popping sounds in MSP
Hey all,
Simple dilemma (I hope!)
But when I'm controlling values within an audio environment, for example, EQ parameters set up in MSP, I here popping sounds every time I increase or decrease the values to a parameter.
I remember reading a way of counteracting this problem before, but can't seem to find it.
Any ideas?
Hi
there could be a hundred different reasons for this, dependent on your patch, your OS, your DSP settings and/or your soundcard/hardware setup. Post a patch and ensure that your buffer and in/out signal vector sizes are optimized (often 512/64 respectively). But without seeing your patch it's impossible to be more specific......
Brendan
usually that happens when you don't use the pack/line combo - especially when using floats to control an audio amp or filter. But like n00b said without the patch it's guess work.
so buffer and vector sizes are as stated, and I'm thinking it has to do with what grizzle said.
I've posted part of the patch, where I'm using three values of x,y,z, data from a chronos watch to control an EQ, and then on the right hand side you can see that I'm tapping into this feed to use the acceleration data to control a pitch elsewhere.
The data from the chronos though is lots of information, very fast, which I'm thinking is what is causing the pops? The numbers change very rapidly.
So pack/line combo will need to be used to slow down the data flow a bit then?
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I had a look at your patch and when I use it I don't get any pops but I am just manually moving the slider - I added in a pack/line it might help but I didn't hear pops in the first place and the controlled parameter is not audiorate, where the pack line~ combo is most important, so...??? - I would look at [speedlim] and [change] and there is a sensor tamer patch in the extras/examplesoverview - Like I said I can't hear the pops so I am not sure.
Ok, so the plot thickens.
I tried your patch grizzle, and it still has distinct pops. I tried different sound cards thinking I may be getting some sort of feedback, but that's not the case either.
I've tried different samples, thinking I may have had too much gain to begin with. This was true, but then I can also get it to pop/crackle with different recordings also.
To be honest, it behaves like the crackles are in time with the number in the number box, moving from the slider.
Its really concerning me, as I have a few gigs coming up!
In my audio status it reads:
I/O vector size: 512
Signal Vector size 64
Sampling rate 44100
Scheduler in overdrive - unchecked
in audio interrupt - unchecked
CPU limit - 0%
Vector optimization - checked
Parallel processing - checked
Not sure if thats any help, but I am getting a little desperate for help! Any ideas of what else may cause pops/crackles/noise? (unfortunately, not intentional noise...).
Hi
in a recent patch of mine I was also getting what I can call 'zipper' noise. In a Karplus string model, I was varying the delay time with an integer box. Without knowing the true technical details behind this, it appears that the numbers were changing faster than the Max control rate (is it 1 command per 20ms?) - probably wildly innacurate. I solved it simply by placing a [sig] between the number and its destination, converting the control rate signal into an audio one. A simple lowpass filter, [onepole~ 0.1] for example, can also slow down and smooth the data flow
Brendan
HTH
Yeah, this problem is still happening...
Thanks for the advice n00b_meister, and it does make sense. I also thought that perhaps there were jumps in data, so that if, for example, my slider moved faster than the numbers could count, it would miss data. And poppity pop pop.
But I tried another 'hit every number trick' and I'm still getting the pops. Its really weird. I'm wondering if its a problem with my computer to be honest. I'm finding it very odd that it works fine on others computers and not mine.
Could this be a max 6 VS snow leopard problem?
I'm also having issues it seems with max 6 crashing alot, more precisely freezing the GUI. When I'm playing audio, the audio will keep going, but the visual interface freezes, and sliders don't graphically respond even though they audibly respond.
Getting this close to a major performance, am I being a drama queen if I run to upgrade my computer? Or is there a chance this is a hardware related issue in my computer?
I listened again just to make sure and I did hear some junk on the last of the sliders - i put in a pack/line and it was better but the noise only happens if you moves the controls really fast. If you plan to do really fast parameter changes then you should work at audio rate and not control rate - so maybe look at using reson~ or fffb~ or svf~ or some kind of fft solution. For me it is fine as long as I don't continuously ramp up to the max and down to the min. If I use it in a normal kind of way it is fine.... like it is an EQ patch not a filter patch - EQ is not supposed to be modulated extremely quickly continuously - so thats why I say maybe try a filter instead.... even have a look at the forbidden planet patch in the examples....
hope you get it sorted...
Thanks grizzle, your input has been most valuable! Many many thanks.
The world of fft is definitely something I'll look into.
I have the problem sorted now it seems. I was having another issue with max 6 which I thought was unrelated, but perhaps it was.
My GUI was freezing quite regularly, so I contacted cycling74 who recommended the latest update... seems kind of obvious now but I didn't actually think to look if there was one newer than what I had...
But it seems to have dramatically fixed the popping also.
Big sigh of relief. Thanks again everyone for all your help! :)