Making an Electronic Drum Module..

[Peter_wadley]

Hi,

I know there are alot of talented electronic enthusiasts on here, so lets see your problem solving skills on this one

Basically Ive been in the market for an electronic drum kit.. however I am tight on money due to school savings..

Ive been looking for a Td-5 or Td-7 drum brain by Roland..

The module that the triggers are hooked to is what I would like to make

As you can see by the video these devices take vibration from these triggers and output the sound of drums. One drum sound per trigger..

The price these are going for is outrageous.. $500+!

I would like to make my own.. if it is reasonably possible and CHEAPER then giving into eBay.

So basically I will have 5 triggers all connect to the homemade Module with 1/4'' plugs.

I need to come up with a way to take the signal from the triggers and make them play 5 sounds .. one per trigger:
1 snare
3 toms
and one bass sound

The sounds NEED to be able to play over each other!

Also, the volume of the drum sounds will need to be proportional to the velocity of each hit on the triggers. (thats going to be hard im sure)

I know this is probably going to be a hard project but I am determined to materialize it.. $500.. pff not on my watch.

My starting project specific materials are:

-5 triggers
-5 1/4'' input jacks
-1 1/4'' output jack
- power supply = check
- any misc. components = check
- special IC's (I know I will need at least 1) can be purchased

Also, I know these modules have like 512 differents sounds .. chorus.. reveb and all that..

Im just looking for 5 sounds making up a normal acoustic drum kit, nothing special.

 

[Nigel Goodwin]

You're possibly looking for 30 to 40 year old technology, drum sounds used to be generated using gated white noise and filters, with tuned, not-quite oscillating filters, for bongos and such.

But these types of systems didn't really provide a very convincing sound, and you'll notice that drum machines often include an 'electronic drum' sound as well.

Anything remotely modern simply uses a recording of a real drum, and plays the samples back as required. Most keyboards have drum effects, again simply recorded samples, you might consider a cheap midi keyboard and use that to create the drum sounds.

 

[Peter_wadley]

I have found exactly what I was looking for!!!!

I think all of you PIC users are going to enjoy this..



Its basically what I was looking to build.. The heart of the setup is the
PIC16F877.

Basically, the signal from the triggers are sent through an opamp (each having its own).. These signals are then feed through the 10bit Analog/Digitial converter from the PIC16F877.. the signal is then sent through a Serial port and the drum sounds are played through a PC or it can be sent through an MIDI port to ..well an MIDI.

As for programming the 16F877.. I notice ic-prog is down lately.. Im look for a plain & simple JDM programmer I can make to use with IC-prog.. Does anyone have any links or schematic they can send my way?

Im definately going to be making this eDrum.. anyone else intrested?

 

[Blueteeth]

Yeah, anything MIDI lends itself VERY well to microcontrollers. Most have an on-board UART to send/recieve MIDI msg's (I'm working on a USB version meself). The creator of 'edrum' I believe also created the midibox thing (www.ucapps.de ?), nice bloke, very open, and very clever. The hard part for that is making the drum heads from scratch, but most seem to buy them, or modify cheap practice pads for use with piezo triggers.

As for sampling the triggers, you may want to use a sample-hold type circuit, so that each trigger, raises its output, but stays at maximum, until the PIC has time to read it via its ADC, then the S-H is reset.

About a JDM programmer, I built this one, and it served me well for over a year: **broken link removed**

Easy stripboard layout, and it worked first time. You might want to add a ICSP header to it though for programming bigger PIC's (its socket is only for 18 pinners).

Always note that, with projects like edrum, what seems easy at first, can soon baloon up into a massive project of sourcing parts, designing stripboard/PCB's, and enclosures. The number of times I've calculated the cost of parts to be about 1/3rd of what they actually were after completion.

Good luck, and happy drumming Once I have my kit setup (stil need to find a decent cheap frame) I'll hopefully add it to a website, along with some terribly executed drum solo's.

