[LAU] Control surfaces - whats already available

Len Ovens len at ovenwerks.net
Sat Jul 5 20:56:34 UTC 2014


On Sat, 5 Jul 2014, Fons Adriaensen wrote:

> On Sat, Jul 05, 2014 at 10:17:21AM -0700, Len Ovens wrote:
>
>> I do want to try the rotary encoder though. either with a large
>> wheel (actually 2-3inch is not that big) or belt with no LED strip.
>> The on screen fader position should be good enough.
>
> In case you'd consider the motorised fader, there's an Arduino
> project using it:
>
> http://blog.codyhazelwood.me/motorized-faders-and-the-arduino/

That was one of the projects I looked at. Thank you.

> There's one problem with this: the author has the H-bridge
> 'enable' pin hardwired. This means that the motor always
> sees a low-impedance voltage source. The voltage can be
> zero, but that will make the motor resist movement.

Good to know... Yes that makes sense, right away. From the look of the 
video it does not add very much resistance, but a quick fader movement may 
be hard on the motor still.

For me it is a toss up between using motorized faders and just supplying 
enough faders (24?) that don't need a motor. The simple answer is that 
while I don't use more than two inputs at a time, even a relatively 
simple project could use up all my faders by the time I have a few subs 
and master. 8 motor faders starts to look cost effective pretty quick. The 
ability to come back to a project and have my faders where I left them 
without a cue sheet (which would only be aproximate anyway) would be a 
bonus that is hard to put a price on.

My first project will not have (resitive) faders because the interface 
does not support analog inputs. It will have buttons and maybe I can work 
encoders in there too. It is based on a PC USB keyboard ($3 new) which is 
not MIDI out of course, so the SW interface will be in the computer based 
on the code from actkbd. I do not know if I will be able to get encoders 
to work past the debounce, but even having transport control and other 
button based controls will be worth something.

It may even be worth while to be able to use the numeric pad for midi out 
while letting the rest of the keys go through as normal.

--
Len Ovens
www.ovenwerks.net



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