[ David wrote in 210117 MMDigest:

> I am seeking information on the availability of a MIDI synthesizer
> that I can program to replicate the sound of my organ to enable me
> to test run MIDI files in my studio before playing them on the organ. 

Hello Wallace, Thank you for your reply to my MMD request. I have
attached a MIDI map for my organ which I have built fully chromatic
over the Carl Frei range to give me more flexibility in the choice of
music sources. However, for now I am playing only a true Carl Frei
72-key scale and sourcing MIDI files from a professional arranger
in Holland.

Eventually, I'd like to try my hand at arranging my own music, hence
the desire for a synthesizer. Note that my MIDI map uses standard
scientific pitch notation where Middle C is C4 MIDI no. 60. I am aware
this notation varies in some parts of the world.

I am using only one MIDI channel throughout the range as I have a
single MIDI decoder for each section (Bass, Melody, etc.) feeding all
of the registers in that section.

It appears my biggest challenge in setting up a synthesizer is dealing
with the tone changes caused by register switching. When designing the
organ, I decided to install a pallet magnet under every pipe in the
organ, which makes register switching quite simple. I have a dedicated
MIDI decoder feeding the register commands to a microprocessor and
look-up table which switches the common lines for each register through
a simple relay system.

Then of course the next challenge, as you mention, is imitating some of
the unique sounds of the organ such as Bourdon Celeste and Undamaris.
I have just started learning about sound font files and the like.

I have already encountered some of the percussion issues you mention.
My bass drum is uses a traditional pneumatic bellows which is catered
for by the lead [time advance] being built into the MIDI message.
However, my snare drum is solenoid operated, so I had to build in an
artificial delay into each stick to neutralise the MIDI lead. As I am
playing primarily European music files (books) having one hole for each
stick, I chose a non-reiterating snare drum.

I have studied MIDI File Mapper earlier from some of your previous MMD
posts. I can see such a utility would be ideal when converting other
music scales and MIDI music in general to play on my organ. I assume
the audio format is the starting point before converting to the Ames
AMI Sys 7 format, and converting in the other direction would encounter
insufficient information. I can hear the difference between these
formats.

From the various replies to my post, it appears there is no software
or hardware product that could be customized to meet my initial
requirement; that is, to simulate the sound of the organ without
further modification of the MIDI file. It seems I am faced with
building an "electronic organ" with the same registers/tones as my
physical instrument.

Regards,
David Dilks
Waikanae, New Zealand

 [ My MIDI layout1.xlsx
 [ https://www.mmdigest.com/Attachments/21/01/26/210126_030454_My%20MIDI%20layout1.xlsx 

 [ MIDI File Mapper by Mark Heath is archived at
 [ https://github.com/markheath/midifilemapper 
 [ See also the author's blog at
 [ https://markheath.net/post/new-version-of-midi-file-mapper 
 [ -- Robbie