... or: "the power of the darkside" ... or: "how i hope to learn to stop clicking and love live processing" ... or: "yet another frequently annoying question"
morning all,
my burning questions, to any and all mobile pd users who feel inclined to respond, are:
(A) what is the lowest (stable) latency you can achieve with pd and the laptop of your choice?
and
(B) is the onboard soundcard on said laptop tolerable (A/D-D/A sync, general quality, etc.)? [i realize it probably won't be great; i just can't afford a hammerfall, my quattro is basically crap, and the adc on my terratec usb is thoroughly unsatisfying]
Motivation: as avid readers of pd-dev may recall, my trusty old laptop was stolen last week (*schneef*), which is all very annoying etc. (fingerprint powder is a right $/%&! to clean off of a white windowsill), but does at least give me the chance to improve on some of its less desirable qualities when choosing its replacement, so yes, this is one of those "what's the best laptop for running pd" mails (profuse apologies; feel free to flame me, but we haven't had one on the list in at least a month now ;-)
so far, my favorite linux candidates are ibm(lenovo) [older T or newer R] or dell, but upon consideration, i realize that the dark side of the force (Apple MacBook(intel)/OS-X) does indeed have a certain allure. the specs are pretty much identical, but the dark side does have a growing attraction as i become older and lazier... so: anyone out there with direct experience of both mactel & linux willing to commit on the issue of audio performance?
marmosets, Bryan
Apple puts good audio hardware in their laptops. I can get 14ms of latency on Mac OS X with Pd without really trying (I just set it to 14ms). I can get down to 11ms if I don't mind clicks when I operate the menus and switch to other applications.
I think that if you really want to get down to something like 2-3ms, then you'll have to work at it, and you'll probably be better of with a Debian-based system or maybe PlanetCCRMA.
.hc
On Dec 15, 2006, at 2:18 PM, Bryan Jurish wrote:
... or: "the power of the darkside" ... or: "how i hope to learn to stop clicking and love live processing" ... or: "yet another frequently annoying question"
morning all,
my burning questions, to any and all mobile pd users who feel inclined to respond, are:
(A) what is the lowest (stable) latency you can achieve with pd and the laptop of your choice?
and
(B) is the onboard soundcard on said laptop tolerable (A/D-D/A sync, general quality, etc.)? [i realize it probably won't be great; i just can't afford a hammerfall, my quattro is basically crap, and the adc on my terratec usb is thoroughly unsatisfying]
Motivation: as avid readers of pd-dev may recall, my trusty old laptop was stolen last week (*schneef*), which is all very annoying etc. (fingerprint powder is a right $/%&! to clean off of a white windowsill), but does at least give me the chance to improve on some of its less desirable qualities when choosing its replacement, so yes, this is one of those "what's the best laptop for running pd" mails (profuse apologies; feel free to flame me, but we haven't had one on the list in at least a month now ;-)
so far, my favorite linux candidates are ibm(lenovo) [older T or newer R] or dell, but upon consideration, i realize that the dark side of the force (Apple MacBook(intel)/OS-X) does indeed have a certain allure. the specs are pretty much identical, but the dark side does have a growing attraction as i become older and lazier... so: anyone out there with direct experience of both mactel & linux willing to commit on the issue of audio performance?
marmosets, Bryan
-- Bryan Jurish "There is *always* one more bug." jurish@ling.uni-potsdam.de -Lubarsky's Law of Cybernetic Entomology
PD-ot mailing list PD-ot@iem.at http://lists.puredata.info/listinfo/pd-ot
------------------------------------------------------------------------
Access to computers should be unlimited and total. - the hacker ethic
Now that Apple went Intel, why not just get one and partition the drive to run OS X, GNU/Linux, and (God forbid) Windows? You'd be unstoppable.
~Kyle
On 12/15/06, Hans-Christoph Steiner hans@eds.org wrote:
Apple puts good audio hardware in their laptops. I can get 14ms of latency on Mac OS X with Pd without really trying (I just set it to 14ms). I can get down to 11ms if I don't mind clicks when I operate the menus and switch to other applications.
I think that if you really want to get down to something like 2-3ms, then you'll have to work at it, and you'll probably be better of with a Debian-based system or maybe PlanetCCRMA.
.hc
On Dec 15, 2006, at 2:18 PM, Bryan Jurish wrote:
... or: "the power of the darkside" ... or: "how i hope to learn to stop clicking and love live processing" ... or: "yet another frequently annoying question"
morning all,
my burning questions, to any and all mobile pd users who feel inclined to respond, are:
(A) what is the lowest (stable) latency you can achieve with pd and the laptop of your choice?
and
(B) is the onboard soundcard on said laptop tolerable (A/D-D/A sync, general quality, etc.)? [i realize it probably won't be great; i just can't afford a hammerfall, my quattro is basically crap, and the adc on my terratec usb is thoroughly unsatisfying]
Motivation: as avid readers of pd-dev may recall, my trusty old laptop was stolen last week (*schneef*), which is all very annoying etc. (fingerprint powder is a right $/%&! to clean off of a white windowsill), but does at least give me the chance to improve on some of its less desirable qualities when choosing its replacement, so yes, this is one of those "what's the best laptop for running pd" mails (profuse apologies; feel free to flame me, but we haven't had one on the list in at least a month now ;-)
so far, my favorite linux candidates are ibm(lenovo) [older T or newer R] or dell, but upon consideration, i realize that the dark side of the force (Apple MacBook(intel)/OS-X) does indeed have a certain allure. the specs are pretty much identical, but the dark side does have a growing attraction as i become older and lazier... so: anyone out there with direct experience of both mactel & linux willing to commit on the issue of audio performance?
marmosets, Bryan
-- Bryan Jurish "There is *always* one more bug." jurish@ling.uni-potsdam.de -Lubarsky's Law of Cybernetic Entomology
PD-ot mailing list PD-ot@iem.at http://lists.puredata.info/listinfo/pd-ot
Access to computers should be unlimited and total. - the hacker ethic
PD-ot mailing list PD-ot@iem.at http://lists.puredata.info/listinfo/pd-ot
Hans-Christoph Steiner wrote:
Apple puts good audio hardware in their laptops. I can get 14ms of latency on Mac OS X with Pd without really trying (I just set it to 14ms). I can get down to 11ms if I don't mind clicks when I operate the menus and switch to other applications.
as always when it comes to latency and people tell numbers, i have to ask my question: have you measured this? how? or was it just "putting a number somewhere and assuming that it's the real latency"? how much load do your settings allow?
mg-asdr IOhannes
it is easy to measure: use an external sound source and recording equipment. lead one channel through your pd device and pd patch, the other directly into your recording device. the time differentce between the two is the latency. marius.
