Mining the Yamaha DJX II

Update: Follow this link to download a free collection of PSR/Tyros DJX-II styles.

Time to party like it’s 1999!

The Yamaha DJX II was the second generation of Yamaha “DJ” keyboards that were targeted for musicians/producers working in “dance” styles (e.g., tekno, hip-hop, drum’n’bass, etc.) Thus, the DJX II uses loop-like “patterns” as its basic musical element instead of arranger styles. The DJX II is best remembered for its unusual keyboard; Some octaves had white whole note keys while other octaves used grey. That’s because different octaves controlled different functions like selecting a pattern to play or transposing a pattern.

The DJX II had a selection of fairly decent patterns in different dance-oriented genres. Although I’ve never heard a DJX, it’s sound was probably hobbled a little bit by the sound set. The DJX II had only 4MBytes of wave ROM! The internal and external patterns are available for download from the Yamaha support site. Seems like a place to find and mine some useable musical phrases, and naturally, I’m looking for the funk. The target keyboard is the PSR-S950 arranger workstation.

The ZIP files from Yamaha unpack into a bunch of standard MIDI files (SMF). Each SMF contains a group of ten, musically related patterns that form a construction set. The SMF has a small amount of set up information at the beginning: General MIDI reset, reverb type select and chorus type select messages. Each pattern within the SMF begins with a MIDI text marker from “1” to “10”. In order to convert the SMF for the PSR-S950, I changed these markers to arranger style markers (e.g., “Main A,” “Intro A,” etc.) and added “SFF1” and “SInt” markers to the first measure. The new marker name determines the method by which the arranger will play the pattern. More about this in a second.

As I mentioned above, the DJX patterns are assigned to keys such that a single key press plays a particular pattern. The patterns are laid out according to black and white keys as follows:

Pattern  Type  Key color
-------  ----  ---------
1        Main  White
2        Fill  Black
3        Main  White
4        Fill  Black
5        Main  White
6        Main  White
7        Fill  Black
8        Main  White
9        Fill  Black
10       Main  White

Main patterns are on the white keys and fill patterns are on the black keys. Fill patterns are not restricted to one measure; a pattern may be anywhere from 1 to 256 measures in length.

Given these considerations, you may need to be a bit creative when assigning a pattern to an arranger section. Please recall that arranger introduction, ending and main sections may be 1 to 256 measures in length. Fill-in and break sections are limited to one measure. A DJX “fill” pattern may be greater than one measure and cannot always be assigned to an arrange fill-in section. Further, you may not even want to assign the fill pattern this way, preferring to invoke the pattern from one of the section buttons instead. The three introduction buttons (sections) are good destinations for a “fill” pattern because the section acts like a manually controlled fill button. The arranger will play the fill pattern (introduction) and then automatically proceed to the selected main section.

Patterns assigned to arranger ending sections are a little problematic. An arranger ending will stop playback unless another section is selected. You’ll need to fast finger the arranger buttons when jamming.

Even though this seems complicated, it’s not really. The more difficult and time-consuming part is dealing with the drum sets and note mappings.

First, some background is needed. The DJX channel layout is very different than the arranger channel layout. Here is the layout for the 53_Soul pattern file, which is typical of all DJX II SMFs:

Channel  DJX PC#     DJX voice         S950 voice/kit
-------  ----------  ------------      --------------
9        126   0  3  BD Kit        --> Real Drums
10       126   0  4  SD Kit        --> Real Drums
11       126   0  1  B900 Kit      --> Hip Hop Kit
12       127   0  5  Analog Kit1   --> Analog Kit
13       0   112 34  Pick Bass     --> Pick Bass
14       0     0  1  Bright Piano  --> Bright Piano
15       0   112 17  Jazz Organ    --> Organ
16       0   113 27  60's Clean    --> Tremolo Guitar

Channels 9 to 12 are rhythm, channel 13 is bass, and channels 14 to 16 are phrases. By (un)convention, channel 9 is bass drum, channel 10 is snare drum, channel 11 is high hat and channel 12 is percussion. Channels 9 to 12 must be set up as drum parts:

F0 43 10 4C 08 08 07 01 F7
F0 43 10 4C 08 09 07 01 F7
F0 43 10 4C 08 0A 07 01 F7
F0 43 10 4C 08 0B 07 01 F7

These System Exclusive (SysEx) messages must be added to the initialization part of the SMF in order to select different drum kits independently under XG.

