Disklavier

In the late 1980s, MIDIMAN made a little Walkman-sized box that
translated MIDI signals to and from a modulated analog audio signal that
could be recorded to cassette tape.  The idea was to provide musicians
with a way to stream MIDI accompaniment at their gigs without having to
drag a bulky computer along.  (Remember, this was long before the age of
laptops, netbooks, iPods etc.)

This was MIDIMAN's original product and their namesake (Walkman ->
MIDIMAN, get it?) but the technology isn't very desirable by today's
standards, as it supported only about 1/8th the bandwidth of wireline
MIDI, and to achieve even that, the MIDIMAN supported only 15 MIDI
velocity levels, filtered out various MIDI events completely (such as
aftertouch), and rearranged MIDI events in the stream to minimize the
temporal inaccuracy of drum channel events.

QRS Music later licensed (or acquired?) this technology from MIDIMAN and
still uses it today for their Pianomation CDs.  In fact, you can decode
QRS CDs using the original MIDIMAN product.  For a while, QRS sold their
own rebadged version of the MIDIMAN box, calling it the AMI (Analog MIDI
Interface).  The limitation of only 15 expression levels still applies
to this day.

This technology is fairly crude, and in regards to note timing and
expression accuracy, it's a big step backwards from playing MIDI files
directly from the control unit or even via wireline MIDI.  It would not
make good use of a Disklavier's capabilities.  Yamaha's own CD format is
considerably more sophisticated.  There is no reason to use a
MIDIMAN/AMI box with a Disklavier since the Disklavier already has the
built-in ability to decode this format.

Note that PianoDisc, QRS and Yamaha each have their own "analog MIDI"
formats that are completely different, though some of these player
systems have been engineered with the ability to play each other's
material.

Mark Fontana


On Thu, 2011-01-06 at 19:31 -0700, ROBERT LEBLANC wrote:

> While I'm familiar with the concept, I've previously never paid too
> much attention to the 'MIDI to Analog-MIDI' topic.
>  
> I'm intrigued with this thread and I'm wondering if anyone can provide
> the MIDIMAN (now owned by M-Audo) product model / name for the MIDI to
> Analog-MIDI interface that's being discussed here.
>  
> Regards . . . / Robert