IOhannes m zmoelnig wrote:
Hans-Christoph Steiner wrote:
Apple puts good audio hardware in their laptops. I can get 14ms of latency on Mac OS X with Pd without really trying (I just set it to 14ms). I can get down to 11ms if I don't mind clicks when I operate the menus and switch to other applications.
as always when it comes to latency and people tell numbers, i have to ask my question: have you measured this? how? or was it just "putting a number somewhere and assuming that it's the real latency"? how much load do your settings allow?
mg-asdr IOhannes
PD-ot mailing list PD-ot@iem.at http://lists.puredata.info/listinfo/pd-ot
On Dec 16, 2006, at 8:38 AM, IOhannes m zmoelnig wrote:
Hans-Christoph Steiner wrote:
Apple puts good audio hardware in their laptops. I can get 14ms of latency on Mac OS X with Pd without really trying (I just set it to 14ms). I can get down to 11ms if I don't mind clicks when I operate the menus and switch to other applications.
as always when it comes to latency and people tell numbers, i have to ask my question: have you measured this? how? or was it just "putting a number somewhere and assuming that it's the real latency"? how much load do your settings allow?
Yes, its true, I am too lazy to do an actual measurement. I am just talking about the buffer setting. For what I do, I don't really need much lower.
And always, when talking about latency, I feel the need to point out the speed of sound: 340 m/s or .34 m/ms. So if your speakers are 2m away from you, that's 6ms of latency. You could spend days tweaking your machine to get 3ms less latency, or you could move 1m closer to your speakers. Puts things into perspective...
.hc
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News is what people want to keep hidden and everything else is publicity. - Bill Moyers
On 2006-12-16 19:02:08, Hans-Christoph Steiner hans@eds.org appears to have written:
And always, when talking about latency, I feel the need to point out the speed of sound: 340 m/s or .34 m/ms. So if your speakers are 2m away from you, that's 6ms of latency. You could spend days tweaking your machine to get 3ms less latency, or you could move 1m closer to your speakers. Puts things into perspective...
indeed 'tis true. but 5ms vs. 10ms makes a major subjective/perceptual difference if we're talking about playing an electro-acoustic instrument in and getting a munged signal out...
marmosets, Bryan
On Sat, 2006-12-16 at 19:14 +0100, Bryan Jurish wrote:
On 2006-12-16 19:02:08, Hans-Christoph Steiner hans@eds.org appears to have written:
And always, when talking about latency, I feel the need to point out the speed of sound: 340 m/s or .34 m/ms. So if your speakers are 2m away from you, that's 6ms of latency. You could spend days tweaking your machine to get 3ms less latency, or you could move 1m closer to your speakers. Puts things into perspective...
indeed 'tis true. but 5ms vs. 10ms makes a major subjective/perceptual difference if we're talking about playing an electro-acoustic instrument in and getting a munged signal out...
a latency of 25ms could be used to simulate some early reflections ;)
-- tim@klingt.org ICQ: 96771783 http://www.mokabar.tk
The composer makes plans, music laughs. Morton Feldman
On Dec 16, 2006, at 1:14 PM, Bryan Jurish wrote:
On 2006-12-16 19:02:08, Hans-Christoph Steiner hans@eds.org appears to have written:
And always, when talking about latency, I feel the need to point out the speed of sound: 340 m/s or .34 m/ms. So if your speakers are 2m away from you, that's 6ms of latency. You could spend days tweaking your machine to get 3ms less latency, or you could move 1m closer to your speakers. Puts things into perspective...
indeed 'tis true. but 5ms vs. 10ms makes a major subjective/ perceptual difference if we're talking about playing an electro- acoustic instrument in and getting a munged signal out...
Do you have any references on that? I think it could be perseptable to a very experienced musician, but I don't think there is a major effect. From the studies that I have read, jitter has a much larger affect than latency in terms of affecting performance. (I need to find some references myself... ;)
Also important to note is that conscious processing of sound in the brain is actually quite slow. Yes, the ear can perceive changes on the order of 0.05ms (20,000Hz), but your brain is made consciously aware of these changes at a much slower rate. You can hear an example of this using a oscillating frequency. A slow change in the frequency of a tone is perceived as vibrato: you can consciously hear the wavering pitch. As that change in frequency becomes faster, you can no longer consciously hear the wavering pitch. Instead you perceive a steady tone. I attached a patch to illustrate this.
Performers are actually quite adept at adjusting to latency. Just think of an orchestra or choir: there could be 20ms or more of latency from one side of the stage to the other, yet its not hard for a moderately trained group to handle it. Another key factor in performance is physical feedback, which has a much faster feedback loop that the audio system. Trained musicians can feel a mistake and correct it long before the sounds are consciously perceived. (I first saw that in print on one of Miller's papers http:// crca.ucsd.edu/~msp/Publications/icmc93.ps)
One realm were I could see that latency would be important would be when measuring response time to a stimulus, like in a psychological experiment. But even still, as long as the latency is steady (i.e. low jitter), the latency is not a big deal.
.hc
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If nature has made any one thing less susceptible than all others of exclusive property, it is the action of the thinking power called an idea, which an individual may exclusively possess as long as he keeps it to himself; but the moment it is divulged, it forces itself into the possession of everyone, and the receiver cannot dispossess himself of it. - Thomas Jefferson
On 2006-12-16 20:44:22, Hans-Christoph Steiner hans@eds.org appears to have written:
On Dec 16, 2006, at 1:14 PM, Bryan Jurish wrote:
On 2006-12-16 19:02:08, Hans-Christoph Steiner hans@eds.org appears to have written:
And always, when talking about latency, I feel the need to point out the speed of sound: 340 m/s or .34 m/ms. So if your speakers are 2m away from you, that's 6ms of latency. You could spend days tweaking your machine to get 3ms less latency, or you could move 1m closer to your speakers. Puts things into perspective...
indeed 'tis true. but 5ms vs. 10ms makes a major subjective/perceptual difference if we're talking about playing an electro-acoustic instrument in and getting a munged signal out...
Do you have any references on that? I think it could be perseptable to a very experienced musician, but I don't think there is a major effect.
well, i wouldn't call myself a *very* experienced musician, but plugging a guitar into the computer and just running the signal through a simple [adc~]->[dac~] in pd with 10ms reported latency (latency.pd gives 10-11ms) is easily detectable, it being a pain in the wazoo to play (probably has to do with the fact that i am at best only a mediocre guitarist, but that's not the point :-/). also, 10ms is roughly the minimal "willed action -> muscular implementation" latency on your average homo sapiens architecture (get a stopwatch, try it out ;-)
From the studies that I have read, jitter has a much larger affect than latency in terms of affecting performance. (I need to find some references myself... ;)
i think you're right there. i know Reinhold Kliegl and Ralf-Thomas Krampe have done a lot of rhythm perception studies in Potsdam, with professional musicians, amateur musicians, and non-musicians as subjects, and the pros pretty much blew everyone else away precision-wise.
