Piezo elements (the round, gold-coloured bell-buzzer type) make excellent triggers. Drumpads like the Roland SPD-n type use these as the triggers. Modifications need to be done to create a reliable trigger. The mechanical integrity of these devices can be a problem: the leads can literally 'fall off'. I 'pot' mine in a layer of epoxy so that the leads are literally glued to the surface. The element can be glued to a rubber pad (this is essentially what Roland does) and mounted on a wooden block to create a trigger pad. Roland uses a small coil in series with the piezo: this is there to provide transient suppression as the instantaneous signal peaks can be quite high (albeit fleeting). This coil is a good idea as it protects the circuitry on the first buffer the piezo sees.
Other Piezo tips (mainly for audio): 1) If soldering new leads use a very low wattage iron, low temperature solder and complete the solder joint *quickly* 2) buy in bulk as a few will get destroyed as you perfect your method 3) if using for audio (i.e., as an audio pickup), then the piezo must be screened. A 'balanced signal' architecture works well here: piezo elements are wired 'signal hot' and 'signal cold', and the hum/RFI suppression is handled by a separate screen. 4) The MEAS film-type of piezo work much better for audio than the bell-buzzer type: http://www.meas-spec.com/product/t_product.aspx?id=2478 5) Impedance, impedance, impedance! Impedance is the rock upon which many piezo hackers perish. These elements need to be presented with an input impedance of many megaOhms. The average line input / mic input is totally inappropriate for these units. I use a simple FET buffer with an input impedance of 10 megaOhms on my piezos. Certain electronic DI boxes will also work well due to their high impedance characteristics, e.g., BSS. If piezos see a low-to-medium impedance, drastic LF rolloffs occur. This is why the cheap guitar contact mics sound so tinny when plugged directly into an amp. Rich Duckworth Lecturer in Music Technology Department of Music House 5 Trinity College Dublin 2 Ireland Tel 353 1 896 1500 It's the most devastating moment in a young mans life, when he quite reasonably says to himself, "I shall never play The Dane!" --- On Thu, 23/6/11, [email protected] <[email protected]> wrote: From: [email protected] <[email protected]> Subject: Pd-list Digest, Vol 75, Issue 88 To: [email protected] Date: Thursday, 23 June, 2011, 6:42 Send Pd-list mailing list submissions to [email protected] To subscribe or unsubscribe via the World Wide Web, visit http://lists.puredata.info/listinfo/pd-list or, via email, send a message with subject or body 'help' to [email protected] You can reach the person managing the list at [email protected] When replying, please edit your Subject line so it is more specific than "Re: Contents of Pd-list digest..." Today's Topics: 1. Re: control lot of audios files with arduino + puredata (FernandoG) 2. Re: Pd performance at TED (Tyler Leavitt) 3. Re: Pd performance at TED (Jonathan Wilkes) ---------------------------------------------------------------------- Message: 1 Date: Wed, 22 Jun 2011 21:13:45 -0400 From: FernandoG <[email protected]> Subject: Re: [PD] control lot of audios files with arduino + puredata To: Hans-Christoph Steiner <[email protected]> Cc: [email protected], Martin Peach <[email protected]> Message-ID: <[email protected]> Content-Type: text/plain; charset="iso-8859-1" Hi guys I was researching about arduino mega and pd firmata and i found a post where they say that its not posible to use all digital output and analog inputs of arduino mega. http://arduino.cc/forum/index.php?topic=62256.0 I gona buy arduino mega this week, but i need all inputs-output working for my proyect. Do you know something about this incompatibility?? thanks 2011/6/3 FernandoG <[email protected]> > Thanks guys, first i will try the easy way, arduino mega. > > best! > > > 2011/6/3 Hans-Christoph Steiner <[email protected]> > >> >> I think people have done some shift register+firmata things, but nothing >> got integrated into StandardFirmata/ Here's an example: >> >> http://www.makingthingsmove.org/blog/ >> >> .hc >> >> >> On Jun 2, 2011, at 1:02 AM, Martin Peach wrote: >> >> It's certainly possible to make a Pd patch that controls shift registers >>> through firmata. It's also possible to program the Arduino to do that and >>> send the switch numbers to a Pd patch that has a [comport] in it. >>> >>> Martin >>> >>> >>> On 2011-06-01 22:33, FernandoG wrote: >>> >>>> Thanks for answer >>>> >>>> Martin: I am researching about shift registers, but if the idea is to >>>> use puredata to control audio playbacks, thats