Dale Abrams asked about using an iPad as a MIDI file player.  I have
been having some success using an iPad as a controller to drive a
MIDI system installed on a Wurlitzer band organ.  Lack of time has
prevented me from enhancing, improving, and getting the bugs out of it,
so I still presently prefer to drive the MIDI through an SD Card Reader
and controller or a laptop computer running a music jukebox program
such as vanBasco Karaoke Player.  My comments below reflect my
experience on the band organ, but it should have similar application
to any MIDI system.

The iPad (or iPod, as it is essentially the same interface) is
capable of driving a MIDI controller, in my case the very capable
Omega Electronics MTP-8.  The initial problem is that the iPad does
not recognize MIDI files (*.mid) as an acceptable type of file, so
saving and accessing these files is somewhat problematic without
"tricking" the iPad into accepting them.

The software I am using on the iPad is Symphonix Evolution.  Since it
is a MIDI player, once a *.mid file is saved in the iPad, it will load
in Symphonix, which has a reasonably good interface and features to
drive a MIDI file.

Next, you need an interface to connect the iPad to the MIDI Board.
The easiest way to do this is the standard MIDI-to-USB interface cable
available on eBay for about $10.  This cable has a built-in driver that
effectively connects the iPad to the MIDI board.  This cable has a USB
interface on one end and a standard 5-pin MIDI port on the other.  You
also need a converter for the iPad that converts the Apple interface to
USB (called a "camera connection kit" by Apple).

There are also more sophisticated solutions to the connection from iPad
to MIDI Board.  Line 6 products recently introduced a "Midi Mobilizer
II" that adds greater controls to the connection.  IK Multimedia
released a similar product called "IRig Midi".  I have experimented
with all of these and find they all work quite well, with various
quirks and features.

All of these applications have a huge "cool factor".  It's quite
striking to see a Wurlitzer 165 band organ with a non-invasive MIDI
system playing music from an iPad or iPod.  Some may remember a
software product about 15 years ago called "Itty Bitty Midi" that
played MIDI from a Palm Pilot!

My biggest problem that still needs to be resolved is the fact that
all of the above essentially are single tune players: load a tune,
adjust the tempo, play, finish, delete, load another, and repeat the
process.  The SD Card Reader or the laptop computer jukebox driver do
not have these problems.  When time permits, I hope to continue to
work on these.  Meanwhile, I'm sure others have developed some other
solutions!

Glenn Thomas
Princeton, New Jersey
http://www.nickelodeonhouse.net/