Performers are actually quite adept at adjusting to latency. Just think of an orchestra or choir: there could be 20ms or more of latency from one side of the stage to the other, yet its not hard
for > a moderately trained group to handle it.
as a former orchestra inmate myself, i seem to recall concentrating mostly on keeping a constant time myself -- the "big picture" ("big sound?") just isn't available to a 3rd tier 2nd violinist -- i went by the conductor's tempo and the momentum i got from those around me: the only real trick was keeping it constant, but that's "just" training: hence perhaps the jitter-related problems even for the pros...
Another key factor in performance is physical feedback, which has a much faster feedback loop that the audio system. Trained musicians can feel a mistake and correct it long before the sounds are consciously perceived. (I first saw that in print on one of Miller's papers http://crca.ucsd.edu/~msp/Publications/icmc93.ps)
One realm were I could see that latency would be important would be when measuring response time to a stimulus, like in a psychological experiment. But even still, as long as the latency is steady (i.e. low jitter), the latency is not a big deal.
it can certainly be compensated for if it is known, but for me as a guitarist, it amounts essentially to learning an entirely new style, since i'm just plain not good enough to compensate before the glitches become painfully audible...
marmosets, Bryan
On Dec 16, 2006, at 1:14 PM, Bryan Jurish wrote:
On 2006-12-16 19:02:08, Hans-Christoph Steiner hans@eds.org appears to have written:
And always, when talking about latency, I feel the need to point out the speed of sound: 340 m/s or .34 m/ms. So if your speakers are 2m away from you, that's 6ms of latency. You could spend days tweaking your machine to get 3ms less latency, or you could move 1m closer to your speakers. Puts things into perspective...
indeed 'tis true. but 5ms vs. 10ms makes a major subjective/ perceptual difference if we're talking about playing an electro- acoustic instrument in and getting a munged signal out...
Now some promised references:
---------------------------------------------
"As already noted in 3.1, the precedence effect says that sounds are perceived as coming from a single source when they occur within 25-35 ms time window (Haas, 1949). Later research has suggested that we can subconsciously perceive latencies below 10 ms, but in musical instrument performance context latency tolerance can be even higher than 50 ms. Chew et al. (2004) have studied duo performances, and in four-hand piano experiment they have found that delays below 50 ms were generally considered tolerable, and that when local delay was introduced, the tolerance increased to 65 ms.
They also concluded that latency tolerance is dependant on tempo (slower tempo equals higher tolerance), and on instrumentation. For example, if a synthesizer pad type sound is used in ensemble performance, the musician has to anticipate chord changes so that slow attack is matched with the song tempo (corresponding latencies of several hundred milliseconds), whereas transient sounds result lower latency tolerance levels. Musical genre affects also tolerance, because it often presets tempo and instrumentation choices, and it is clear that a loop-based tightly quantized machine groove is less tolerant than a rubato style ballad. Individual playing styles do have an impact as well."
http://www.tml.tkk.fi/Opinnot/T-111.5080/2006/Paperit/ Latency_Kleimola.pdf
---------------------------------------------
"[T]he perception of the latency between an user action and the corresponding reaction... shows a very high degree of precision: it was shown that variations in feedback delay of 20ms are, although not consciously noticed, compensated for..."
This article has some good info on jitter too.
http://gsd.ime.usp.br/~lago/masters/latency-paper.pdf
---------------------------------------------
"Since sound travels at about 1 ms per foot, latency of 7 ms is roughly equal to the maximum separation between members of a string quartet. In practice, latency of 10 ms is generally imperceptible, as long as the variation in latency (i.e. jitter) is kept small."
http://www.midi.org/about-midi/tutorial/tutor.shtml
--------------------------------------------- For realtime games (e.g. FPS, RTS), latencies greater than 50-75ms are noticeable. Upper threshold of manageable latency is 100-200ms. (paraphrase)
http://www.ibr.cs.tu-bs.de/users/wellnitz/papers/netgames2005/ netgames2005-talk.pdf?backurl=%2Fcm%2Fbib.html&lang=de
http://www.ibr.cs.tu-bs.de/users/wellnitz/papers/netgames2005/ netgames2005.pdf?backurl=%2Fcm%2Fbib.html&lang=de ---------------------------------------------
So, my whole point with all this is to say that you really don't need to worry so much about latency to have a very playable computer instrument. So if you want to make art, spend your time making art instead of getting a few less milliseconds of latency in your setup.
If you what to improve the technology, then please publish what you did (blog it, put it on a website, article, magazine, textbook...), and write code and get it out there.
.hc
------------------------------------------------------------------------
"[W]e have invented the technology to eliminate scarcity, but we are deliberately throwing it away to benefit those who profit from scarcity." -John Gilmore
hi, from my own experience (hitting keyboard keys, using microphones for voice or drumming) everything above 4 ms is irritating and therefore a pain. marius.
Hans-Christoph Steiner wrote:
So, my whole point with all this is to say that you really don't need to worry so much about latency to have a very playable computer instrument. So if you want to make art, spend your time making art instead of getting a few less milliseconds of latency in your setup.
If you what to improve the technology, then please publish what you did (blog it, put it on a website, article, magazine, textbook...), and write code and get it out there.
.hc
Honestly, I doubt you could tell the difference between 4ms and 14ms in a blind test. There have been many studies on this. If you can detect such tiny differences in onset time, you would be superhuman.
For a tonal sound like a piano, humans perceive two sounds as one if they have an onset within 30ms of each other. Humans can perceive such tiny temporal details, but this is for timbral perception rather than onset perception.
So my guess as to what is happening is that you can recognize the differences and it is something that has been deemed a source of annoyance. But when it comes down to it, all of the studies I have seen clearly show that musicians can perform equally at latencies around 50ms versus much lower latencies.
I've always wanted to make a set of patches to illustrate these concepts. I've had a couple, but they take a while to write since they have to be quite precise. There are lots of very interesting concepts of perception that are quite stunning when you try them yourself. It feels like of like you are hacking your brain, trying to figure out how it works.
.hc
On Dec 17, 2006, at 11:37 PM, marius schebella wrote:
hi, from my own experience (hitting keyboard keys, using microphones for voice or drumming) everything above 4 ms is irritating and therefore a pain. marius.
Hans-Christoph Steiner wrote:
So, my whole point with all this is to say that you really don't need to worry so much about latency to have a very playable computer instrument. So if you want to make art, spend your time making art instead of getting a few less milliseconds of latency in your setup. If you what to improve the technology, then please publish what you did (blog it, put it on a website, article, magazine, textbook...), and write code and get it out there. .hc
------------------------------------------------------------------------
If you are not part of the solution, you are part of the problem.
