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

Re: [chuck-users] Electronic ChucK
by inventor-66＠comcast.net 04 Oct '08

04 Oct '08

Mike, I'm open to any digital control interface that anyone wants to use. Although I do have to define *some* standards, I'm trying to be as open and flexible as possible. If you've got an Arduino and you want to connect it to EChucK, then I say go for it. Just make sure you know what you are doing and don't fry another module, haha. Now having said that, I'm planning to actually *sell* PIC processor boards. The dsPIC I have chosen is $3 US in low quantities direct from Microchip, and for that you get a stand-alone 40 MIPs DSP with 6 channels of oversampled audio in and a few PWM outputs. That's a lot of processor for three bucks and it is only 18 pins so it is small too. The dsPIC is my next circuit board, and it will be programmable to be a do-it-all module. Whatever you need, a SinOsc, an FFT/IFFT class, a delay line, a multiplier - if you can program it then you can load up one of those modules to do the job. So some of the more digitally inclined folks will buy a bunch of dsPIC modules and code them up. Others will prefer to buy true analog modules, both will be available. Now, since folks will be learning and using PICs, natually the PIC interface products like USB, UART, RF, etc. will become product options. But that doesn't mean you can't use an Arduino if you want to do so. Of course smart technical people, being resourceful and creative, will do whatever they want regardless of the standards I set anyway, lol. So all I can really do is set standards for *my* boards and ask that people generally try to stick to them unless there is reason to do otherwise. I hope that clears things up a bit. Take care, Les (Inventor)

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Time to SMIRK!
by Rebecca Fiebrink 04 Oct '08

04 Oct '08

Hi folks, We call your attention to the Small Music Information Retrieval toolKit, SMIRK, available and waiting for your download and abuse at http://smirk.cs.princeton.edu . Like smelt (http://smelt.cs.princeton.edu), SmirK is a set of ready-to- use building blocks and examples. It's all written in ChucK, so there's nothing to "install." (But it does come with its own ChucK class hierarchy, which you'll have to download, so you'll have to set your path carefully, unlike smelt. See the comments in each file for instructions.) Use the code as-is, or modify it to suit your needs. sMiRk includes 2 key components: feature extraction (using the UAna framework at http://chuck.cs.princeton.edu/uana/) and classification (e.g., k-nearest-neighbor, AdaBoost). This comes with some simple keyboard-based and MAUI-based interfaces for training and running classifiers. For example: * Train a classifier to recognize vowels versus consonants, and then apply it to pan the incoming audio appropriately * Do the same based on instrument, speaker, or even genre of songs in your iTunes collection * Recognize different trackpad or accelerometer gestures * Do all this training on-the-fly, in real-time! * Use MAUI to do simple visualizations of features and classification results (for Mac only; not required) We'd love you to download smirk, read about it, ask questions about it, abuse it, request new features, and contribute to it yourselves. We've set up a wiki at http://wiki.cs.princeton.edu/index.php/Chuck/SmirK where you can do all these things. Meanwhile, we're continuing to hack away... Cheers, Rebecca, Ge, and Perry

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Re: [chuck-users] Time to SMIRK!
by Rebecca Fiebrink 03 Oct '08

03 Oct '08

> Problem solved. Please recommence your surfing! > This sounds good but I'm getting a "403, forbidden" on that and on > /index.html there. /index.htm gives me a 404 so I suspect there is a > issue > with settings on the index file. Regarding include/import mechanism: I agree, it would be totally wonderful. My hack for getting around this in smirk: A cludgey "add-machine" file for all mini-projects/examples. I don't have anything better right now, sorry! Rebecca

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Re: [chuck-users] Electronic ChucK
by inventor-66＠comcast.net 03 Oct '08

03 Oct '08

Mike, The computer interface I am planning is an analog one. It will receive stereo audio from the headphones jack and send stereo audio to the line-in Jack. This way we can generate whatever signals we want from ChucK and pipe them into EChucK on adc.left and adc.right. We can also receive two separate audio signals on dac.left and dac.right. I was sort of generalizing the stereo input and outputs into a pair of do-anything audio outs and do-anything audio ins. This opens up many possibilities for ChucK to control EChuck or provide signals for EChucK. Don't have a filtered noise module in your EChucK module collection? Just write a ChucK program and you've got it. Want an analog multiplier but don't have a multiplier module? send the two signals to line-in, have ChucK multiply them, and receive your result on headphones out. That's the idea. The computer interface module will be just a quad opamp circuit with perhaps variable gain/attenuation and diode clamping for the line-in signals to protect your computer. It should be quite low in cost, just $5 or so in parts + profit margin for the seller. Other computer interfaces such as USB, parallel port, etc. are planned but I'm doing the simplest, easiest modules first to get a working prototype built and tested/working. Cheers! Les (Inventor)

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Re: [chuck-users] Electronic ChucK
by inventor-66＠comcast.net 03 Oct '08

03 Oct '08

I threw together a quick starter web page with a somewhat funny introduction. It has links to the Eagle CAD files so you can download them and check them out. So far there is only the Power and ADC microphone interface. Here is the link: http://www.freedomodds.com/music/echuck/index.html I think that perhaps the next most important module for me to create is a computer interface module. Please let me know what other things you would like to see on the page or created next. Also if you would like to contribute in some way, tell me that as well. Cheers! Les (Inventor)

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Re: [chuck-users] Electronic ChucK
by inventor-66＠comcast.net 03 Oct '08