You’ll need to choose new drum kits for the rhythm channels since the DJX II has its own unique, non-standard kits. This part is totally creative. Who’s to say what the new style should sound like? If it moves your booty, then it’s a winner! Fortunately, the bass drum, snare drum and hi-hat channels seem to use these drum instruments exclusively. This narrows the re-mapping problem. I remapped the kick first just to get a listenable groove going and then tackled the snare followed by the hi-hat. The following chart lists the DJX II drum kits and the roughly equivalent S950 drum kit.

DJX II drum kit           S950 drum kit
------------------------  ------------------------
127 0  5 Analog Kit1      127 0  25 AnalogKit
                          126 0   8 AnalogSet     [GM]
127 0  8 Analog Kit2      127 0  58 AnalogT8Kit   [Major update]
127 0 10 Analog Kit3      127 0  59 AnalogT9Kit   [Major update]
127 0 13 Analog Kit1D     127 0  58 AnalogT8Kit   [Distorted version]
127 0 14 Analog Kit2D     127 0  59 AnalogT9Kit   [Distorted version]
127 0 12 RhBox Kit
127 0  9 Hard Kit
127 0 11 Break Kit        127 0  57 BreakKit
127 0  6 Dance Kit        127 0  27 DanceKit      [Major update]
127 0  4 Electronic Kit1  127 0  24 ElectroKit
                          126 0   3 ElectronicSet [GM]

126 0  0 Electronic Kit2
126 0  1 B900 Kit
126 0  2 DJX Kit                  HipHopKit?
126 0  3 BD Kit
126 0  4 SD Kit
126 0  5 HH Kit
126 0  6 Human Kit        
126 0  7 Scratch Kit

127 0  0 Standard Kit1    127 0  0 Standard Kit1  [Legacy]
127 0  1 Standard Kit2    127 0  1 Standard Kit2  [Legacy]
127 0  2 Room Kit         127 0  8 RoomKit
                          126 0  1 RoomSet        [GM]
127 0  3 Rock Kit         127 0 16 RockKit        [Legacy]
127 0  3 Rock Kit         127 0 90 RockKit2
127 0  7 Jazz Kit         127 0 32 JazzKit
                          126 0 35 JazzSet        [GM]

The DJX-specific kits (BD kit, SD kit, B900 kit, etc.) do not remotely follow General MIDI-ish conventions. It takes a lot of note mapping to get these drum patterns to play sensibly. I recommend playing back the SMF from a DAW (like Sonar) while tweaking the SMF. Do not attempt note remapping on the arranger — you’ll only drive yourself crazy!

Chord progressions are part of the patterns, so the melody/chord phrases need to be transposed like introductions and endings. Please review Note Transposition Rules (NTR) and Note Transposition Tables (NTT) before forging ahead. Since the channel layout is unconventional, the CASM information must be changed to be consistent with the MIDI channel data. Channels 9 to 12 are configured for rhythm NTT/NTR (root fixed, bypass) and the Channels 13 to 16 are configured for intro/ending NTT/NTR (root transpose, bypass). The chord root must be changed to match the phrases (53_Soul: Fm7, 59_ClubFunk: Dm7). You’ll need to identify the root (the musical key) either by ear or by analyzing the chord harmony.

Tool-wise, I did most of the editing in Sonar X3. I used Jørgen Sørensen’s CASM editor ( http://www.jososoft.dk/yamaha ) to create the CASM section for the style and to change the NTR, NTT and chord root information. Special thanks go to Jørgen for creating such great and helpful tools!

Oh, yeah, the final results. Here is a link to the ZIP file containing the 53_Soul and 59_ClubFunk styles. Enjoy!