NANO-8 DRUM TRIGGER KIT..

[Jdansti]

hi sam,

no issues at all..

if you was building pads for hitting hard with sticks, then they would
obviously have to be quite tough...and thicker to get a good velocity sense out of them..soft/hard etc
you could even just hook up proper e-kit pads to it too...so its just a drum brain.
all the research i did showed that all kits are merely piezo triggers anyway...just with 1/4'' jacks
i just wanted to keep this small, and portable..so went with the DC socket /plug route..neato.

any unused inputs are switched to ground, otherwise any 'open' ones would cause mis triggering..


the piezos are very sensitive..but i havent had any 'breakup' if thats what you mean..

You could probably use a used game drum kit that already has the built in piezos like this:
http://www.ebay.com/itm/Band-Hero-Wireless-Drum-Kit-Controller-for-PS3-XBOX-360-/121977564315?hash=item1c666dec9b:g:-NAAAOSwrXdXK1mD



There's a kick pedal, but it might only be a spst switch. You'd have to have to simulate a piezo by sending a small voltage when the switch closes.

[deadastronaut]

@mick, yeah man, came out great, thanks to you and your help....cheers man. 

@karbo:  yeah the min/max velocity can be set in the code.... i guess 64 would be in middle range..

@quacksed: cool...i went with the small build so i can throw it in a bag and off i go...its very cool..

@john, yes they are the same piezo triggers...i tried a rock band kick, and it worked ok, that was piezo too and just covered in thick plastic, it worked fine, but it wobbled from side to side too much..
as for the midi side of some of those games kits , you have to use a serial midi programme, and that introduces latency...pretty badly... theres no lag at all with the nano..

my mate came over last night, and he gave me a set of sticks, so i'll be trying out full size
whackable pads with it...handy as i'll only have to test one and get that right...

[anotherjim]

That's cool kit. Well done Rob.
Right before xmas I'd pretty much finished the code for a drum trigger in an AVR mega328. But I've only given it 6 channels so each can have a velocity pot (only 6 adc inputs and I didn't want too much stuff outside the chip to expand that). I spent most of the code design arguing with myself whether or not to send proper note_off messages or, what most projects opt for, zero velocity note_on's. I decide to send proper note_off's instead. I intend to add, but may not get around to it, midi clock and start/stop messages.
Mine is intended for a switch panel step sequencer (2 out of 6 tracks built so far) as I'm hopeless with drums, but with the right external bits, it would work off pad triggers. Funny, I can play a simple groove on guitar, keyboard or bass until the cows come home, but I can't play drums for more than a second without totally losing the plot. But with a switch sequencer, and step switches for every sound, I can play with the rhythms while it's running and never get out of time!

[deadastronaut]

sounds like a cool project man..

i may have to give a sequencer a go one day...

once i catch up with the other 1000 projects whizzing around my screwed up head 

[karbomusic]

@karbo:  yeah the min/max velocity can be set in the code.... i guess 64 would be in middle range..

Would that cover instances of poor incoming signals? I'm thinking of old school trigger brains where you could control the gain/sensitivity of the piezo itself. I suppose it covers it somewhat, I can test it myself, just a curiosity.

[deadastronaut]

hmmmm not sure on that...

i did experiment with a pot across a piezo, which was interesting...

it worked on cutting the sensitivity...adjustable.

but i ended up leaving that...

[slacker]

Would that cover instances of poor incoming signals? I'm thinking of old school trigger brains where you could control the gain/sensitivity of the piezo itself.

You can set the minimum threshold level in the code, signals below that are ignored, you can set this per pad so you can reject noise and crosstalk from other pads. You can't control the gain or sensitivity in the code, you can set the maximum midi volume globally but that just "clips" signals at that level. It might be possible to add an offset or multiplier to give some gain control. There's also no reason you couldn't build a fancier front end for the piezos if you wanted to,

[karbomusic]

Would that cover instances of poor incoming signals? I'm thinking of old school trigger brains where you could control the gain/sensitivity of the piezo itself.

