A switch controller idea?

[CarpathianBreed]

I´m pretty sure the topic has been went through before and if so, and somebody knows where to find it let me know. But here it goes.

Lets start with an idea of a contoller with 16 pads, one switch for each pad. The switches would close when struck. There would be a common low level voltage source that would have been wired to all 16 switches. the voltage fed to the switches would be brought down by say, resistance.

These next voltage amounts are just for an example, because I´m not aware of what kind of AC signal megadrum is built for.

So if a regulated voltage source would put out 1V and this would be the max voltage/max output/max velocity, it could be lowered down so each of the 16 switches would pass through a different voltage output when closed. 1V/16=0,0625V would be the voltage for the first switch, 0,125V for the second switch and so on till the 16th switch that would pass on a voltage of 1V.

This could then be fed to Megadrum and have it understand these voltages as different velocity levels of same input. Then this information could be passed on to a software sampler that can layer the samples assigned to different input velocities.

Not a drum thing necessarily but one could theoretically build a contoller and have it contol samplers and commands in a DAW for example with just one input in the module being used.

I assume the the piezo puts out very low voltage of some mV and very low current of some µA, so the real issue would be to succesfully apply wanted voltages. So at this case the count of the pads/switches would probably be be lower for a single input.

Does this make any sense? Ideas?

K

[airflamesred]

I like your thinking mate but this can be done in most samplers (Kontakt etc) and to a certain extent with MD itself. I have cymbals wired to 2 MD inputs which I'm hoping to send a note and trigger an automation track.

[CarpathianBreed]

I like your thinking mate but this can be done in most samplers (Kontakt etc) and to a certain extent with MD itself. I have cymbals wired to 2 MD inputs which I'm hoping to send a note and trigger an automation track.

Yes, most soft samplers do this. But my main "question" was on the technical side. Like what is the voltage region that a piezo transducer works. I try to think of something else to extend the megadrum features. Like 56 inputs wouldn´t be enough.

The main idea was not to have just random samples being played when you hit a cymbal. Altho I think one could play specific samples is one masters hittign a cymbal on 127 different velocities.

I think the idea of using one or two inputs to access a couple of dozen commands would be welcome in any household.

At the end of the day it´s just a question of working within safe limits that guarantee that the module will not be harmed.

K

[Wapata]

As an answer, I have questions: doesn't a piezo cost something like 1-2 € and a switch too ?
Is there a mechanical limitation for you to not put a little piezo ? Will you use micro switches ?

... Are we talking about a drum device, or an other thing ?

[CarpathianBreed]

As an answer, I have questions: doesn't a piezo cost something like 1-2 € and a switch too ?

Piezos are low cost. So are the switches, this is not an issue at all.

Is there a mechanical limitation for you to not put a little piezo ? Will you use micro switches ?

No mechanical limitation. The idea is to basically have many switching inputs that can be routed to just one megadrum input. And with those switches the voltage passed out to megadrum would be always the same. As with piezos you determine the output voltage with the hit velocity. And I´m not a engineer enough to see a way to use multiple piezos in same input and have each of them do a spesific task. I know a module like megadrum has 56 inputs so that´s quite a lot from the get go. But I myself bought the 56 input version for a reason. And I don´t think I would waste some 16 inputs to just controlling a DAW or launching samples at few occasions. Those have a better use in a Drum Kit.

... Are we talking about a drum device, or an other thing ?

This can be anything one wants. In the end of the day it´s just like any non-dynamic controller. But I´m thinking one with pads the size that you can hit with drum sticks while playing. Of course you can buy Alesis and Roland sample pads but what´s the fun in that.

K

[Wapata]

If you can use an other midi device, you may find one here:
http://www.sonelec-musique.com/electron ... _midi.html
I'm thinking about Contrôleur MIDI 003 - 128 boutons-poussoirs, 1 sortie MIDI OUT, génération de notes MIDI, avec PIC 16F628A.
You may find something like this ready to use but with big prices on the net if you don't want to solder. http://www.midiboutique.com/MIDI-encoders
Finally, it's like a midi master keyboard, but naked.

[CarpathianBreed]

If you can use an other midi device, you may find one here:
http://www.sonelec-musique.com/electron ... _midi.html
I'm thinking about Contrôleur MIDI 003 - 128 boutons-poussoirs, 1 sortie MIDI OUT, génération de notes MIDI, avec PIC 16F628A.
You may find something like this ready to use but with big prices on the net if you don't want to solder. http://www.midiboutique.com/MIDI-encoders
Finally, it's like a midi master keyboard, but naked.

Sorry, But this really has nothing to do with what I´m trying to figure out. If I wanted a midi controller I could just buy one. Or take an old keyboard and rip it apart and use the encoder inside. But this thing I´m gathering information for has nothing to do with midi itself.

What I need to know is what is the voltage range piezo element puts out voltage as a trigger used with megadrum. And the current. I don´t have an oscilloscope at hand so I´m not able to reliably measure it myself.

K

[dmitri]

Unloaded piezos can produce up to ~40-50V output signals. When loaded the voltage will be much lower depending on load's impedance.

[CarpathianBreed]

Unloaded piezos can produce up to ~40-50V output signals. When loaded the voltage will be much lower depending on load's impedance.

Thanks Dmitri!

Can you say anything about the safe voltages? Like what are the voltages/current safe to feed to megadrum as pulses mimicing a piezo action? Or is this possible?

K

[dmitri]

It's safe to feed piezo signals to MegaDrum. It's not just voltage, it is also combination of source (piezo) and the load's (MegaDrum input) impedance. When loaded onto a MegaDrum input, piezo signals are considerably reduced.