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