Midi Drum Samples

Midi Drum Samples

Scanning and converting a player piano roll into MIDI form is a fairly straight forward process. Imagine a flat-bed computer scanner copying a page, where the image reading head moves along a track. Now picture the scanning head stationary while the paper itself moves, This can also be used for drum samples.

My scanner was loaned out to me for the duration of my project by a good friend, Robert Perry of New Zealand. (It was no small feat getting the scanner back into the United States and shipped to me). As a Mark 3 generation scanner, it is capable of capturing all perforated data on the roll, but not printed material such as song lyrics or leader song identification. The scanner’s components were designed by fellow roll archivists Warren Trachtman, whose web archive has paved the way in the hosting of many thousands of player drum¬†piano rolls. The scanner itself was built by Terry Smythe, another enthusiast, in Canada. I A satisfactory image is created for a good listening experience, and the images resulting from my scans can be used to perforate new re-cut music rolls so that these performances can continue to exist on new rolls.

The main scanner components are:

  • The Roll Frame: This is the red wooden frame that transfers the roll from the upper area to the lower take-up spool (where the roll attaches to on the bottom)
  • CIS Reader: This is the long metal bar in the middle of the picture that receives the image. Light shines through from a lamp behind the roll and the CIS Reader pics up the light variations.
  • The MK3 Circuit Board: This circuit board is mounted on the back wall in the middle and converts the image data that the CIS reader head receives into a .CIS image of the music roll.
  • The transmission: The stepper motor (Power’s the roll’s movement) connects to the transmission to pull the roll onto the lower take-up spool. The stepper motor is powered by a Circuit board to insure precise movements.
  • ¬†Encoder: This wheel (top left of the picture) encodes precise movements so that the image converts to a uniform and steady MIDI file.
  • The scanning process can be summed up into three main points: 1.) Initial setup of the scanner to the computer: 2.) Roll conversion to midi; 3.) Adding song information to the midi and hosting it.

 

Step 1: involved actually downclocking my computer so that it was capable of interacting with the DOS-based scanning hardware and software. The scanner is connected to the computer via a standard LPT-1 Parralel port connection. Once the computer was able to boot into DOS, by executing the program, it asks for general information about the roll, including type of roll(standard 88-note rolls in my case), and the roll tempo. The software creates the image on a virtual drive in DOS and at the end of the scan copies the image to the hard drive.

drum samples
Mixing drum samples in the studio

Step 2: involves booting into Windows and bringing up Warren Trachtman’s RollConverter Software which is able to convert the scanned drumsamples and CIS image of the roll into MIDI format. See the picture to the lower right. Click on it for a larger view showing more detail about the software. There is some adjusting needed to make sure the MIDI created plays correctly and at the right tempo.

Step 3: is a simple custom made editor program that takes the MIDI file without any roll information and adds metadata of your creation inside the file; including song content like Roll Brand, performer, copyright information, roll tempo range, and type of song. Once this refined MIDI file is created, it is a simple matter of adding it to the online archive.

Once The Piano Roll Has Been Scanned, I switch the transmission to re-wind and re-wind the music roll. Care is taken to insure that the edges of the paper are not torn during re-wind. I put the roll in a special area for rolls already scanned to seperate them and to make organization easier.

For more technical information about my variant of drum sample scanner, I suggest you visit Terry Smythe’s Website. If you’re interested in building with drum samples, This document along with Terry’s site will get you started, but I also suggest getting in contact with The International Association of Mechanical Music Preservationists (IAMMP), who are part of a Yahoo group here. They can help you answer almost any question.