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How to use midi to Play Wurlitzer Band Organ Music Rolls

Compiled by: David Back June/July 2012.
Amended and Updated August 2012.
Rearranged and updated October and November 2013.

This Document has been compiled to review the musical capability of midi for the purpose of producing music from scanned Wurlitzer paper rolls which sounds similar to a real Wurlitzer organ.

It is assumed herein that you have a knowledge of music, midi and a good midi editor, such as Cakewalk. For basic source of music you can download a good selection of playable wurlitzer midi files from the internet or if you are slightly more ambitious use rolls from my e-roll archive.

Playing Wurlitzer 125 Style Rolls

Organ Style 125

Choosing the correct instruments from the midi repertoire is not simple.
This lineup covers all the necessary midi variables and results in a playable midi file which makes a reasonable simulation of a 125 style Wurlitzer Band Organ when played with General Midi (GM bank 0) patches.

DivisionRank NameMidi
BassStopped Flute1Flute7375100Center
BassOpen String2Cello4275100Center
AccompanimentStopped Flute3Flute7375100Center
AccompanimentOpen String4Cello4275100Center
MelodyStopped Flute5Flute7375100Center
MelodyOpen String6Violin4075100Center
MelodyWood Flageolet7Recorder7475100Center
MelodyBrass Piccolo8Piccolo7275100Center
TrumpetBrass Trumpet9Trumpet5675120Center
PercussionBass Drum10Bass DrumB2 or C37550Center
PercussionSnare Drum10Snare DrumD37550Center

In order to produce a more accurate simulation it may be necessary to play the file using a soundfont which has been produced from real Wurlitzer organ samples.

However having experimented a bit with sound fonts I have found that Cakewalk and the sound cards available to me do not work together. The best sound card and its software can handle sound fonts but Cakewalk is frustratingly reluctant to work with it. I have trawled the Cakewalk website looking for details of which Cakewalk versions support which sound cards. I did not find anything useful. Thus, knowing that the Brass Trumpet sound was what I needed I auditioned the entire General Midi bank 0 to find the most convincing Brass Trumpet sound. The tenor sax won the competition.

While working on this scheme I found that Cakewalk happily accepts and appears to use the midi velocity input but does not save the information when the file is saved. This may be because it is arguable that velocity is not relevent to any of the instruments used. In fact I found, much later, that Cakewalk DOES save midi velocity for every individual note of every instrument. Velocities translate to volume and can be viewed in "List View".

Finally I have tried to automate this process using the Cakewalk CAL language but have found that in my version (which is quite old) it was incapable of doing anything useful.

Playing Wurlitzer 150 Style Rolls

Organ Style 153 (October 2013)

The 153 organ has a lot more pipes plus automatically operated stops, shutters and bells. This makes it more challenging to simulate than the much simpler organs above. The benefit is that there is more variety in the music which makes it more interesting.

In order that you can realistically instrument a style 153 organ you must first calibrate your computer's sound card using a midi patch which makes a continuous sound e.g. any organ like instrument.
The figures for mine are below, you can use this as a guide but yours will probably be different.

Midi Velocitydb
Note: -6db = 1/2 voltage = 1/4 power.

It is easiest to add the cymbal into the percussion channel before converting the midi file from type 0 to type 1.

Since there are two sets of violin pipes for both accompaniment and melody each set needs to be set to +3db, corresponding to 2 X power.

You will need to decide how much sound attenuation there is when the shutter is closed. In my case I have used 6db. In a real organ there will be high frequency attenuation as well but midi cannot cope with this so I have ignored it. However it could be introduced later by editing the .wav file.

I have made sure that the instruments I have chosen for each channel are working within their normal musical range.

Since this simulation uses all 16 midi channels I also tried to check the amount of headroom there was within the system. However even with all channels playing at a high level I was unable to reach a convincing limit. With a digital sound system it is not all that important to make full use of the headroom so I erred on the side of safety and used a velocity of 65 as my base level.

Dont forget to transpose the indicated +8va and +16va channels and for perfection transpose all except control and percussion down 2 semitones.

All midi data except that shown in the table below uses the normal midi default values. When the stops are closed the notes do not play so I simply deleted the appropriate notes.

DivisionRank NameMidi
TromboneWood Trombone1Tuba586540
Bass8' Stopped Diapason2Contra Bass436540
Bass +8va4' Open Diapason3Bassoon706540
Bass +16va2' Stopped Diapason4Flute736540
Accomp.Stopped Flute5Bassoon706540
MelodyStopped Flute8Flute736540
Melody +8vaOctave Violin *9Calliope826540
MelodyOpen Flute *12Pan Flute756540
MelodyBells B13Celeste8100100+7db
TrumpetStopped Pipes *14Oboe686540
TrumpetCello *15English Horn696540
PercussionBass Drum10Bass Drum6565B2
PercussionSnare Drum10Snare Drum6565D3
ControlCoin Trip6Piano55E2
ControlAll Off6Piano55Eb2
ControlStops Open *6Piano55D2
ControlBells on B6Piano55Db2
ControlShutter Open6Piano55C2
* = Stops, Automatic stop
B = Bells, Automatic stop

The easiest way to edit the controls is to add descriptive markers at all the points where the controls change, it is then easy to select the data between these points and edit all the appropriate channels in one go.

Some of the tunes on some rolls begin without having set up any controls. Having observed several 153's in action and seen the shutters snap shut at the end of each tune I am pretty certain that the "Coin Trip" also turns all controls off. So where there are no controls set up at the beginning of a tune assume that controls are "all off".

The best way I have found so far to convert midi files to .wav files is to record the wav file whilst playing the midi file in real time. I have looped "line out" back to "line in" with a T junction to connect my amplifier and speakers.