Hans-Christoph Steiner wrote:
Honestly, I doubt you could tell the difference between 4ms and 14ms in a blind test. There have been many studies on this. If you can detect such tiny differences in onset time, you would be superhuman.
For a tonal sound like a piano, humans perceive two sounds as one if they have an onset within 30ms of each other. Humans can perceive such tiny temporal details, but this is for timbral perception rather than onset perception.
So my guess as to what is happening is that you can recognize the differences and it is something that has been deemed a source of annoyance. But when it comes down to it, all of the studies I have seen clearly show that musicians can perform equally at latencies around 50ms versus much lower latencies.
people can perform equally, but they have to do this consciously. which is a problem, because they will fatigue more quickly.
obviously there are instruments and instruments when it comes to latency. violinist probably don't have much of a problem, but instruments with a hard attack are more likely to have. additionally, instruments where the sound is the only feedback you get, are heavily depending on low latencies. for example (i think i bring this example every time we discuss on this), we had a clarinetist here, who did not play clarinet but a wind-controller (a midi-box with a mouth-piece), controlling some hardware synthesizers. he is used to playing this instrument.
he keeps telling me (i just met him 3 days ago), that it was a pain to play with our pd-based system (which just _added_ another 15-25ms (cannot remember; it was not _very low_ though) to hist breath->midi converter latency, and hist hardware synth latency).
he gradually became louder in order to minimize the latency (with physical wind instruments this helps), and after 1 hour of playing he almost collapsed (ok, that's a bit exaggerated)
m,gsdft IOhannes
On Mon, 18 Dec 2006, IOhannes m zmoelnig wrote:
obviously there are instruments and instruments when it comes to latency. violinist probably don't have much of a problem, but instruments with a hard attack are more likely to have.
For a hard-attack sound, the spectrum of the envelope has more high-frequency content; that's one way to explain that it takes less time to measure an event.
_ _ __ ___ _____ ________ _____________ _____________________ ... | Mathieu Bouchard - tél:+1.514.383.3801 - http://artengine.ca/matju | Freelance Digital Arts Engineer, Montréal QC Canada
On Dec 18, 2006, at 4:59 AM, IOhannes m zmoelnig wrote:
Hans-Christoph Steiner wrote:
Honestly, I doubt you could tell the difference between 4ms and 14ms in a blind test. There have been many studies on this. If you can detect such tiny differences in onset time, you would be superhuman.
For a tonal sound like a piano, humans perceive two sounds as one if they have an onset within 30ms of each other. Humans can perceive such tiny temporal details, but this is for timbral perception rather than onset perception.
So my guess as to what is happening is that you can recognize the differences and it is something that has been deemed a source of annoyance. But when it comes down to it, all of the studies I have seen clearly show that musicians can perform equally at latencies around 50ms versus much lower latencies.
people can perform equally, but they have to do this consciously. which is a problem, because they will fatigue more quickly.
obviously there are instruments and instruments when it comes to latency. violinist probably don't have much of a problem, but instruments with a hard attack are more likely to have. additionally, instruments where the sound is the only feedback you get, are heavily depending on low latencies. for example (i think i bring this example every time we discuss on this), we had a clarinetist here, who did not play clarinet but a wind-controller (a midi-box with a mouth-piece), controlling some hardware synthesizers. he is used to playing this instrument.
he keeps telling me (i just met him 3 days ago), that it was a pain to play with our pd-based system (which just _added_ another 15-25ms (cannot remember; it was not _very low_ though) to hist breath->midi converter latency, and hist hardware synth latency).
he gradually became louder in order to minimize the latency (with physical wind instruments this helps), and after 1 hour of playing he almost collapsed (ok, that's a bit exaggerated)
I don't doubt that it was fatiguing to play that instrument. But do you have any specific data that shows that the latency was the source of the problem? My guess is that the reduction of feedback is essential part of this. I think that a system with so little feedback will be fatiguing to play no matter how low the latency.
Back when I was a trumpetter, when playing a MIDI trumpet, the first and dominant thing I noticed was the feeling of numbness. I was used to a lot of physical feedback in my mouth and lips, but there was much, much less with the MIDI trumpet (no vibrating lips in the mouthpiece). I don't recall noticing latency at all.
Physical feedback has a much quicker feedback loop, and perhaps more importantly, a much lower cognitive load. In order to compensate for the lack of physical feedback, you have to put a lot of effort into focusing the auditory processing parts of the brain on smaller details on a smaller timescale than usual, and that would be undoubtedly fatiguing. Normally, the clarinetist would have lots of physical feedback, so the auditory portions of the brain can be focused more on a higher timescale.
.hc
m,gsdft IOhannes
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Hans-Christoph Steiner wrote:
On Dec 18, 2006, at 4:59 AM, IOhannes m zmoelnig wrote:
he gradually became louder in order to minimize the latency (with physical wind instruments this helps), and after 1 hour of playing he almost collapsed (ok, that's a bit exaggerated)
I don't doubt that it was fatiguing to play that instrument. But do you have any specific data that shows that the latency was the source of the problem? My guess is that the reduction of feedback is essential part of this. I think that a system with so little feedback will be fatiguing to play no matter how low the latency.
he is used to play his MIDI wind-controller for years.
he kept complaining about the (increased) latency during all rehearsals.
i have no reason to believe that he lied to me, when he said he had seriously more problems on the system which added more latency.
probably he was just in the "superhuman mode", but honestly i doubt this.
64k are still enough..
mfg.asdr IOhannes
On Dec 18, 2006, at 1:16 PM, IOhannes m zmoelnig wrote:
Hans-Christoph Steiner wrote:
On Dec 18, 2006, at 4:59 AM, IOhannes m zmoelnig wrote:
he gradually became louder in order to minimize the latency (with physical wind instruments this helps), and after 1 hour of playing he almost collapsed (ok, that's a bit exaggerated)
I don't doubt that it was fatiguing to play that instrument. But do you have any specific data that shows that the latency was the source of the problem? My guess is that the reduction of feedback is essential part of this. I think that a system with so little feedback will be fatiguing to play no matter how low the latency.
he is used to play his MIDI wind-controller for years.
he kept complaining about the (increased) latency during all rehearsals.
i have no reason to believe that he lied to me, when he said he had seriously more problems on the system which added more latency.
probably he was just in the "superhuman mode", but honestly i doubt this.
64k are still enough..
Ah ok, that explains it. So he was used to the MIDI wind controller, and you presented him with a different one, with different latency. This is the case of the skilled musician sensitive to subtle differences that I mentioned in the beginning of this discussion. So I think here it is the change in latency that is the more important factor rather than purely the larger latency. I think you would also get a similar experience if you were skilled with a high latency instrument and you were presented with a low latency version of the same thing.
