > > That would be: > > If I record the very same audio-signal from a Jack-output to a track in > Ardour several times it would be predictable, that the recordings start > to be/sound affected by such jitter-effects. > > How many generations do you estimate until such effects would become > audible? First generation, not as timing issue, but as phasing. This phasing won't cause a phasing effect, but less transparent sound. > >> I remember I did some years ago but it > >> really was not fun and the results where not as good as they could have > >> been. > > > > I don't understand? What happened? Latency only will become an issue, if > > it isn't a fix delay, or if you need to monitor the delayed output, e.g. > > for soft synth, > > exactly that, see above. > > > apart from that latency has no influence. > > > >> Any recent Linux sould allow settings for 16ms or lower for normal load. > > > > It's related to the hardware and work flow. ElCheapo cards might be able > > to keep such latency when Periods/Buffer are set ex 3, jitter than might > > be another issue ;). > > Yes, it is known, that cheap chipsets almost never provide exactly the > samplerate they are set up with and that they can drift. I didn't know that, but I do believe that this is true, because ... > To be honest: I do not hear any effects of that. ... I do hear a bad sound quality for most sound cards and I guess it's regarding to (audio , not midi ;) jitter and sync issues. > Please correct me, if I am wrong: the soundcard is only the > player/recorder. Jack processes the signal internally whithout using or > even needing the sound card at all. Thus it is no great suprise, that > material, that I process while Jack runs with a HDA-chipset fails to > degenerate and sounds not better or worse if I play them the other day > on a envy24-chipset or a Presonus Firebox. > > I do hear the differences of a ADC/DAC for 30 Euros compared with a > converter for 30 Cents ;-) > > > > >> If it does not, I try the standard-procedures to fix it, if this does > >> not help I switch the distro. > > > > And first of all, don't care that much about latency, because latency > > very seldom is an issue, just jitter could become an issue. > > I agree, that audible jitter would be an absolute show-stopper. > > Anyway I never heared such effects in any recordings I made in the last > 7-8 years. I only had audible effects in the form of xruns and in > test-scenarios with insane settings or with alpha-software or a severely > misconfigured system. Yes, glitches are bad, but IMO (excepted for computer generated sound) latency isn't important, so it should be possible to increase the latency to get no glitches. Btw. I completely agree that when playing a virtual synth, a latency around 10-11 msec is ok and ElCheapo cards already enable such latencies. If not, something is broken. Unfortunately hardware and Linux always cause issues. I bought a RME HDSPe AIO and will return it to the dealer this week, because it's a PITA to get the card working. At the moment I've got no idea what sound card I should buy instead :(. I'm using Linux only, but good sound cards seems to be supported for Mac only, resp. sometimes for Windows too. I'm not fine with the sound quality of M-Audio and similar gear. Ok, you're right regarding to latency, I misunderstood what you've written. Anyway, as long as people avoid to play a soft synth by a MIDI keyboard or they avoid to monitor processing, latency isn't an issue, at least Ardour will compensate latency. Regards, Ralf -- Ubuntu-Studio-users mailing list [email protected] Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-studio-users
