MB808 build on veroboard

[Kanji]

Hello all,

 

First of all I want to thank this great site, I could not have done it without the information found here :smile:

 

I build couple of individual 808-voice boards couple years ago, starting with kick, then snare, and low tom drum.

 

When I first saw a MB808 video on youtube, I knew I have to have one.

This summer I thought why not build all the 808 sounds and wrap those in one case. Now I've build mid and hi toms, clave/rim, cowbell, hihats, maracas and clap. I'm still missing cymbal, but other than that, the clone works.

 

I used Eric Archers circuits on Kick, Snare and Hihats, and love how those sound. To make toms and other sounds, I transfered original schematics to veroboard design. First tom circuit took couple hours to solder, but three days to troubleshoot :D  Luckily, when I got it working, mid and hi toms are basicly the same circuit, just using different values on some capacitors and resistors.

 

Cowbell and rimshot/clave circuits were easy, but clap circuit sure gave me the hardest time.

After finishing all the sound circuits I needed a trusty sequencer, so that I have a standalone unit. After gathering some courage, I ordered midibox core, din and dout kits from SmashTV and started building the sequencer. Sequencers main UI pbc with all the buttons and leds are also build on veroboard. I have to say, figuring out connections and connecting all the buttons and leds to Midibox DIN and DOUTS was lot of work, but it was all worth it because MB808 sequencer firmware is simple amazing.

 

I didn't want to reinvent the wheel, so when it came time to do a front panel, I drew a panel using Moogah panel as a template, so I want to thank him also.

Here are couple photos from the build and video so you can here sounds and see the sequencer in action.

 

Its still work in progress, but since taking the pics, I've build individual outs and main LEVEL amp section, so basicly its done apart the cymbal.

It has ugly insides but beautiful soul

 

Edited September 14, 2013 by Kanji

[niklasni1]

That is impressive! Excellent work!

[Altitude]

impressive.  Quite an undertaking..

[zephyrin]

Could you tell me how you are connected the Accent input on the 808-voice board ?

Edited September 20, 2013 by zephyrin

[Kanji]

@zephyrin :  I've build all the sounds on their own boards using eric archers 808-clone schematics and original schematics.

 

All these boards have their own TRIGGER IN, which is just transistor circuit triggering the module, everytime it senses trigger voltage between 1V to 5+ volts. Each voice boards have also ACCENT IN, which basicly is voltage control for the circuit.

 

MB808 schematics have ACCENT Circuit which feeds voltage to sound modules ACCENT IN. If you don't want to use accent, you can simply tie each circuits accent in to 12V or what ever you VCC is.

 

So to put it shortly, I've connected all the trigger inputs to corresponding trigger outs on Midibox DOUTs. There was a mapping of DOUTs and DINs on another MB808 thread here.

[zephyrin]

He tank you for your answer i have a 808 like you but with the microlarge PCB

 

My sequencer don't trim nothing but i have no connection for the input accent perhaps this is the reason that don't work ?

 

  

[sneakthief]

No accent = no trigger on an 808

[sbm]

Wow awesome builds!

[Kanji]

He tank you for your answer i have a 808 like you but with the microlarge PCB

 

My sequencer don't trim nothing but i have no connection for the input accent perhaps this is the reason that don't work ?

 

Does your 808 work / make a sound at all?

 

 

I took a look at Microlarge 808 PCB's and it seems that there are two connections on each sounds trigger connector.

Trigger and Accent connections are side by side at same connector.

 

All the 808-clone sound modules and circuits that I've come across have both TRIG and ACCENT inputs. If you dont want to use accent, or if you dont have accent circuit to operate accent, Accent input is tied to 12volts, or what ever your VCC is.

 

More info from here -> http://ericarcher.net/wp-content/uploads/2009/07/tr-808-bass-drum-diy-project.pdf

 

"f you are planning on triggering the circuit from a logic signal, the easiest way is to tie ACCENT to +12V (+15V), and connect

the logic signal to TRIGGER. This schematic includes my diode - cap - resistor network. This makes trigger behavior independent of pulse width (unless the pulse is super short of course)"

 

 

If your ACCENT input doesn't have voltage/isn't connected, circuit doesn't make a sound.