Believe me, I am not saying that you shouldn't be working on developing lower latency hardware and software. I think that is valuable research. What I have a problem with is the common belief that if your system has more than 10ms of latency, its unusable as a real instrument. That is just plainly untrue, and many physical, traditional instruments have much larger latencies, violin being a good example.
So if you are interested in the question of how to create low-latency systems, like many here are, please continue to work on that. But if you are interested in making music, stop worrying about latency and learn to play your instrument. Unless you have a really crappy sound card like my ooold Thinkpad. It had 850ms of latency, so yeah, that was limiting. :)
.hc
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On Mon, 18 Dec 2006, Hans-Christoph Steiner wrote:
So I think here it is the change in latency that is the more important factor rather than purely the larger latency. I think you would also get a similar experience if you were skilled with a high latency instrument and you were presented with a low latency version of the same thing.
This is because a musician automatically learns to compensate for latency by playing all notes in advance. All musicians do this, but usually having more to do with latency of the muscles and nerves. When the latency is changed, the musician has to retrain to a different compensation delay, and that's more tiresome than not having to retrain.
_ _ __ ___ _____ ________ _____________ _____________________ ... | Mathieu Bouchard - tél:+1.514.383.3801 - http://artengine.ca/matju | Freelance Digital Arts Engineer, Montréal QC Canada
Hallo, Mathieu Bouchard hat gesagt: // Mathieu Bouchard wrote:
On Mon, 18 Dec 2006, Hans-Christoph Steiner wrote:
So I think here it is the change in latency that is the more important factor rather than purely the larger latency. I think you would also get a similar experience if you were skilled with a high latency instrument and you were presented with a low latency version of the same thing.
This is because a musician automatically learns to compensate for latency by playing all notes in advance. All musicians do this, but usually having more to do with latency of the muscles and nerves. When the latency is changed, the musician has to retrain to a different compensation delay, and that's more tiresome than not having to retrain.
Being (or having been) a clarinet/sax player myself I don't believe it's the retraining that's tiresome here. It's the "not being trained correctly" that's tiring.
Compensating for latency or jitter on instruments like a piano or the drums means to hit the key or cymbal at a different time, but not to hit it harder.
On a wind instrument compensating in theory would only mean to remove the tongue from the hole or the reed at a different time to make way for the stream of air coming from your lungs, but there's more to it:
Generating sound on a wind instrument requires a certain air pressure. Now if the latency a player is used to suddenly gets bigger, it may feel as if the air pressure generated isn't high enough anymore to generate a sound immediatly. Unconsiously one may try to raise the pressure to really force a tone to come out of the instrument, when all that would really be needed is to remove the tongue at an earlier time. This also means that the playing in general becomes louder as happened in IOhannes' case and I'm sure that's what was so exhausting.
Ciao
On Dec 19, 2006, at 5:53 AM, Frank Barknecht wrote:
Hallo, Mathieu Bouchard hat gesagt: // Mathieu Bouchard wrote:
On Mon, 18 Dec 2006, Hans-Christoph Steiner wrote:
So I think here it is the change in latency that is the more important factor rather than purely the larger latency. I think you would also get a similar experience if you were skilled with a high latency instrument and you were presented with a low latency version of the same thing.
This is because a musician automatically learns to compensate for latency by playing all notes in advance. All musicians do this, but usually having more to do with latency of the muscles and nerves. When the latency is changed, the musician has to retrain to a different compensation delay, and that's more tiresome than not having to retrain.
Being (or having been) a clarinet/sax player myself I don't believe it's the retraining that's tiresome here. It's the "not being trained correctly" that's tiring.
Compensating for latency or jitter on instruments like a piano or the drums means to hit the key or cymbal at a different time, but not to hit it harder.
On a wind instrument compensating in theory would only mean to remove the tongue from the hole or the reed at a different time to make way for the stream of air coming from your lungs, but there's more to it:
Generating sound on a wind instrument requires a certain air pressure. Now if the latency a player is used to suddenly gets bigger, it may feel as if the air pressure generated isn't high enough anymore to generate a sound immediatly. Unconsiously one may try to raise the pressure to really force a tone to come out of the instrument, when all that would really be needed is to remove the tongue at an earlier time. This also means that the playing in general becomes louder as happened in IOhannes' case and I'm sure that's what was so exhausting.
Yeah, that does sounds like a very plausible explanation. It is definitely an interesting question, but unfortunately, many of these things are hard to test. Perhaps we can start some Pd patches for these tests. I think this kind of thing would really benefit from free software collaborative development.
.hc
Ciao
Frank Barknecht _ ______footils.org_ __goto10.org__
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Hallo, IOhannes m zmoelnig hat gesagt: // IOhannes m zmoelnig wrote:
he gradually became louder in order to minimize the latency (with physical wind instruments this helps), and after 1 hour of playing he almost collapsed (ok, that's a bit exaggerated)
He was probably trying to change the soft attack of his instrument into a heart attack! ;)
Ciao
he gradually became louder in order to minimize the latency (with physical wind instruments this helps), and after 1 hour of playing he almost collapsed (ok, that's a bit exaggerated)
He was probably trying to change the soft attack of his instrument into a heart attack! ;)
lol :))
On Mon, 18 Dec 2006, Hans-Christoph Steiner wrote:
Honestly, I doubt you could tell the difference between 4ms and 14ms in a blind test. There have been many studies on this. If you can detect such tiny differences in onset time, you would be superhuman.
Most people are superhuman until science tells them that they're not. That's why a lot of people hate science. ;)
For a tonal sound like a piano, humans perceive two sounds as one if they have an onset within 30ms of each other. Humans can perceive such tiny temporal details, but this is for timbral perception rather than onset perception.
Yes, it's easy to perceive changes of 1ms or even less, if one is playing twice exactly the same sounds at opposed phases, because you can listen to how exactly certain frequencies are getting cancelled and others not (and that's the same as hearing the size of the room in which the sound is, because both cases are the standing-wave phenomenon).
I'd guess that psychoacoustic experiments are right, if one considers only what is heard directly by the ear, but that's disregarding what can be heard by the mind (by indirect use of ears).
_ _ __ ___ _____ ________ _____________ _____________________ ... | Mathieu Bouchard - tél:+1.514.383.3801 - http://artengine.ca/matju | Freelance Digital Arts Engineer, Montréal QC Canada
On Dec 18, 2006, at 7:51 AM, Mathieu Bouchard wrote:
On Mon, 18 Dec 2006, Hans-Christoph Steiner wrote:
Honestly, I doubt you could tell the difference between 4ms and 14ms in a blind test. There have been many studies on this. If you can detect such tiny differences in onset time, you would be superhuman.
