SounDuke

Well found encoders at Smash shop :D How to proceed in detents elimination surgery?

Hi everyone, I'm searching for cheap non detented encoders (not more than 1.50 € each). The ALPS STEC11b01 available from distrelec cost 5 € (!). I'd like to replace pots with encoders, so I don't need detents, does anyone know where to find them? I'm almost sure the quadroubled resolution isn't useable with detented encoders (which are cheaper)

Hi everyone, Is the scanning matrix supported in MB64 app or it can be used only with the SM example under mios download?

Hi everyone, could I upload on one pic the MB64 app and then midi chain that core with the second one stuffed with a pic and MBLC app? my objective is to have 8 motorfaders to control Ableton Live mixer and 64 pots for general purpose. Is it possible? And do I need a double power supply for MFmodule and the cores or I can use a single 12V one (will the 7805 get too hot?) thanks in advance

Sure as soon as I can I'll draw a schematic. In the meantime, I'll try to explain how it works. The rubber switches (each set is a 11 switches rubber stripe) are positioned under the standard plastic keys (the black and the white ones :D) in little holes carved in a plastic structure. Each rubber switch stands over a contact on the printed circuit, which is screwed very near to the plastic structure with the holes, and connects the lines to the row. when a key is depressed, the rubber switch activates the contact, the current flowing through the contact changes depending on how much the rubber is compressed, so that the switch works as a variable resistance. However, it will be clearer as soon as I find the time to draw schematics. Thanks for the interest Thorsten, I'll post photos too

As stated in the midi controller topic in design concepts, the required hardware to accomplish velocity sensing in most of economics keyboards is the use of a rubber membrane, the same used in computer keyboards. I managed to find a complete diode matrix from a roland e35 equipped with 61 keys, with the relative sets of rubber switches which (I suppose) work like a potentiometer due to conductive properties of the rubber. Is it useable to achieve velocity?

I don't think that the rubber membrane is hard to find: lots of roland keyboards have them equipped in their matrix. Also, 1 octave rubber switch is available here in italy for 12 Euros

When I began to work out my first MB64, I was surprised for the lack of the velocity implementation in MIOS. TK answered me that no code was written because if velocity is what you need, then the best solution in financial terms is to mod a casio and midi merge it through MB. Lately I have found a 8x8 button matrix cannibalized from a casio and I found out about the extraordinary possibilities which are now opened to build a full fledged controller in conjunction with all TK's efforts in developing SM driver. I need several 61 keys controllers, and the high cost/poor midi implementation of commercial ones is incredible. First of all, it is impossible to find master keyboards with split zones (with MB you can assign every key to send the event you desire! So 61 keys means 61 split zones :D). I'd like to know if someone is going to work about velocity implementation, I could lend an hand (not enough experience to work it by myself). Thanks for the attention

I know some more about MB64 now, but.. I could easily use the button configuration in mios (* 0 T) to configure buttons behaviour! Thanks TK

Hey Roger Rabbit I hope I'll find some space on the rear of the board to put a support rail or this is going to be a flop! Thanks

Well, actually I changed my design due to an -ehm- user friendliness problem on my previous one, so I didn't try shielded cables. I had 24 cables without shielding and 2 m long. I don't want to talk about that nightmare :) I'm rather sure that you'll be fine with them; You should need only 5 cables in total if I'm not wrong (Vss and Vdd to connect the 2 pots and the button, the 2 wipers of pots+the button line) and I don't think this will lead to noticeable jitter (at least not for cables longer than 2 m). If this should happen, put 100nF ceramic caps as close as possible to the Vss and Vdd pins of the pots to preserve power integrity. I think you can recycle a midi port too if 5 is the exact number of cables as I tried to guess (putting vss in the central pole), at least the poles are at a greater distance than in a sub D Hope it helped

it is a 64x48 cm board, I wonder if a 4mm thick alluminium sheet of these dimensions will result to be flexible

I'm not skilled in mios programming, do you think it is possible to do something like I explained in this topic http://69.56.171.55/~midibox/forum/index.php?topic=4503.0 ?

Thanks tgp, Well in Italy is harder to find a good blacksmith ;D Anyway, aluminium is VERY flexible, I'm not sure it is the best choice for my project.

Ah one more thing: I'm not familiar with joysticks, but I guess 2 axis Joysticks are equipped with 2 pots

I tried this out, it was not exactly an external joystick controller but basicly my plug and play tool was equipped with 2 potentiometers and 4 buttons. IT IS doable, but be careful as long, unshielded and near cables are the primary source of jitter (random values in output from the pots) and sub D ports (I'm quoting TK :)) aren't the best choice for analog signals. Hope I helped Ganbatte!

Hi everyone, I finished the control unit of my MB 64, now I'm busy working at the pedalboard: Height 48cm and width 64cm. I'll have to drill 48x 28mm holes for pushbuttons and 12x 5mm holes for the remaining pushbuttons. Now I'm stuck in its realization, being this a pedalboard I need some material neither heavy nor flexible (a leg+gravity is stronger than an arm :D). I'll apply sustain wooden structures at the extreme sides of the board as I can't obviously hook them in the middle of the board due to the space occupied by the rear side of the pushbuttons.Since previously I did panels in polycarbonate, I'm not very familiar with stronger materials.. I was thinking of a thick anodized aluminium sheet or is there a better material which is convenient in price/weight/strength? thanks in advance Ganbatte!

Hi I connected my MB64 to my PC to evaluate buttons behaviour. I mapped a button to the EQ in Ableton Live to change the filter type. In the CC list of Ableton integrated effects LP is from 0 to ca. 43 HP from 44 to 86 and BP from 87 to 127 (I don't remember the exact values). Is there a way to configure the buttons to send on each press a CC value (1st time 0 2nd time 47 3rd time 127)?

Double posting :D oops I mean can I connect batteries (obviously taking care of the polarity) directly to the 330 cap or it's better if I connect them to 2 output pins of rectifier?

yeah you're right, AAs get low to 1,2V. So I should connect batteries directly to 2200mF cap to bypass the rectifier (I do not want to desolder the rectifier since the core is in place in the case) right?

Thanks Moebius So you suggest to leave out the diode rectifier.. With 6 AAs cells it is not giving problems, I haven't tested what happens when battery discharges (hey 5 hours running and still it doesn't want to stop!) Which kind of problems could I experience with the rectifier installed when the battery discharge? Why it is better to leave out the rectifier? It improves stability of voltage as the batteries wear out?

I would like to suggest also www.kpsec.freeuk.com as introduction

Does anyone has schematics for a dual power supply (I have a 3 state switch and I would like to have both battery supply power and DC 9v transformer supply). Since Core has 2 power pins I have some problems in its realization ??? Could you help me?

Hi midiman Triple check the wirings, I connected in a wrong manner the pots and I experienced the same problem, if the wirings are ok you should check the infos on ucapps which are very precious, I know it is a little hard to understand them if your english is not good, but if it weren't for the troubleshooting guides I would be buying expensive midi controllers now :D

I thought about using an lm family regulator, but finally I found space in my case and I added 2 more AAs :D Thanks anyway!