Doepfer

It's interesting that a lot of people are excitedly posting about the  
Kenton converter without too much thought as to what it's going to do  
and not going to do, at least based on the webpage.

Who knows, maybe I'm missing something myself but I do have some  
thoughts.

Firstly it has a USB B type connector on it meaning at least to me  
that it's meant to connect to a computer. Perhaps it only connects to  
a computer.

Someone mentioned trying to connect a USB keyboard controller. That's  
a really good question I think Kenton neglected so far as far as I  
can read. If you think about it, a USB B to USB B cable to connect to  
a common controller keyboard with USB is going to be hard to find.  
I've only seen those as part of these kind of rare cable connector  
kits where you can swap USB connectors to make all sorts of odd  
combinations, but I don't think that's the problem. The real problem  
is most USB keyboards require a driver on the computer. How is one  
going to install a driver on the Kenton even if you have the B to B  
cable sorted out? Also, I don't know if the Kenton will supply power  
over USB for the keyboard.

As someone posted already, it's worth noting that in the last few  
years a lot of companies started making ultra compact USB to MIDI  
converters small enough to fit inside cables. So I mean if you can  
carry a USB cable to your gig it's only a slight step more complex to  
take an active USB to MIDI cable. The only down side over a regular  
USB cable is you can't ask a friend or run to the computer shop in an  
emergency if you leave it home. I noticed that presumably since Emu  
(owned by consumer computer sound giant Creative Labs) has made cheap  
compact ones the Chinese are now in the copycat business. I don't  
know how high the spec is but I've seen plug and play Chinese USB to  
MIDI cables for under $10.

That brings up the spec. The Kenton device is clearly a MIDI (over  
USB) to CV converter.   They are saying "High specification" and that  
is something well worth seeing test reports about. But it's still  
MIDI meaning MIDI resolution. You are connecting with a USB cable but  
the protocol is MIDI.

I was thinking myself. I guess the dream everyone has is to get  
computer (or controller device) to voltage control system that is  
better than MIDI to CV converters deliver. The big stumbling block on  
the computer is, as I see it is compatibility with all the software  
everyone wants to use. I guess regarding controllers, look at the  
Haaken Continuum's example. They did a custom system that happens to  
use a MIDI cable but switches to a proprietary communications systems  
for their CV out box. It's simply not using MIDI and can deliver high  
resolution. The catch is on a computer everyone wants to use their  
existing software so a huge hurdle is how does it talk to the  
hardware if not by MIDI.

Volta was clever in that they noticed some (mostly MOTU) audio  
interfaces can output DC. So it's a brilliant if not entirely unknown  
repurposing idea. Their value added is clearly that the plugin does  
housekeeping to make an unintended and somewhat unwieldy concept work  
and integrate quite a bit better. I guess there is the whole PC  
issue, not a problem for me, which I'd guess will be solved sooner or  
later. (people like to say VST, but of course there are Mac VSTs that  
won't run on a PC if you made them). I would think MOTU would do well  
with a next generation audio interface with optimization for CV.  
Everyone is talking about a dedicated device just for cv but it  
doesn't sound like something that would sell enough to be priced low.  
I'd think an feature filled audio interface with optimized CV would  
be a safe risk, then again I'm not in their business.

The problem as I see it  for a non MIDI, non audio interface approach  
is you just can't (to my knowledge) get existing software talking to  
brand new hardware classes until you get developers to add it as a  
feature, and if they would it's still going to take several seasons  
to see it happen.  Hence why the audio interface that generates CV  
concept is a sound one ;-)

So as far as I know you can:

convert from MIDI like the last 25 years

use an audio card with DC output + a plugin to generate the desired  
voltage

build a new hardware device that the computer sees as an audio  
interface but is optimized for DC - this one seems promising but  
perhaps a lot of money.

use OSC and build an OSC to CV device, which holds promise except  
only a couple software packages support OSC at this time. The  
advantage of OSC rather than MIDI is OSC has much greater parameter  
resolution... that is if your software can output it.

use a direct custom USB  to CV device, which everyone seems to want,  
but they don't realize is it's a new class and they'll need to get  
software developers to add to their software before it runs. AFAIK  
you can't just make a plugin or a universal driver for a new  
protocol, how would existing software talk to it.

the Buchla approach of using MIDI input then add a proprietary data  
bus between modules for extended capabilities

Anyway those are my thoughts, and I think I should spend more time  
working with Volta rather than writing this long post ☺

nick