Most people are superhuman until science tells them that they're not. That's why a lot of people hate science. ;)
For a tonal sound like a piano, humans perceive two sounds as one if they have an onset within 30ms of each other. Humans can perceive such tiny temporal details, but this is for timbral perception rather than onset perception.
Yes, it's easy to perceive changes of 1ms or even less, if one is playing twice exactly the same sounds at opposed phases, because you can listen to how exactly certain frequencies are getting cancelled and others not (and that's the same as hearing the size of the room in which the sound is, because both cases are the standing-wave phenomenon).
I'd guess that psychoacoustic experiments are right, if one considers only what is heard directly by the ear, but that's disregarding what can be heard by the mind (by indirect use of ears).
You can't hear what your ears hear, you can only hear what your mind perceives. The auditory processing parts of the brain do massive amounts of processing of the data that comes into the ears, discarding a lot of the data, and often waiting for more data before reporting the results to the conscious part of your brain. You can directly access your ears no more readily that you can consciously control your liver or kidneys.
These phenomenon are very apparent when you try them yourself, and most of the time, even if you are fully aware of what the actual content of the sound source actually is, you cannot change your perception.
If you really want to get deep into it, I recommend Bregman's Auditory Scene Analysis. He's the main guy who has really broken down auditory perception into its constituent parts. Here are some examples from that book:
http://www.psych.mcgill.ca/labs/auditory/bregmancd.html
.hc
_ _ __ ___ _____ ________ _____________ _____________________ ... | Mathieu Bouchard - tél:+1.514.383.3801 - http://artengine.ca/matju | Freelance Digital Arts Engineer, Montréal QC Canada
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Hans-Christoph Steiner wrote:
Honestly, I doubt you could tell the difference between 4ms and 14ms in a blind test. There have been many studies on this. If you can detect such tiny differences in onset time, you would be superhuman.
please test me! are these studies made with instrumentalists and performers? (I did not read them yet, but know about perception tests in general) It is not a big deal to play scales with notes of about 40-50 ms. so 10 percent delay makes you believe you play slower. playing fast musical events makes the listener think it is one event, but actually the performer has to trigger two ore several events. it is not just pressing a key and asking did I percept the delay.. marius.
On Dec 18, 2006, at 10:52 AM, marius schebella wrote:
Hans-Christoph Steiner wrote:
Honestly, I doubt you could tell the difference between 4ms and 14ms in a blind test. There have been many studies on this. If you can detect such tiny differences in onset time, you would be superhuman.
please test me! are these studies made with instrumentalists and performers? (I did not read them yet, but know about perception tests in general) It is not a big deal to play scales with notes of about 40-50 ms. so 10 percent delay makes you believe you play slower. playing fast musical events makes the listener think it is one event, but actually the performer has to trigger two ore several events. it is not just pressing a key and asking did I percept the delay.. marius.
Yes, let's do some tests! I think they would be great patches to have. This stuff makes much more sense when you actually experience it, rather then when reading obtuse academic papers.
One key distinction here is which system you are talking about. The sense of touch/feel and muscle control are very fine grained. Good drummers can control events on scale of 5ms or less. The brain's subconscious audio processing can detect very small temporal changes and events. But when talking about the perception of audio, things are much slower. All this data is processed, packaged up, then delivered, and that takes a lot longer. So when talking about playing, listening, then adjusting what you are playing, that is a much slower loop.
That's only part of the question of handling latency. I read a study a while back that directly testing the affects of latency on highly skilled musicians. It showed that the musicians could compensate for things around 50ms, then there was a window around 300-700ms was the most difficult, then longer was a bit easier, but still hard. Perhaps there is a study somewhere that tests the latency of an instrument versus the level of virtuosity (e.g. a violin), that would cover this issue well.
I wrote up a simple test of the latency of audio and visual perception. I get pretty consistently between 200 and 250ms for sound and 300ms for visual.
One thing I wonder is what is the latency of musicians who are improvising together? I am guessing it is much closer to the 250ms reaction time than the 10ms low-latency mark. But it would be hard to measure since there is a lot of prediction happening, rather than purely listening/watching and responding.
And another references, but more related to a previous topic:
(performers are much more sensitive to jitter than latency) http://openmuse.org/transport/fidelity.html
.hc
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Mistrust authority - promote decentralization. - the hacker ethic
I just have to chime in here,
I read a book about 5 years ago that talked about a lag of consciousness as being as much as 250ms. Here is a contemporary study that shows that it takes about 100ms to even perceive something happening.
Check out Libet:
http://cornea.berkeley.edu/pubs/161.pdf
This is some *very* interesting research!
The original book talk about a special spike in the nerve signal that served as the time marker for an event. The jist is that your consciousness projects itself into the past, so that things seem to happen immediately, when they are really happening 100ms before we notice...
I believe it was a Evan Harris Walker book that referred to the work of Libet.
.b.
Hans-Christoph Steiner wrote:
Honestly, I doubt you could tell the difference between 4ms and 14ms in a blind test. There have been many studies on this. If you can detect such tiny differences in onset time, you would be superhuman.
For a tonal sound like a piano, humans perceive two sounds as one if they have an onset within 30ms of each other. Humans can perceive such tiny temporal details, but this is for timbral perception rather than onset perception.
So my guess as to what is happening is that you can recognize the differences and it is something that has been deemed a source of annoyance. But when it comes down to it, all of the studies I have seen clearly show that musicians can perform equally at latencies around 50ms versus much lower latencies.
I've always wanted to make a set of patches to illustrate these concepts. I've had a couple, but they take a while to write since they have to be quite precise. There are lots of very interesting concepts of perception that are quite stunning when you try them yourself. It feels like of like you are hacking your brain, trying to figure out how it works.
.hc
On Dec 17, 2006, at 11:37 PM, marius schebella wrote:
hi, from my own experience (hitting keyboard keys, using microphones for voice or drumming) everything above 4 ms is irritating and therefore a pain. marius.
Hans-Christoph Steiner wrote:
So, my whole point with all this is to say that you really don't need to worry so much about latency to have a very playable computer instrument. So if you want to make art, spend your time making art instead of getting a few less milliseconds of latency in your setup. If you what to improve the technology, then please publish what you did (blog it, put it on a website, article, magazine, textbook...), and write code and get it out there. .hc
If you are not part of the solution, you are part of the problem.
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On Sun, 17 Dec 2006, marius schebella wrote:
from my own experience (hitting keyboard keys, using microphones for voice or drumming) everything above 4 ms is irritating and therefore a pain.
If people had really really long arms, they could get used to playing at higher latencies; else, an arm's length is hardly ever more than 3-4 ms, using usual sound speed conversions.
