June 2011 - chuck-users - lists.cs.princeton.edu

Instrument Pickups for Ajay and Others
by Les Hall 04 Jun '11

04 Jun '11

This post is somewhat off-topic to ChucK itself, so please skip it if that bothers you, thanks. All this celebration of Ajay Kapur and the amazing work that he and his students are doing reminded me of a sort of reinvention that my Swedish friend Are and I created together some time ago. It's a type of stringed instrument pickup that has unique properties making it very suitable for creating one's own stringed instruments. I know that part of the ChucK world involves creating unique instruments including stringed ones, so I thought I'd post here. I say reinvented because after we created it, we found prior art in the patent record going back to the 1930's if I recall correctly, and we never did patent out little twist on the theme that made it practical today, so it's yours to use freely. It works by putting neodymium magnets under the strings and then amplifying the tiny currents created in the strings themselves as they vibrate in the magnetic field. Since there are no coils of wire, there is no second-order filter to distort all those beautiful harmonics, and the sound is more "clean" or harp-like than a conventional wound pickup. There are quirks to these pickups, but they are minor to most listeners. You can read all about this new-old pickup system here: http://echuck.othomann.de/eChucK/Guitar_Kit.html Oh, and we did ask for a small contribution from anyone who used it, but not only is that a voluntary gesture, for educational purposes we can waive it altogether. If someone uses the pickup system and tells us about it, that will be plenty reward enough. Please feel free to forward this message or the web link to any related list or person or whatever. Thanks, Les

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Re: [chuck-users] An Eastern-flavored Happy Birthday to Ajay Kapur
by Perry R Cook 04 Jun '11

04 Jun '11

AP, BBC, and many others came to cover the spring show (in which I briefly guest-appeared). Lots of coverage: AP Video: http://video.aol.com/video/calif-students-build-musical-robots-then-jam/962… The Boston Globe http://www.boston.com/news/education/k_12/articles/2011/05/13/robots_get_th… Washington Post http://www.washingtonpost.com/entertainment/robots-get-their-groove-on-make… Sydney Morning Herald http://news.smh.com.au/breaking-news-technology/robots-get-their-groove-on-… San Francisco Chronicle http://www.sfgate.com/cgi-bin/article.cgi?f=/n/a/2011/05/13/state/n025049D6…

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An Eastern-flavored Happy Birthday to Ajay Kapur in ChucK
by Perry Cook 04 Jun '11

04 Jun '11

Hi all, Ajay is one of the only of us who actively uses ChucK everyday to drive robots!! It's amazingly fun to hook up to his critters via OSC and get them banging away. For that, and many of the other awesome things he does and does for us, I offer this: http://www.cs.princeton.edu/~prc/HBDAjay2011 The code is butt-ugy, inline, copy-paste. That's how I compose short one-off ChucK things. No comments, just music :-) Enjoy!!! PRC

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exponential envelope
by Alex French 03 Jun '11

03 Jun '11

Is there a generally-accepted method for creating exponential envelopes? It can be managed with Gen5, but the result is somewhat clumsy and requires a very fast loop. -Alex

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More Holodeck Phaser Practice!
by Les Hall 03 Jun '11

03 Jun '11

Greetings Earthlings, Quark Industries is happy to present to you version 3 of our holodeck phaser target practice program, located at the following link: http://electro-music.com/forum/viewtopic.php?p=332018#332018 Quark's CEO and chief bottle washer was quoted as saying: "With the popularity of shooter1.ck reaching an unprecedented 10 starships, we felt it was time for an update. So here is shooter3.ck with several playability improvements - enjoy!" Note: my high score is 6, what is yours? Les

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Information request
by luca paganotti 01 Jun '11

