- From: Jussi Kalliokoski <jussi.kalliokoski@gmail.com>
- Date: Thu, 2 Aug 2012 23:42:49 +0300
- To: Peter van der Noord <peterdunord@gmail.com>
- Cc: public-audio@w3.org
- Message-ID: <CAJhzemV9w7R5BJ1+We-pxn8_BgDCw4P5ZyP-3h0CYe-kiSOMvQ@mail.gmail.com>
Hey Peter! I think this is because the JSNode has a delay equivalent to the buffer size, hence if you have parallel graphs that contain a different number of JSNodes, they will arrive to the common destination at a different delay. Cheers, Jussi On Thu, Aug 2, 2012 at 11:35 PM, Peter van der Noord <peterdunord@gmail.com>wrote: > I'm having a strange problem with some signals at the moment and i've been > staring at it for way too long now, so i thought: why not put it up here, > maybe someone sees what's going on. It's a lenghty story, so if you want to > hang on...i'll try to explain :) > > As you may know, i'm writing a modular synthesizer: > > http://petervandernoord.nl/patchwork_js (maybe clear your cache if you've > been there before) > > If you click the 'json to patch' button, a testpatch will be set. > (Important to know: all custom nodes will be created with the buffer-size > that's selected in the pulldown on the right). The patch contains 3 modules > (in patchwork, a module can contain one or more audionodes, with the > module's in/outputs mapped to certain in/outputs of the containing nodes): > > - The destination, which contains a normal destinationNode > http://localhost/patchworkjs/js/modules/DestinationModule.js > > - a clockmodule. one custom js node > http://localhost/patchworkjs/js/modules/DestinationModule.js > > - a triggersequencer, also one custom node. > http://localhost/patchworkjs/js/modules/TriggerSequencerModule.js (the > audioprocess callback is at the bottom) > > What is happening in the patch: the clock sends out single values of 1s > (all other values are 0) on a given interval (set in BPM). The sequencer > checks on every incoming value if that value is >0 AND the previous one was > <=0 (i'll call that a clock-pulse). If that is the case, its > SequencerParameter will proceed to the next step. A sequencer-parameter > (actually it is a LogicSequencerParameter, but that's almost the same - it > has one extra method) can be found here: > > http://localhost/patchworkjs/js/params/SequenceParameter.js > > It's basically just an array filled ith 0s and 1s (you can set a 1 by > clicking somewhere on the sequencer), and increases the current position > when it gets a next() command. So, back to the the sequencer module: If it > received a clock-pulse, it proceeds the sequencer. Then, if the (new) value > of the sequencer-parameter is 1, the sequencer will write a 1 in its > outputbuffer as well. > > My issues: > - in the testpatch, both the clockmodule and the seq-module are connected > to the output. if you activate some steps in the sequencer, you will hear > that the clicks do not run in sync. I have no idea why that is, the > stepsequencer writes a 1 in exact the same iteration as it reads the > incoming 1s from the clock. In my opinion, they should run exactly in sync. > - When you change the buffersize (which is for the customnodes) you will > hear that the timedifference between the ticks changes (since there's no > clear, you have to refresh the page, set another buffersize and click 'json > to patch') > - Something else i noticed: when i run just a clock module connected to > the output, with a very low buffersize (256, 512), the clock seems to run > very, very irregular. > > > So, my main question: Does anyone have any idea why those two modules do > not run in sync when both connected to the output? > > > Peter > >
Received on Thursday, 2 August 2012 20:43:17 UTC