Axcore Experimental Synthesizer

#21

sorry for the barrage of questions... just intrigued how this all fits together....

a small clarification:

so my assumption is you mean, that the USB is for midi output only, so your using the DIN, so that you can 'chain' the boards together. then presumably you could connect this to the axoloti either via midi din or to the usb host port.
e.g.
usb64 (1) -> midi din -> usb64(2) -> midi din/usb host -> axoloti.

not too important, to be honest (more out of interest) as the data rates are slow anyway... so id probably be best taking into the midi din on the axoloti, and then use the axoloti usb host for my midi controller. (which has much more data traffic)

one thing I'm not clear on, is the USB64 gives no information on what type of pots to use...
there are quite a few to choose from on musicding... I can understand the difference in lin/exp for different uses, but no idea what resistance is needed, or sizing... any suggestions?

sorry, one final question (its the electronics I'm weak on)
for the pots/switches can you connect them to one common +5v / GND coming from the usb64 board...
Im a little confused as to why they provide a +5/GND on each JP1-8... rather than just one that you then use for all pots/switches.
or do I need to group the pots/switches into banks of 8, and then use the +5/GND from the appropriate JP.
(perhaps there is a maximum current on each JP?)

thanks
Mark

#22

Ok sorry my English is not so good to explain. Next try.

If you wanna use both USB64 together, so that you have midi cc from 0 to 127, you need both USB outputs separate with a hub. You can't chain both Via USB. You need the DIN Midi in and outs to chain both together.
All Equipment which goes into DIN Midi in, a sequencer for example, you can't route through the USB Connector. You need the midi out to do this. The USB connector works only with the unit itself.

You can use pots from 4,7k to 100k linear not expo. I prefer 10k pots.
Doepfer grouped the inputs into 8 blocks with there own 0V and +5V for a better overview. Of course you can use only one of the 0V and +5V for all 64 inputs.

But all my controller and also the Axcore Synth are wired in blocks with separate 0V and +5V.

And very important, all inputs of the USB64 must be wired if you need this input or not.

#23

yup, got that from the manual, wire to GND or +5v as appropriate. (i assume GND is for 0 on the CC value, so most appropriate for me)

thanks very much for your answers, really helpful... I think I've got it all clear in my head now.
very tempting, will have a serious think about the best way forward... might order one USB64 and a bunch of 10k pots and some switches, and prototype something.

#24

Yes cool. And after that you think about how to save and restore presets. :relaxed:

#25

It looks fantastic! Is there any chance of trying out the patch of the Axcore?

#26

really great job, do you have any video or audio demo ?

#27

I´m hard working on a Video. Its easier for me to build a Synth than to make a good video. Lol.
But i can place a link to an Audio file here, if anyone want this.

Best

Mario

#28

yes audio file it's cool

#29

It really looks great project
I was wondering, are all your controls going into the axoloti via the Doepfer board ? Does it not limit you to 128 values for each controller (7 bit)?
Since using axoloti's 10 bit (1024 values) gpio's, I have a problem going back to the old midi standard again.

hdi pcbs

#30

Hi, is there any chance of sharing your monophonic patch? :smile:
Great work here!

#31

hell yeah. @SynthProject in the house

#32

http://www.doepfer.de/usb64.htm Is this the doepfer midi OEM you used? I wasnt aware this existed, pretty awesome!

#33

Yes, i use two of them.

#34

I was wondering, are all your controls going into the axoloti via the Doepfer board ? Does it not limit you to 128 values for each controller (7 bit)?

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