01 Jun '11

Hi all, I'm trying to use/evaluate the usage of faust, pd and ChucK for a single application that is not directly related to music. I work as a developer for noise related applications (in particular we manage aircraft noise and in general noise pollution). I briefly explain what I would like to do. Let's say that I have a noise source that I would like to limit. Let's say that I measure the noise with a microphone in the vicinity of the noise source where i think the noise could disturb someone. The mic input is needed to compute some meaningfull indexes in a defined time interval, let's say 1 second or more, and then this value could be used as a reference to change the amplitude of the noise source if it exceeds the reference value. I make a couple of examples: 1. maybe I need to limit the noise production of a pub where there is live music so to reduce noise pollution outside the pub ... 2. maybe I gather with my friends to play some music in my house and I would like not to annoy my neighbours ... I've read the ChucK docs and found that I can have analyzer units but at the moment they are only built in (fft, ifft, ...) and that in the near future there will be the possibility to develop my own analyzer unit ... So my questions are: 1. Do you think that ChucK could be a profitable choice to have this job done? 2. Have you plans and timings for the user built analyzers unit support in ChucK? Thanks by now for any answer. Luca Paganotti

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chuck linux-alsa in Ubuntu 11.04
by Alex French 31 May '11

31 May '11

Hi all, I've become quite interested in procedural/fully synthesized audio for game development, and I've tried out a lot of different tools, including cmus, supercollider, puredata, and chuck. I really like chuck, because it seems fairly lightweight and simple compared to the others. The only problem is that I can't get it to work in Ubuntu using alsa. It works with jack, which is fine for me, but I don't want my users to have to install and deal with jack just to play my game. So here's my situation... I'm running 32 bit Ubuntu 11.04. I have onboard sound on my motherboard, through the nVidia MCP55 chipset: 00:0f.1 Audio device: nVidia Corporation MCP55 High Definition Audio (rev a2) Unfortunately, that device crapped out on me a year or so ago, so I replaced it with this: 02:09.0 Multimedia audio controller: C-Media Electronics Inc CM8738 (rev 10) ...which is a Diamond XS51 PCI audio card. I also have this, courtesy of my video card: 01:00.1 Audio device: ATI Technologies Inc Barts HDMI Audio [Radeon HD 6800 Series] That makes for a fairly complex setup. Here's what chuck sees: $ ./chuck --probe [chuck]: found 7 device(s) ... [chuck]: ------( chuck -- dac1 )--------------- [chuck]: device name = "hw:NVidia,0" [chuck]: probe [success] ... [chuck]: # output channels = 8 [chuck]: # input channels = 2 [chuck]: # duplex Channels = 2 [chuck]: default device = YES [chuck]: natively supported data formats: [chuck]: 16-bit int [chuck]: 32-bit int [chuck]: supported sample rates: [chuck]: 44100 Hz [chuck]: 48000 Hz [chuck]: 96000 Hz [chuck]: 192000 Hz [chuck]: [chuck]: ------( chuck -- dac2 )--------------- [chuck]: device name = "hw:NVidia,1" [chuck]: probe [success] ... [chuck]: # output channels = 2 [chuck]: # input channels = 2 [chuck]: # duplex Channels = 2 [chuck]: default device = NO [chuck]: natively supported data formats: [chuck]: 16-bit int [chuck]: 32-bit int [chuck]: supported sample rates: [chuck]: 44100 Hz [chuck]: 48000 Hz [chuck]: 88200 Hz [chuck]: 96000 Hz [chuck]: 192000 Hz [chuck]: [chuck]: ------( chuck -- dac3 )--------------- [chuck]: device name = "hw:NVidia,2" [chuck]: probe [success] ... [chuck]: # output channels = 0 [chuck]: # input channels = 2 [chuck]: # duplex Channels = 0 [chuck]: default device = NO [chuck]: natively supported data formats: [chuck]: 16-bit int [chuck]: 32-bit int [chuck]: supported sample rates: [chuck]: 44100 Hz [chuck]: 48000 Hz [chuck]: 96000 Hz [chuck]: 192000 Hz [chuck]: [chuck]: ------( chuck -- dac4 )--------------- [chuck]: device name = "hw:CMI8738,0" [chuck]: probe [success] ... [chuck]: # output channels = 2 [chuck]: # input channels = 2 [chuck]: # duplex Channels = 2 [chuck]: default device = NO [chuck]: natively supported data formats: [chuck]: 16-bit int [chuck]: supported sample rates: [chuck]: 5512 Hz [chuck]: 8000 Hz [chuck]: 11025 Hz [chuck]: 16000 Hz [chuck]: 22050 Hz [chuck]: 32000 Hz [chuck]: 44100 Hz [chuck]: 48000 Hz [chuck]: 88200 Hz [chuck]: 96000 Hz [chuck]: [chuck]: ------( chuck -- dac5 )--------------- [chuck]: device name = "hw:CMI8738,1" [chuck]: probe [success] ... [chuck]: # output channels = 6 [chuck]: # input channels = 0 [chuck]: # duplex Channels = 0 [chuck]: default device = NO [chuck]: natively supported data formats: [chuck]: 16-bit int [chuck]: supported sample rates: [chuck]: 5512 Hz [chuck]: 8000 Hz [chuck]: 11025 Hz [chuck]: 16000 Hz [chuck]: 22050 Hz [chuck]: 32000 Hz [chuck]: 44100 Hz [chuck]: 48000 Hz [chuck]: 88200 Hz [chuck]: 96000 Hz [chuck]: [chuck]: ------( chuck -- dac6 )--------------- [chuck]: device name = "hw:CMI8738,2" [chuck]: probe [success] ... [chuck]: # output channels = 2 [chuck]: # input channels = 2 [chuck]: # duplex Channels = 2 [chuck]: default device = NO [chuck]: natively supported data formats: [chuck]: 16-bit int [chuck]: 32-bit int [chuck]: supported sample rates: [chuck]: 44100 Hz [chuck]: 48000 Hz [chuck]: 88200 Hz [chuck]: 96000 Hz [chuck]: [chuck]: ------( chuck -- dac7 )--------------- [chuck]: device name = "hw:Generic,3" [chuck]: probe [success] ... [chuck]: # output channels = 2 [chuck]: # input channels = 0 [chuck]: # duplex Channels = 0 [chuck]: default device = NO [chuck]: natively supported data formats: [chuck]: 16-bit int [chuck]: supported sample rates: [chuck]: 32000 Hz [chuck]: 44100 Hz [chuck]: 48000 Hz [chuck]: [chuck]: ------( chuck -- 2 MIDI inputs )------ [chuck]: [0] : "Midi Through Port-0" [chuck]: [1] : "C-Media CMI8738 MIDI" [chuck]: [chuck]: ------( chuck -- 4 MIDI outputs )----- [chuck]: [0] : "Midi Through Port-0" [chuck]: [1] : "C-Media CMI8738 MIDI" [chuck]: [2] : "OPL3 FM Port" [chuck]: [3] : "qjackctl" [chuck]: I've tried using dacs 4-6 with pasuspender to suppress pulseaudio, but nothing seems to work. The same thing happens without pasuspender; I don't know if it's actually required, but it's something I tried. Anyway, in an attempt to get some more information, I increased the log verbosity: $ pasuspender -- ./chuck --verbose5 --dac5 moe.ck **snip** [chuck]:(2:SYSTEM): | sample rate: 48000 [chuck]:(2:SYSTEM): | buffer size: 512 [chuck]:(2:SYSTEM): | num buffers: 8 [chuck]:(2:SYSTEM): | devices adc: 0 dac: 5 (default 0) [chuck]:(2:SYSTEM): | adaptive block processing: 0 [chuck]:(2:SYSTEM): | channels in: 2 out: 2 **snip** [chuck]:(3:SEVERE): starting real-time audio... [chuck]:(2:SYSTEM): RtApiAlsa: callback thread error... [chuck]:(5:INFORM): | (RtApiAlsa: audio read error for device (hw:NVidia,0): Input/output error.) [chuck]:(5:INFORM): | closing thread... What's going on here? I asked for the CMI8738, but I'm getting I/O errors from the nvidia device. At this point I'm completely lost. Help? -Alex

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