tri~ issues

    Feb 08 2006 | 3:06 am
    I have built a synth that includes the tri~ object. I have noticed some strange behavior which illustrated by the patch below. In my synth I am using a line~ object before an mtof~ object. I use the line~ object to slide between pitches sent to the various oscillators including tri~. When the slide time is 0 the signal from tri~ seems to phase in and out. It is most noticeable when the signal passes through an overdrive~ object which is also part of my synth. Anyone know why this is happening and how I can avoid it?

    • Feb 08 2006 | 8:08 am
      Hi Simone,
      I want to thank you very very much. I have had several reports of problems with tri~, and I was able to reproduce them, but I was never able to figure out just what the heck was wrong with the object. I wasted many hours exploring all sorts of complicated solutions for what I thought was the problem, but I was never able to fix it. But for some reason tonight, after looking at your VERY CLEAR EXAMPLE PATCH, I opened up the code and the bug was fixed in less than a minute. Wow that feels good!
      A fixed version of tri~ will be in the next Max/MSP update. I am currently away from my office and don't have an OS X computer handy, but I'll be home tomorrow and will make the fixed externals available tomorrow night.
    • Feb 10 2006 | 1:40 am
      just wondering when the fixed version of tri~ might be available...
      glad it was a simple fix...
    • Feb 10 2006 | 8:28 am
      Another problem with tri~ is that when you play a bit with the duty cycle parameter (expecially if you go a few times from 0 to 1) the signal become eventually a stream of "inf"s.
      -- HomePage: Computer Music Italian Forum
    • Feb 14 2006 | 1:24 am
      > just wondering when the fixed version of tri~ might be > available...
      It's available now from the incremental downloads page:
    • Feb 14 2006 | 1:25 am
      Hi Maurizio,
      Sorry, but I'm not able to reproduce your bug with the latest version of tri~.
    • Feb 17 2006 | 2:52 pm
    • Feb 17 2006 | 3:46 pm
      Dear Ben,
      unfortunately I still can reproduce it, expecially when I change the duty cycle very fast a few times...
      Ibook g4 1.2 Mhz OSX 10.3.9 MaxMSP 4.5.6
      NB I only have one version of tri~ in my computer. The creation date is Feb 14 2006
      -- HomePage: Computer Music Italian Forum
    • Feb 17 2006 | 5:52 pm
      I can reproduce this bug on my machine:
      OSX 10.3.9 MaxMSP 4.5.6 Newst version of tri~ powerbook g4 1.5 Ghz
      I did some digging, however, and I'm finding that the infs don't seem to be related to just changing the duty cycle, but rather, subjecting the duty cycle parameter to "unnecessary" roughness. I can use a dc-offset [cycle~ 10.] to modulate the duty cycle all day long, and there's no issue, but if I run it through [~* 100] -> [clip 0. 1.]... the min/max values of the resulting waveform from tri~ are... strange. FWIW.
    • Feb 28 2006 | 6:22 pm
      Dear tri~ lovers,
      I believe we are moving closer to a well-behaved object. Please download and install the new version at the incremental updates page at
      Do not hesitate to let me know about any bugginess that persists!
      Dutifully yours, Ben "tri~ceratops rex" Nevile