_ _ __ ___ _____ ________ _____________ _____________________ ... | Mathieu Bouchard - tél:+1.514.383.3801 - http://artengine.ca/matju | Freelance Digital Arts Engineer, Montréal QC Canada
hi hans,
nice selection of papers to read before the morning coffee, however i've got some comments on them:
"As already noted in 3.1, the precedence effect says that sounds are perceived as coming from a single source when they occur within 25-35 ms time window (Haas, 1949).
right ... but in a setup with microphone->computer->speaker, there are two sources, the original source, and the processed source
"[T]he perception of the latency between an user action and the corresponding reaction... shows a very high degree of precision: it was shown that variations in feedback delay of 20ms are, although not consciously noticed, compensated for..."
This article has some good info on jitter too.
also this covers the effect of one sound source, doesn't it?
"Since sound travels at about 1 ms per foot, latency of 7 ms is roughly equal to the maximum separation between members of a string quartet. In practice, latency of 10 ms is generally imperceptible, as long as the variation in latency (i.e. jitter) is kept small."
hmm ... they are referring to one sound source ...
For realtime games (e.g. FPS, RTS), latencies greater than 50-75ms are noticeable. Upper threshold of manageable latency is 100-200ms. (paraphrase)
http://www.ibr.cs.tu-bs.de/users/wellnitz/papers/netgames2005/ netgames2005-talk.pdf?backurl=%2Fcm%2Fbib.html&lang=de
http://www.ibr.cs.tu-bs.de/users/wellnitz/papers/netgames2005/ netgames2005.pdf?backurl=%2Fcm%2Fbib.html&lang=de
... and these papers don't refer to audio at all ... more control data for video frames ... interesting to read, but they don't have anything to do with what we are talking about
So, my whole point with all this is to say that you really don't need to worry so much about latency to have a very playable computer instrument.
, if you are not going to do realtime processing of audio material
So if you want to make art, spend your time making art instead of getting a few less milliseconds of latency in your setup.
right ... it's perfectly fine to play piano pieces on a broken piano with an open window (http://www.lcdf.org/indeterminacy/s.cgi?4)
cheers ... tim
-- tim@klingt.org ICQ: 96771783 http://www.mokabar.tk
You can play a shoestring if you're sincere John Coltrane
On Sun, 17 Dec 2006, Hans-Christoph Steiner wrote:
They also concluded that latency tolerance is dependant on tempo (slower tempo equals higher tolerance), and on instrumentation. For example, if a synthesizer pad type sound is used in ensemble performance, the
That could be the (Heisenberg-like) uncertainty principle at work: slow tempos are a kind of very low frequency: 60 bpm = 1 Hz; the lower the frequency, the more time it takes to figure out that an event occurred.
However, that principle only works if it only involves sounds of that frequency. Even though the tempo can be thought of as a frequency, it would mean that a repeated measure can be thought of as a periodic sound that has certain harmonics, and those harmonics have very high indices, unlike the harmonics that dominate the timbre of single notes.
Any kind of harmonics allow us to guess a lower-frequency phenomenon (or have the impression that there is one...) before it can be perceived directly (or even without it being ever perceived directly...).
(I'm mostly saying that from a math/physics background, without much care for the actual psycho-acoustics)
_ _ __ ___ _____ ________ _____________ _____________________ ... | Mathieu Bouchard - tél:+1.514.383.3801 - http://artengine.ca/matju | Freelance Digital Arts Engineer, Montréal QC Canada
On Sat, 16 Dec 2006, Hans-Christoph Steiner wrote:
Yes, its true, I am too lazy to do an actual measurement.
Just plug a loopback wire into your speaker and mic plug. Make sure that both plugs have nonzero volume settings that are not too high. Then run doc/7.stuff/tools/latency.pd ... it does a latency detection by measuring the time to echo a click. If the volume settings are too high, it will cause fuzz, which will smear the click and make the measurement unreliable.
_ _ __ ___ _____ ________ _____________ _____________________ ... | Mathieu Bouchard - tél:+1.514.383.3801 - http://artengine.ca/matju | Freelance Digital Arts Engineer, Montréal QC Canada
hi.
Hans-Christoph Steiner wrote:
as always when it comes to latency and people tell numbers, i have to ask my question: have you measured this? how? or was it just "putting a number somewhere and assuming that it's the real latency"? how much load do your settings allow?
Yes, its true, I am too lazy to do an actual measurement. I am just talking about the buffer setting.
thank you for this clarification. i think it is important to have such things articulated correctly. as soon as the word "latency" can be found on the web, i am pretty sure that a lot of myth and rumour are involved. people keep telling that they can go as low as 3ms in pd, which is simply not possible.
For what I do, I don't really need much lower.
this is fine for you.
And always, when talking about latency, I feel the need to point out the speed of sound: 340 m/s or .34 m/ms. So if your speakers are 2m away from you, that's 6ms of latency. You could spend days tweaking your machine to get 3ms less latency, or you could move 1m closer to your speakers. Puts things into perspective...
this is correct. but unfortunately perspectives can change. as a musician you might be happy with one machine adding latency of 3ms. however, it is common practice to stack several machines (synthesizers, effect-hardware, PCs), all adding a small latency. if you have 3 machines, all with a perfectly low latency of 10ms, you get a resulting latency of 30ms which might be intolerably low.
that is just music. as soon as you get into technical applications, things get far worse (e.g. there might really be a need to get as low as 2ms).
so again: it is my concern to get clarity when people use the term "latency". i have done a lot of latency measurements over the last years; usually the numbers i saw in various control panels (be it jack, pd, rme hammerfall's settings,...) are not identical with the actual latency; though the often (not always) directly related.
mf.asdr IOhannes
PS: thanks to all of you for your explanations about latency; my remark was really not about latency (what it is; what you need) but about what we think when we hear the buzzword "latency".
On Dec 16, 2006, at 6:18 PM, IOhannes m zmoelnig wrote:
hi.
Hans-Christoph Steiner wrote:
as always when it comes to latency and people tell numbers, i have to ask my question: have you measured this? how? or was it just "putting a number somewhere and assuming that it's the real latency"? how much load do your settings allow?
Yes, its true, I am too lazy to do an actual measurement. I am just talking about the buffer setting.
thank you for this clarification. i think it is important to have such things articulated correctly. as soon as the word "latency" can be found on the web, i am pretty sure that a lot of myth and rumour are involved. people keep telling that they can go as low as 3ms in pd, which is simply not possible.
For what I do, I don't really need much lower.
this is fine for you.
And always, when talking about latency, I feel the need to point out the speed of sound: 340 m/s or .34 m/ms. So if your speakers are 2m away from you, that's 6ms of latency. You could spend days tweaking your machine to get 3ms less latency, or you could move 1m closer to your speakers. Puts things into perspective...
this is correct. but unfortunately perspectives can change. as a musician you might be happy with one machine adding latency of 3ms. however, it is common practice to stack several machines (synthesizers, effect-hardware, PCs), all adding a small latency. if you have 3 machines, all with a perfectly low latency of 10ms, you get a resulting latency of 30ms which might be intolerably low.
that is just music. as soon as you get into technical applications, things get far worse (e.g. there might really be a need to get as low as 2ms).