means that i need to >>>> control shift registers with pd? because the arduino will be flashed >>>> with pd firmdata and will be imposible to upload code to control shift >>>> registers, is that posible or i am thinking wrong? >>>> Thanks again >>>> >>>> Best! >>>> >>>> >>>> 2011/5/30 Martin Peach <[email protected] >>>> <mailto:[email protected]>> >>>> >>>> On 2011-05-29 23:20, FernandoG wrote: >>>> >>>> Hi >>>> i need to design a sistem to control 40 diferents audio files and >>>> playback in a stereo sistem. I was thinking to use puredata and >>>> arduino, >>>> load the 40 audios in a pd patch and use 40 switches and >>>> resistors into >>>> some arduino inputs to trigger and playback any of the 40 audios >>>> in pd. >>>> Every switch will be conected to a diferent resistor to generate >>>> diferents voltages then arduino inputs can diferenciate witch >>>> audio to >>>> playback. Also i need to power on a led any time a specific audio >>>> is >>>> been playback. The 40 audios will not be playback simultanusly, >>>> but >>>> probably al least 15 or 20 could be. >>>> >>>> Anybody knows about a similar proyect? can i use analog input to >>>> control >>>> various samples or its not good idea? multiplexors? do i need to >>>> use an >>>> arduino mega or its not necesary?can i power 15-20 led >>>> simultaneously? >>>> the best way to do this system stable for long long time? >>>> >>>> >>>> The analog input method is similar to the resistor ladder that >>>> analog synthesizer keyboards used. Arduino analog inputs can >>>> differentiate 1024 levels but the values of resistors are usually >>>> 5%, but 40 levels should be easy. >>>> The best way to do LEDs is with shift registers. That way you can >>>> use just 3 pins on the Arduino to control as many LEDs as you like. >>>> For LEDs use parallel-output shift registers, like the 74HC164. Also >>>> the input could be done with parallel-load shift registers (for >>>> example the 74HC165), but the resistor method is cheaper. >>>> It should be quite stable over time. >>>> >>>> Martin >>>> >>>> >>>> >>>> >>>> _______________________________________________ >>>> [email protected] mailing list >>>> UNSUBSCRIBE and account-management -> >>>> http://lists.puredata.info/listinfo/pd-list >>>> >>> >>> >>> _______________________________________________ >>> [email protected] mailing list >>> UNSUBSCRIBE and account-management -> >>> http://lists.puredata.info/listinfo/pd-list >>> >> >> >> >> >> >> >> ---------------------------------------------------------------------------- >> >> "Free software means you control what your computer does. Non-free >> software means someone else controls that, and to some extent controls you." >> - Richard M. Stallman >> >> >> > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.puredata.info/pipermail/pd-list/attachments/20110622/060e7ec3/attachment-0001.htm> ------------------------------ Message: 2 Date: Wed, 22 Jun 2011 20:25:10 -0700 From: Tyler Leavitt <[email protected]> Subject: Re: [PD] Pd performance at TED To: Jonathan Wilkes <[email protected]> Cc: [email protected] Message-ID: <[email protected]> Content-Type: text/plain; charset="iso-8859-1" http://www.youtube.com/watch?v=DP_w_Mvh9tU Is this a technological parody? On Wed, Jun 22, 2011 at 2:57 PM, Jonathan Wilkes <[email protected]> wrote: > Yes, it's exactly like that. But that's the way the term was defined, > which-- as you > point out-- covers wide array of synthesis techniques and uses of digital > computers. > > I would just conclude that it doesn't seem a particularly enlightening > term, except for > a specific subset of parodies that have to do with technology. As a term > of derision > I think it's confusing/confused. > > -Jonathan > > --- On *Wed, 6/22/11, ALAN BROOKER <[email protected]>* wrote: > > > From: ALAN BROOKER <[email protected]> > > Subject: Re: [PD] Pd performance at TED > To: "Jonathan Wilkes" <[email protected]> > Cc: [email protected], "Cody Loyd" <[email protected]> > Date: Wednesday, June 22, 2011, 10:44 PM > > > > > On Wed, Jun 22, 2011 at 8:15 PM, Jonathan Wilkes > <[email protected]<http://mc/[email protected]> > > wrote: > > You're right, no one ever said that. Even me. > > Did you actually look at the patch? It is a technological parody of record > scratching. > It perfectly fits the definition given on this list. If you don't think > so, then > please tell me what you can do with that patch that's so musically > interesting that it > would warrant buying a modern digital computer instead of a turntable. > > > Well, one might want to connect the sampler patch to another patch that > produces a contrasting sound, they both would share the same values