flexbex Posted January 12, 2012 Report Share Posted January 12, 2012 (edited) Hi there i hope the question wasn't answered too often I am looking for an endless Potentiometer. in the moment i am using a rotary encoder with 24 steps which is quite nice. But the problem is that instead of a "normal potentiometer" I have too turn nearly 6 times to change the midi value from 0 - 127. Of course I could use an acceleration as mentioned in the Faq's but this is not exactly what i want cause it gives u no exact controll when u turn it. So I got a hint that they use in the APC40 sth. like an endless potentiometer. I googled a bit but didn't find the right part. Is there somebody who could help me. cheers Flex Edited January 12, 2012 by flexbex Quote Link to comment Share on other sites More sharing options...
sidmonster Posted January 12, 2012 Report Share Posted January 12, 2012 Hi there i hope the question wasn't answered too often I am looking for an endless Potentiometer. in the moment i am using a rotary encoder with 24 steps which is quite nice. But the problem is that instead of a "normal potentiometer" I have too turn nearly 6 times to change the midi value from 0 - 127. Of course I could use an acceleration as mentioned in the Faq's but this is not exactly what i want cause it gives u no exact controll when u turn it. So I got a hint that they use in the APC40 sth. like an endless potentiometer. I googled a bit but didn't find the right part. Is there somebody who could help me. cheers Flex apc uses encoders, no such thing as an endless potentiometer. You can set the MB64 to use encoders in fast mode which will create the behavior you're looking for Quote Link to comment Share on other sites More sharing options...
flexbex Posted January 12, 2012 Author Report Share Posted January 12, 2012 Thx for the fast reply but when i get it right with the fast mode it works like this: the faster I turn the Encoder the more steps are skipped like a mouse on the computer would do. But this wouldn't be a solution for me cause I want a predictable position after I turned the shaft. This is why I was thinking of a 360 degree(or nearly 360) potentiometer. Because with this one I would have the advantage of both the soft take over ability from an encoder and the fast response of a potentiometer. hope I could express my concerns right. thx Flex Quote Link to comment Share on other sites More sharing options...
Hawkeye Posted January 13, 2012 Report Share Posted January 13, 2012 (edited) Hi there, a good choice imho is the "press to accelerate" function originally brought to us by the elektron mds - gives a very controllable behaviour - very high-res when not pressed (feels better than a potentiometer), and quick parameter changes when pressed. The MBSEQV4 supports this since a while, and you can implement this behaviour for yourself in another MIDIbox project. Highly recommended. If you combine that feature with a LED ring, you have the ultimate user interface element :-). Best regards! Peter Edited January 13, 2012 by Hawkeye Quote Link to comment Share on other sites More sharing options...
flexbex Posted January 13, 2012 Author Report Share Posted January 13, 2012 Hey @Hawkeye you could read my mind I just came back to this forum with the same Idea with the pushbutton function. And the Led ring was my plan allready before I came here. ;) Another Idea I tried yesterday was to read out not every pulse from the Encoder but to read out every change of A and B which gives a 4 times higher resolution. I was affraid to get a lot of Noise/bouncing errors especially cause I didn't used capacitors and it's a detent type of encoder(which I supose to bounce more). But suprisingly it worked pretty fine and just had 2 or 3 errors per 360 degree rotation. I now orderd an EC12E from Alps and some Encoders with a button from Bourns to try this out. And get a feeling of how they react. @Hawkey sorry I am not firm with the different Midibox projects cause i develope all on my own on a MSP430 so I can just participate in the the Hardware section One question i don't have a modern Midi controller at home but how is it on sth like the Akai Apc40 or sth equal when I turn an encoder it looks like on videos I watched that it is just a 270 degree(+/- it was hard to see everything) angle between fully opened and zero. Because with my method I mentioned above I still need 480 degree to change a value from 0 to 127 when I have a 24 pulse per Rotation Encoder (128/4=32 pulses 360/24=15degree ->32*15=480) cheers Flex Quote Link to comment Share on other sites More sharing options...
Hawkeye Posted January 13, 2012 Report Share Posted January 13, 2012 Hi Flex, lets say you configure/develop it like this: pushed state = fixed 10 units per tick = parameter 0-127 in 13 ticks or 13x15 = 195 degrees reached. unpushed: fixed 1 unit per tick = very hi-res unaccellerated fine tuning possible. both states are without acceleration! That results in a predictable behaviour not depending on rotation speed and current moon phase :-) Dunno how AKAI does it, but they either have higher-resolution encoders (don´t know what is available?) or they use accelleration, or they don´t allow real finetuning (e.g. minimum change of 2 units per tick). I also got the pushable alps stec12e encoders in the midibox seq v4 and they work really nice! Greets, Peter Quote Link to comment Share on other sites More sharing options...
lylehaze Posted January 14, 2012 Report Share Posted January 14, 2012 I just checked on DigiKey for rotary optical encoders.. They offer anything from 8 to 2048 pulses per revolution.Opticals are a bit more expensive but might last forever. I think I paid about $20 for the one I'm using here. Have fun,LyleHaze Quote Link to comment Share on other sites More sharing options...
flexbex Posted January 14, 2012 Author Report Share Posted January 14, 2012 I just checked on DigiKey for rotary optical encoders.. They offer anything from 8 to 2048 pulses per revolution.Opticals are a bit more expensive but might last forever. I think I paid about $20 for the one I'm using here. Have fun,LyleHaze Yes I know but as soon as they are above 24 pulses they will cost more then 12 Euro and this is too much for me cause I want to use at least 16 Encoders. Quote Link to comment Share on other sites More sharing options...
J. C. Aqfaq Posted January 31, 2012 Report Share Posted January 31, 2012 So I got a hint that they use in the APC40 sth. like an endless potentiometer. I googled a bit but didn't find the right part. Is there somebody who could help me. Not sure about the APC40, but Alesis Ion and Micron have these, as well as Akai Miniak (rebranded Micron). The feel is very nice for fine tweaking. I have been looking after these for a while: www.instrumentalparts.com in the US ships replacements wordwide, but it's not too cheap (part no. 0-09-0044 for Micron, 0-09-0036 for Ion). If you google around with the part numbers, you might come up with other stores as well (there is www.disco-store.at in Austria, but they don't ship abroad). Some Numark devices might have these as well, but I'm not sure... To read those endless pots you need two ADC-channels/pot and use some logic to eliminate values within each channels electrically inactive zone. A15-3P from Piher might also work, but I don't know where to get one. Anyway, I am going to do some experiments with "endless pots" and MIDIbox as soon as I get my hands on some. Will let you know. If anybody knows where to get for example #0-09-0044 cheaply (or happen to live in Austria, willing to trade with me...), or has prior experience with these, I'm eager to hear. Quote Link to comment Share on other sites More sharing options...
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