 

I put a picture of Microlarge PCB so you can see what I mean. Trig needs to be connected to to Midibox DOUTs pin that supplies the trigger for the bassdrum, and Accent needs to be connected to +12V (or what ever the positive voltage is on your powersupply)

 

EDIT : I DO NOT TAKE ANY RESPONSIBLE FOR POSSIBLE DAMAGE, because I'm not 100% familiar with microlarge PCB's, but looking at the pictures, I would assume that it operates exactly like every other 808-sound circuit that I've seen. Trig = for trigger pulse and AC = for accent voltage.

Edited September 23, 2013 by Kanji

[zephyrin]

He thank you for your answer

 

When i have tested my MB808 i haven't put nothing on the AC input and now i understand why i have no sound i will trying this as soon.

[sneakthief]

Hey Kanji - do you have a document which lists the DOUT and DIN connections? That would be amazingly helpful for people trying to recreate what you've done here!

[Kanji]

Hello sneakthief, I noticed your post at muffwigglers Yocto thread :smile:

 

Here are the files that I used for connecting DINs and DOUTs. I'm not the author of these files, I just found them from older MB808 build thread, hope these help.

 

Both files are really useful, but I think I build mine mostly relying on the later one, the MB808 drumseq pinout file.

808 hardware config.pdf

MB808 drumseq pinout.pdf

Edited October 30, 2013 by Kanji

[spotta]

Many thanks Kanji

These will come in handy for me as well.

[sneakthief]

Thanks Kanji! That's true synth-DIY spirit :)

[xpmtl]

Hi Kanji,

 

Did you altered the pinouts in the firmware and compiled a new one or did you use 6 Shift Registers for the Dins?

 

MB-808 on eight-o-eight website only use 5 SRs so it's a bit confusing...

 

Thankies

[Kanji]

Sorry for late reply.

 

I used MB808 setup thats explained at uCapps webpage. Uploaded MB808 firmware as it is and connected DINS and DOUTS like mapped on those charts I posted.

 

I build mine using this setup and bought PCBs and KITS from SmashTV :

• 1 x MBHP_CORE, stuffed with PIC18F4620
• 2 x MBHP_DINX4 (only 6 74HC165 shift registers used)
• 2 x MBHP_DOUTX4 (7 74HC595 shift registers used)
• 1 rotary encoder (for tempo, could also be used for additonal purposes in future)
• 33 buttons
• 35 LEDs (33 could be integrated into buttons, 2 additional LEDs to display selected layer and record mode)

 

Edit : Originally I tried to figure out DIN and DOUT connections from midibox 808 schematics, but I was also confused by those. Just use the charts I posted couple posts ago, it worked for me :smile:

Edited November 6, 2013 by Kanji

[Kanji]

Here's some video action from my MB808.   Adaptation from Plastikmans Spastik :

 

 

edit : I'm still in search of those colourful rainbow switches for the sequencer. So if someone knows a place where to get those, without need to purchase a bulk load, I would be forever greatful.

Edited November 29, 2013 by Kanji

[zephyrin]

Hi Kanji velleman make all color digitast

 

http://www.velleman.eu/products/search/?q=digitast&search=Recherche

 

http://www.velleman.eu/products/view/?id=2753

 

for exemple the ref for red with red led is SP86-A2-1-1

 

yellow with red led is SP86-A2-2-1

 

With google and the ref it will be  easy to found a seller ....

 

It s also easy to change the led

[Morelius21]

Hi 

 

i like to build the md808 with microlarge pcb.i have problem to understand the digital section.

 

I read this post but i don't understand the pdf. Can somebody explain this please?

 

MB808 drumseq pinout.pdf

 

808 hardware config.pdf

 

thanks

[jaytee]

Sorry to revive an old thread but I was just curious... kanji, do you have your veroboard layouts available? Been thinking about doing a clap circuit on veroboard but it'd be nice if I could build off of your work.