sent to > the atom to change pitches ect. > > Don't you think to say a patch that emulates scratching sounds from audio > samples is a technological parody of a scratching record player, is a bit > like saying a patch that emulates the sound of the piano is a technological > parody of a piano (they are both instruments)?. I think one purpose of audio > software to emulate instruments ? Regarding if it is musically interesting, > I'm v. sure you know record scratching is(was?) used as an instrument in hip > hop and such. > > If a purpose of audio software is emulation of physical instruments then I > don't think it should be labeled as a technological parody. Otherwise you > could use the argument 'why have a computer when I can buy a physical > instrument' every time? > > Just sharing thoughts really, interesting topic. > > > > _______________________________________________ > [email protected] mailing list > UNSUBSCRIBE and account-management -> > http://lists.puredata.info/listinfo/pd-list > > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.puredata.info/pipermail/pd-list/attachments/20110622/b1111355/attachment-0001.htm> ------------------------------ Message: 3 Date: Wed, 22 Jun 2011 22:41:57 -0700 (PDT) From: Jonathan Wilkes <[email protected]> Subject: Re: [PD] Pd performance at TED To: Tyler Leavitt <[email protected]> Cc: [email protected] Message-ID: <[email protected]> Content-Type: text/plain; charset="iso-8859-1" Certainly could be. :) Or on the other hand: http://www.youtube.com/watch?v=3cuuRG6-IT8 -Jonathan --- On Thu, 6/23/11, Tyler Leavitt <[email protected]> wrote: From: Tyler Leavitt <[email protected]> Subject: Re: [PD] Pd performance at TED To: "Jonathan Wilkes" <[email protected]> Cc: "ALAN BROOKER" <[email protected]>, [email protected] Date: Thursday, June 23, 2011, 5:25 AM http://www.youtube.com/watch?v=DP_w_Mvh9tU Is this a technological parody? On Wed, Jun 22, 2011 at 2:57 PM, Jonathan Wilkes <[email protected]> wrote: Yes, it's exactly like that.? But that's the way the term was defined, which-- as you point out-- covers wide array of synthesis techniques and uses of digital computers. I would just conclude that it doesn't seem a particularly enlightening term, except for a specific subset of parodies that have to do with technology.? As a term of derision I think it's confusing/confused. -Jonathan --- On Wed, 6/22/11, ALAN BROOKER <[email protected]> wrote: From: ALAN BROOKER <[email protected]> Subject: Re: [PD] Pd performance at TED To: "Jonathan Wilkes" <[email protected]> Cc: [email protected], "Cody Loyd" <[email protected]> Date: Wednesday, June 22, 2011, 10:44 PM On Wed, Jun 22, 2011 at 8:15 PM, Jonathan Wilkes <[email protected]> wrote: You're right, no one ever said that.? Even me. Did you actually look at the patch?? It is a technological parody of record scratching.? It perfectly fits the definition given on this list.? If you don't think so, then please tell me what you can do with that patch that's so musically interesting that it would warrant buying a modern digital computer instead of a turntable. Well, one might want to connect the sampler patch to another patch that produces a contrasting sound, they both would share the same values sent to the atom to change pitches ect. Don't you think to say a patch that emulates scratching sounds from audio samples is a?technological parody of a scratching record player, is a bit like saying a patch that emulates the sound of the?piano?is a technological parody of a piano (they are both instruments)?. I think one purpose of audio software to emulate instruments ? ?Regarding if it is musically interesting, I'm v. sure you know record scratching is(was?) used as an instrument in hip hop and such. If a purpose of audio software is emulation of physical instruments ?then I don't think it should be ?labeled as a technological parody. ?Otherwise you could use the argument 'why have a computer when I can buy a physical instrument' every time?? ?Just sharing thoughts really,?interesting?topic. _______________________________________________ [email protected] mailing list UNSUBSCRIBE and account-management -> http://lists.puredata.info/listinfo/pd-list -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.puredata.info/pipermail/pd-list/attachments/20110622/8c452e64/attachment.htm> ------------------------------ _______________________________________________ Pd-list mailing list [email protected] to manage your subscription (including un-subscription) see http://lists.puredata.info/listinfo/pd-list End of Pd-list Digest, Vol 75, Issue 88 ***************************************
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