You can set the minimum threshold level in the code, signals below that are ignored, you can set this per pad so you can reject noise and crosstalk from other pads. You can't control the gain or sensitivity in the code, you can set the maximum midi volume globally but that just "clips" signals at that level. It might be possible to add an offset or multiplier to give some gain control. There's also no reason you couldn't build a fancier front end for the piezos if you wanted to,

Yep, that's what I meant. No use overdoing it, just thinking out loud. I can test some stuff later on one of my Nano/Micros. Just round out the sensitivity control and add pitch-to-midi and you've got yourself a guitar midi controller.  (half joking)

[stallik]

Thought I'd necro this thread as I've just boxed up a Nano 8

Works fine - hardly suprising as Rob did all the work on this but I thought I'd change the led colours. Started with Green/Blue for On/Midi but the green was far too bright. today's delivery of some proper pcb standoffs prompted me to change the green for a diffused red. Bit of a pain as I'm having to fit the led's to the box, feed the leads through the pcb and solder when i'm done.

Unfortunately, the diffused red turned out to be a super bright white! as I's managed to get everything lined up so well, I'll just live with it....



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[garcho]

nice work Rob, love seeing pedal peeps non-pedal projects here, working on a motorized MIDI DAW controller right now

[deadastronaut]

Looks great kevin,   hope you had fun filing the long rectangle...as i did. 
Makes for a neat lil kit though, well worth it...

gary, yeah took a while, but with help fom mick ice9, and slacker
got it up n running as it should...

Motorized midi...faders?

[Ice-9]

That is looking pretty mean in what looks like metallic black, nice build Stallik   

[stallik]

Thanks. Dark Grey - BMW graphite sparkle from Halfords. Tend to chip after a while, probably poor preparation so I sanded this box like it was going to be etched. Time will tell if it makes a difference.

[Beo]

Nice job DA!

Quick side question, hopefully not to derail... any way to synth a few drum sounds directly from the avr chip (kick and high hat maybe)... and not have it sound all atari?

Alternatively, anyone recommend a basic small form synth drum machine that could be triggered by this doodad?

Thanks! Travis

[deadastronaut]

Travis, this is just a midi trigger, so you assign your midi drum/synth notes to each piezo....
/dc socket...for use with a DAW KIT...EZdrum,  mkpowerkit etc etc...

avr....no idea, way over my head...

For live use you could get an old drum machine and tack 2 footswitches to 2 pads i guess...
but then you would lose velocity control...but it would work as an instant cheapo result...

[neufena]

Hi,

Sorry if I shouldn't have posted on an old thread. I've built this kit to use with an old broken Yamaha DD9.  It's working however anything other then the lightest tap generates ghost triggers across other pads.  Any advice on what I can do to prevent this?

Thanks,

[deadastronaut]

hi, they need to be isolated from each other...

i had metal disks with the piezo's glued to them,  and had foam under them.  worked fine.

look up making your own drum pads for ideas.

[neufena]

Sorry I didn't explain fully.  I have unsoldered all but one pad for testing and monitor the midi output. When hit I get several I get several different midi notes.  So it's as if one pad is somehow triggering multiple inputs.  The harder I hit the more other notes are triggered. A light tap and it's just the correct note. A harder tap and it's the correct note and the next pad's note.  A hard hit and I get many different notes.

[deadastronaut]

do you have the dc sockets installed?, these will send the 'unused' 'unplugged pads to ground when unplugged.

if not then yes they will mis-trigger...

i suspect this is what is happening .

[neufena]

No, I'm not using sockets, I wired the pads directly to the PCB.  Sounds like this is what's happening.  I'll try grounding the unused pads (the DD9 only has 4) and the other 4 are currently not connected (eventually I'll add sockets to allow expansion). Thanks