[Ardour-Dev] OSC next

Len Ovens len at ovenwerks.net
Fri May 13 11:53:59 PDT 2016

On Fri, 13 May 2016, Melanie Bernkopf wrote:

> yes I can only give a full ack to this it is just mimic of the position and not
> about gain or DB.

Yes and no. With either gain or dB I can remotely say I want x amount of 
gain. It is easy to put a button in that zeros a fader with either dB 
(send 0) or gain (send 1.0). It is impossible to do that with 1023 INT. 
800 comes closest at 0.006990539841353893 dB. (Using two surfaces one with 
int1024 and the other with dB, setting position to 799, 800 or 801 and 
seeing what Ardour sends to the other surface) So with dB, I can on the 
surface enter as text an exact gain in dB. Also, the text value on the 
surface shows the value in dB which is much more useful to the user than 
some number from 0 to 1023.

For a comparison of int1024 and dB in real use.
[1] see below for more info on what I am using

> Through my research about controllers for osc i found that there is mainly
> software like touch osc used real hardware controllers are still very rare. Maybe
> because Micro controllers have a hard time with floats and hardware producers
> actually don´t use something different than what is for example used on the
> Arduino.

The real problem with OSC is standards (actually a lack of standards). A 
manufacture cannot make a HW surface with any expectation that it will 
work with all DAWs. (OCA may change this) As such, HW manufactures just 
stick with MCP (and throw in HUI just for PT who are stuck in the dark 
ages) which all DAWs including Ardour, can handle. So HW OSC controllers 
are pretty much all DIY or require some sort of middleware (the X32 has 
OSC out but it is so convoluted as to require middleware to work with 
anything other than other x32 bits. I don't think it is even compatable 
with the X-air mixers).

The other standard people use (not Ardour) is EuCon. This is closed... 
actually MCP is as well, but the original LC manual (chapter 13) 
documented the LC protocol and MCP is basically the same except for 
surface detection which doesn't _have_ to be used. (call it openish) EuCon 
is a middleware blob library that paying users/developers can interface 
with. It is interesting to note that most of the EuCon surfaces do have 
MCP as a backup so you can use their surface with whatever DAW.

EuCon is very similar to OCA and has a similar c++ interface.

> So it is mainly on one side Micro controllers that give people the feel of
> working with a Mixing console having trouble with floats and on the other side we
> have software that can handle floats without problems.

Considering the cost of a set of at least 8 motorfaders... adding a RPi in 
the middle to handle floats and conversions... and to make an OSC 
controller more intelligent and more useful than a MIDI controller just 
makes sense (there are lots of other boards like the RPi, just using one 
everyone knows about).

> VUmeter is something different that really uses gainDB but if I get it right it
> is not about Meterbridges right now so let us leave that out now.

Vumeter is best in dB yes... In my surface the meter follows the fader in 
dB with the same break points. This means the numbers on the fader also 
act as a scale for the meter (yes there is a meter in there between the 
fader and the buttons)

> As said before int1024 seems to be the most versatile.

Well, lowest common denomiator anyway.

Len Ovens

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