03 Oct '08

Peter, Yes, any kind of transducer would be an excellent addition to EChucK. I'm open to anything that is inexpensive and adds to the fun. I'm most excited about the notion of making music synthesis in all its forms accessible to us, and especially to kids. Breadboarding is inaccessible due to cost, complexity, and learning curve. Traditional synthesizers are inaccessible due to cost and size. Typical electronic experimenter's kits have the same problem as breadboarding, though they do make it fun with sensors and output devices. What is needed is something with a granularity that exists somewhere above component level and below system level, while still retaining the component level cost advantage. And how boring and useless would EChucK be without a diverse selection of sensors? I'd like to have or facilitate the building of rain detectors, wind sensors (weather sensors), EKG sensors to detect heartbeats, and Kassens' suggestions of excited resonators is perfect for EChucK. Well, perhaps my imagination runs amok, I've had only a few short naps these past two days so I'm a bit over tired. Oh, by the way, the EChucK web site is now up to 400 hits in less than 24 hours of existence. I sure hope this means some folks will collaborate, that would be great fun! And as Ge once said... "For those about to ChucK, we salute you!" Les (Inventor)

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Re: [chuck-users] Is it possible to get mp3 output instead of wav?
by Manish Mittal 03 Oct '08

03 Oct '08

> Hi, My first post here. I stumbled on chuck this morning and have not > been able to take my hands off it.. its fun!! While going through the manual > I found chuck can write a Wav file to disk, can it also write an .mp3 file? > I searched through the chuck-users archives messages but found no direct > response. > > Also, I was curious if chuck can read in from a mp3 file. If not, are you > aware of a command line tool that can convert from mp3 to wav and then feed > into chuck (that's assuming wav files can be chucked). One of the reasons to > try something like above is to make my own karaoke files (20-30 of them), > but all my songs are mp3. I was planning to use chuck to do some frequency > filtering to achieve karaoke effect and then possibly add some computer > generated sounds to create a mix. > > Thanks for developing chuck .. pretty cool :-) > Manish >

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Re: [chuck-users] Electronic ChucK
by inventor-66＠comcast.net 03 Oct '08

03 Oct '08

Wow. I posted to the ChucK forum about EChucK and some nice person copied the post, cited the origin, and put it on an RSS Feed for synthesizers. This quick little EChucK web page that I worked on all night has now gotten close to 300 hits! That's a lot more than my usual 20 hits a day for the whole music site. There hasn't been much response other than a lot of web hits, but google and my hit counter say they are mostly from unique users, so a lot of people are taking a look at EChucK. The web being what it is, I have heard and found myself that I only get about one email per 1,000 web hits so I'm not surprised nobody has emailed yet. In other good news, the poll I put on the announcement indicates that four people are willing to help out with the project. So it's been an exciting night. Note that the EChucK web page has been expanded and now has sub-pages with JPGs, design files, standards, projects, links and a FAQ. So have a look, the page again is here: http://www.freedomodds.com/music/echuck/ Keep on ChucKin'! Les (Inventor)

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Re: [chuck-users] Electronic ChucK
by inventor-66＠comcast.net 02 Oct '08

02 Oct '08

Thanks for your posts, folks, you're making this fun! I have completed the Power board and the ADC microphone board and I will put them on my website for you to download. The CAD tool of choice is Eagle, which is freeware for making small boards for educational use. Eagle is cross-platform to Windows and Mac, not sure about Linux but it might be. As a professional I used these types of CAD programs for 20 years and I can say that Eagle is a good one and I am enjoying the learning process. Regarding Spencer's topic of digital communication of analog signals, PICs are great at PWM and I2C. You can get a PIC chip for a few dollars US that has PWM and I2C modules, oh, and ADC also. Quite frankly, the main cost problem is the connectors which go for about 50 cents US per node. The PIC boards would not be expensive. I'm putting down footprints for the connectors and saying they are optional. Poor man's solution is to solder the interconnect and cut his cost in half. Poor woman's solution is the same, lol. let's be politically correct. No, poor woman's solution is to get a man to do the soldering for her, they are smart that way, lol. But I digress. I see each PIC processor not only functioning as a UGen, but also as a class. It's an encapsulated module with a clearly defined I2C digital interface, so treat it like a class. Different PICs access each other's private variables across the I2C and they share analog signals by PWM. To convert PWM to analog for interfacing from a PIC audio to an analog audio signal, we just use a passive or active low-pass filter module. To connect the other way we use the ADC input of the PICs. Regarding Kassen's mention of a ChucK interface, we can simply use the line-in jack for stereo input and the headphone jack for stereo output. If you have a soundcard then you can use that. Digital I/O can be done along these same interfaces. So yes, ChucK plugs into your sproingy mass of UGens and PICs. Since there appears to be interest, and I presume someday possibly actual board fabrication, I will begin a web page dedicated to EChucK. As time permits, I will put together some fun and interesting stuff to explore on the page. Does anyone have any suggestions about how to organize the page? I figure a title page with links to many topic pages. Cheers and as Ge would say, "Rock On!" Les (Inventor)

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Re: [chuck-users] Electronic ChucK
by inventor-66＠comcast.net 02 Oct '08

02 Oct '08

Kassen, Your point is well taken. I guess I'm not concerned about the audiophile quality of this system at all. If it's going to be so inexpensive then it will probably be inaccurate as well, and I'm OK with that. It's not intended to produce perfectly orchestrated audio, but rather to do something fun and interesting. Also, that 555 example was indeed for a variable frequency oscillator, more specifically a pulse position modulator from the data sheet. there is a CV input that stops the oscillator at ground and sets maximum frequency at Vcc. Though to get a 50% duty cycle one must add a flip-flop to the output. I'm really just going for a cool toy that will make lights blink and go woo-woo when I put together a ring of oscillators, this does not have to be super precise. That and the limited types of modulation input kind of make for a departure from ChucK, however. But that's OK too. It can simply be ChucK-inspired not ChucK duplicated. Les (Inventor)

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