Just out of curiosity, what kind of applications need this?
so again: it is my concern to get clarity when people use the term "latency". i have done a lot of latency measurements over the last years; usually the numbers i saw in various control panels (be it jack, pd, rme hammerfall's settings,...) are not identical with the actual latency; though the often (not always) directly related.
mf.asdr IOhannes
PS: thanks to all of you for your explanations about latency; my remark was really not about latency (what it is; what you need) but about what we think when we hear the buzzword "latency".
Yeah, that is also a necessary clarification. "latency" is a simple number that people can use to sell things. I think that's why it is such a buzzword.
.hc
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Computer science is no more related to the computer than astronomy is related to the telescope. -Edsger Dykstra
Hans-Christoph Steiner wrote:
that is just music. as soon as you get into technical applications, things get far worse (e.g. there might really be a need to get as low as 2ms).
Just out of curiosity, what kind of applications need this?
active noise cancellation? or more general: adaptive filter systems.
mfa.dsr IOhannes
IOhannes m zmoelnig said :
as always when it comes to latency and people tell numbers, i have to ask my question: have you measured this? how? or was it just "putting a number somewhere and assuming that it's the real latency"? how much load do your settings allow?
:) yes, and this latency question is quite a cyclic thread on this list. It comes back regularly (pd-list archive is your friend).
Myself, I've been pretty much into fine tuning of my system in the past to reach the lowest latency possible, without really understanding basic concept such as the latency of the hardware, of the kernel, of the software itself etc etc....
My main concern today is much simpler, if I can't "feel" any latency with my hdsp when using Pd and if I don't have any xruns then I'm happy.
On the kernel side, in pure:dyne we've been playing with RT Ingo Molnar's patches and this results in a very nice system for audio (without xruns on jack on regular hardware and oldy pIII ...)
a.
-- 320x200.goto10.org
I have measured such things precisely when the application required it. Its also fairly trivial to "hear" the latency by clapping into a microphone and monitoring it over headphones after it passes through the system. A 10msec difference is quite audible.
A general method for latency measurement of any system is described in this paper:
Matthew Wright, Ryan Cassidy, Michael Zbyszynski, Audio and Gesture Latency Measurements on Linux and OSX, Proceedings of ICMC 2004, Miami
On Dec 16, 2006, at 5:38 AM, IOhannes m zmoelnig wrote:
Hans-Christoph Steiner wrote:
Apple puts good audio hardware in their laptops. I can get 14ms of latency on Mac OS X with Pd without really trying (I just set it to 14ms). I can get down to 11ms if I don't mind clicks when I operate the menus and switch to other applications.
as always when it comes to latency and people tell numbers, i have to ask my question: have you measured this? how? or was it just "putting a number somewhere and assuming that it's the real latency"? how much load do your settings allow?
mg-asdr IOhannes
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hi IOhannes,
for me low latency means that i can manipulate (effecting, recording, fiddling, destroying) in realtime 8 adc~ without adding a lag (and hopefully someday without glitches). musicians cannot process very well delay in what they are playing, it's worst for drummers i guess!
patrick
Yeah, drummers have by far the most sensitivity to latency. That's something I overlooked with my last post about latency. Good drummers can also control impacts to sub-millisecond accuracy, in the case of something like two drumsticks hitting one after the other. This is due to muscle control though, this is happening far to quickly for the audio feedback loop.
But the crux of the matter is that looking only at latency is missing whole picture of what is going on. You would be much better off with a solid 30ms of latency than a range of 5-10ms of latency. So jitter measurements should be performed as well.
Another thing that is not mentioned is blind testing. If you believe that something should be better, you will perceive a difference regardless of whether its there or not. A good example is your mouse. Try moving the mouse around and then guess the latency of your mouse. For a USB mouse, the best it gets is 10ms (with low jitter), yet I doubt few notice it.
That points out another key aspect of this: what you are used to. Musicians are quite sensitive to change. Violinists can tell amazingly tiny differences in the response of different violins, for example. You will notice a change, but if you practice with any given setup, you will adapt. I doubt that there is a noticeable difference in performance abilities for people of equal experience on a system of 10ms vs. a system of 30ms.
.hc
On Dec 16, 2006, at 5:03 PM, patrick wrote:
hi IOhannes,
for me low latency means that i can manipulate (effecting, recording, fiddling, destroying) in realtime 8 adc~ without adding a lag (and hopefully someday without glitches). musicians cannot process very well delay in what they are playing, it's worst for drummers i guess!
patrick
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Hallo, Bryan Jurish hat gesagt: // Bryan Jurish wrote:
(B) is the onboard soundcard on said laptop tolerable (A/D-D/A sync, general quality, etc.)? [i realize it probably won't be great; i just can't afford a hammerfall, my quattro is basically crap, and the adc on my terratec usb is thoroughly unsatisfying]
Being in part responsible for your choice of USB card: I also upgraded from the cheap Terratec USB to the Terratec Phase26, which has really good ADC.
Note that on Linux all USB soundcards have the same latency
Another card family to look at my be the Echo Indigo cards (PC-Card). They lack in channels, but otherwise are very good from what I heard.
Firewire seems to be an option nowadays too on Linux thanks to Freebob, but I don't have any experiences with it.
USB and Firewire may have the advantage, that they are somewhere else if a laptop is stolen. ;) (Sorry, I just couldn't resist to make this silly joke.)
The newer Intel soundcards (HD Audio) on paper should have very good specs, but I have no knowledge how good this translates to the real world.
Ciao
moin Frank, moin again list,
On 2006-12-15 23:28:49, Frank Barknecht fbar@footils.org appears to have written:
Bryan Jurish hat gesagt: // Bryan Jurish wrote:
(B) is the onboard soundcard on said laptop tolerable (A/D-D/A sync, general quality, etc.)? [i realize it probably won't be great; i just can't afford a hammerfall, my quattro is basically crap, and the adc on my terratec usb is thoroughly unsatisfying]
Being in part responsible for your choice of USB card: I also upgraded from the cheap Terratec USB to the Terratec Phase26, which has really good ADC.
no blame attaches. any similarity between the soundcards i have purchased and those which any person or persons real and/or fictional may or may not have reported using, tested and/or reviewed for major national computing-technology periodicals is unintended and purely coincidental.
really. ;-)
USB and Firewire may have the advantage, that they are somewhere else if a laptop is stolen. ;) (Sorry, I just couldn't resist to make this silly joke.)
ok, i guess i deserved that one :-P
marmosets, Bryan