selfservice

I've bought on ebay a bunch of old audio boards to finish my MidiBox FM. there was an audio board with only one digital chip, the YMF711, having the opl logo stamped on. i've found the datasheet (14MB x 44pages :o ), and i think it's a very complete and powerful solution for a syntetizer. check it out, i'm ready for developing if i find someone interested and ready to give an hand!

yes, it's a dac problem. i've changed the YMF262 and the result is the same. i've noticed a thing may be useful for other debugs: the YMF262 without the core module attached sends random pulses on the dout pins, with the core module and the testtone firmware sends regular pulses. maybe useful for checking good connections between modules. i'm going to quadruple check the layout and the values, but the voltages on the pins seems good... bah...

wow, building complete, i've got some kind of prototype on my bench. but the troubles is behind the edge... ??? all connections doublecheked 16458 times, lastest version of bootloader and mios burned in the pic the application is testtone. the lcd writes "OPL3 Testtone" and nothing else, nothing at the outputs. the crystal works, the slave clock output of the '262 works, the '262 sends some kind of signal to the DAC but nothing on the outputs. i'm going to check all signals on all pins, but i think my '262 was fried during desoldering. any suggestion?

hi guys, many thanks for your interest in my work... of course i post all the files (schematic, copper side and assembly top) as soon as the prototype were working! soldering ICs on the pcb reduces the noise, and give a better look to the assembly, and soldering ICs like the TL074 is just a joke, it's nearly impossible to blast souch chip due to overheat. i had such results with a made in cina soldering station @ 300°C and 0,5mm Sn/Pb/Cu soldering wire.

finished! there is the power supply also, 2 sections, one for analog part e another for digital supply. i hope to test this in the next days.

here is some photos of the pcb: after etching, before drilling: after drilling (with a dremel!), note the perfect alignment that such type of small hole in the copper can offer!: the bottom side with the OPL chips: the top side, some stuff is missing:

Hi, after a succesful build of a small midibox64 i'm trying with the FM synth. i've downloaded the schematic and the pcb for building the OPl3 Module but i've experienced some troubles: frist, eagle makes the inner hole of the pad too big, the result is an headache when trying to center the drill ;D second, some holes, expecially for the jumpers, are very small, drilling and soldering results difficult. third, i "hate" eagle ;D so i've made another pcb using some cad a bit more complex than eagle, the attachment is the result. i've take care expecially for ground plane and to make shorter the "hot" traces. i'm going to etch the pcb, the hope is to get the frist prototype working in the next days. please, leave your comments 8) opl3v2.pdf opl3v2.pdf

i have to try... if it will offer sufficent precision i'll be very happy if not i have to try in analog way :( :( ???

it's possible to linearize some of the analog inputs via software to attach some log pots?

expecially for syncing beat to light, it it isn't very performant if done via analog filters or via microprocessor but an fft (fast fourier transform) inplemented on a pc that can comunicate via midi to the consolle, and the consolle activate the lights in beat synced mode maybe a fantastic thing. I think the 50% of the "enjoyng" of the dancefloor is due to the music synced light show.

hi, i'm playing with a midibox64 (I hope to have it working for the 31 dec.) and i had an idea: i was tinking for a long time to a dmx consolle, but now i'm thinking to modificate mios to make it compatible with dmx standard is maybe possible to assign some pots to dmx and other to midi, having a single consolle for playing music and lights... of course another usart is needed, and it must be very fast, dmx travels at 250kbit/s. what about another uart (maybe another microcontroller) via I2C? what do you think about this? Thorsten, do you think it's possible?

more stuff mounted!! ;D now with a photo of the rear side of the panel: i'm waiting for leds and pushbuttons to cover the other holes ;)

on the case is written: 50KA x 2 6236 near the frist line there is two symbol, a triangle with the marked edges and a circle with an "A" inside. that's all.

i have about 130 of these it's 2x50k A (stereo) sliders, good and very precise movement, is good for both pcb or wire soldering. i sell this 2€ each.

the faders are 2 x 50K A sliding for 55mm. i can sell them for 2€ each but i have to check for shipping cost.

There is the tool used for cuttin the panel, at 33000 rpm is a bomb with the Al, better than working on wood. now is time for electronics: This is the power supply, it was mounted on a lan switch This is all the electronics, but i need to build another two DIN and DOUT modules. this i the faders I used, I have about 120 pices, I fortunately can't use all of this so if you need some pots I can sell :

yes, I've draw he panel with a cad, printed in 1:1 scale on many sheets (like an A3 made of many A4 sheets), and glued on the panel. so i have made the holes and cutted the alluminium with a special aluminium cutting tool on my dremel, it's like cutting butter. but some adjustment with an abrasive tool ( i don't know the name in english, in italian is "lima" ) was needed. you can see some pushbutton square holes before and after the cure. that's all, it wasn't difficult, and the result is good. :D I've asked for laser cutting but it was about 100€ :o :o I'm thinking my english is very bad...

Hi, I've finished the front panel (some adjustment is required) and I started to mount some stuff. There is an image. http://img510.imageshack.us/img510/2999/p10100021wy.jpg What do you think about?

but with this i can't use pots... i'm thinking about two midibox in series, but i need two lcd's, or using some unused analog inputs and a voltage divider to drive multiple pushbuttons on a single line. but i have no idea how to tell traktor dj studio to learn this last solution.

is possible to use 128 buttons instead of 64 in the midibox 64?

is possible to use 24c64 instead of 24c256 in the bankstick? i'm asking this because i have a lot of these chips ;)

and the core of the A&H Xone 92??? I hope the case of this wonderful midibox is only temporary, or a fantastic mixer will be decapitated ;D

Hi, my name is Stefano from Italy, I'm a dj and i'm now using Traktor dj studio, 2 Gemini xl500 turntables and a Behringer DJX700 mixer. the main trouble I'm experiencing when mixing a Traktor mp3 and a vinyl is the tempo and pitch syncing because the keyboard that don't offer too much sensitivity like turntables pitch fader. So I've decided to start building a Midibox64, Traktor dj studio consolle like. This is a preliminary design of the panel, I have some indecision about the bottom part of the consolle but i think probabily it's definitive: what do you think about this? who have some modifications to this design to improve funcionality before i start building the panel? thank you everybody for the fantastic projects (I'm planning to build a OPL3 synt) and for the support !!

forse xche devi connettere tutti i pin inutilizzati degli ingressi analogici a massa, se no parte un mucchio di traffico midi.

anche io posso fare i pcb x le midibox ulteriori informazioni a ste_@inwind.it