Blueteeth

Edit: Corrected URL. My memory is terrible.

 

[Peter_wadley]

Yeah, anything MIDI lends itself VERY well to microcontrollers. Most have an on-board UART to send/recieve MIDI msg's (I'm working on a USB version meself). The creator of 'edrum' I believe also created the midibox thing (www.ucapps.com ?), nice bloke, very open, and very clever. The hard part for that is making the drum heads from scratch, but most seem to buy them, or modify cheap practice pads for use with piezo triggers.

As for sampling the triggers, you may want to use a sample-hold type circuit, so that each trigger, raises its output, but stays at maximum, until the PIC has time to read it via its ADC, then the S-H is reset.

About a JDM programmer, I built this one, and it served me well for over a year: **broken link removed**

Easy stripboard layout, and it worked first time. You might want to add a ICSP header to it though for programming bigger PIC's (its socket is only for 18 pinners).

Always note that, with projects like edrum, what seems easy at first, can soon baloon up into a massive project of sourcing parts, designing stripboard/PCB's, and enclosures. The number of times I've calculated the cost of parts to be about 1/3rd of what they actually were after completion.

Good luck, and happy drumming Once I have my kit setup (stil need to find a decent cheap frame) I'll hopefully add it to a website, along with some terribly executed drum solo's.

Blueteeth

Thanks Blueteeth, it's been appreciated.

I think I will make the programmer you have linked.. thanks

As for making a decent cheap frame.. have you considered pvc piping?

 

[Peter_wadley]

Just reviewing the programmer and noticed it says that it is limited to the
16f8x series

I need one for the 16877 chips (40 pin DIP)

 

[Nigel Goodwin]

Just reviewing the programmer and noticed it says that it is limited to the
16f8x series

I need one for the 16877 chips (40 pin DIP)

Just wire a 40 pin socket instead of the 18 pin one!.

The edrum you're looking at doesn't make any noises, it simply feeds midi to an existing instrument (or a PC), is that what you're looking for? (it wasn't what you asked).

 

[Blueteeth]

I've used the uJDM on every PIC I have (admittedly only the 12,16 and 18F series) and its slow as hell compared to my PICkit2, but it does the job when I'm stuck. I don't do sockets really, just add ICSP headers to all my apps (one off's), but you could make an adapter board, with all PIC sized sockets, 40pin included (as nigel suggested).

Also, I didn't completely read your first post, nigel is right, edrum will not produce any sounds itself, only trigger signals from your DIY drum kit. Aside from using a PC with softsynths you're really limited in stand-alone hardware synths for drums. It would be a pretty advanced project to design a DSP platform, that plays pre-recorded samples on each trigger, lots of multiplcation, and addition/filtering there. (all that and the quality of the samples are why those things are so damn expensive).

For soft-synths, either free progs, soundfonts, all the way up to the 8 grand suite software with every kit ever made sampled millions of times. Saying that, plenty of music nowdays uses the 'ol roland/yamaha drum synths. Completely synthesised, so it won't sound anything like an 'woody' kit, but you could relive any 80's/90's pop Even that would be a mamoth project, as they're horrendously complicated.

Anyway, mini-rant over, theres plenty of freeware floating about on the web that will produce half-decent drum sounds from midi. I used soundfonts from www.hammersound.net, along with a free soundfont player to test my 12F675 midi bongo's. - A typical half-arsed blueteeth thing to do.

Blueteeth

 

[Peter_wadley]

Ok,

Im going to make that JDM programmer w/ a 40pin socket..

Also a side question:

Im going to buy the pic16f877 from digi-key.. it is $9.50CDN do you think I could find a better price.. I know buying in such low quantity is always more expensive though..

Yeah im aware the eDrum only converts the analog hits of the triggers to digitial MIDI signals..

Which MIDI program should I use blue?

Im looking for the best.. FREE ... program I can get.

Making a full fledged roland replica would be VERY hard work.. eDrum is all I need.. no gigging here.

Peter Wadley