Wednesday, November 2, 2011

Roland/Boss RC-50 Loopstation PATCH.RC5 File Analysis

Greetings once again readers, it's been a while..

Tonight I want to talk about the Roland RC-50 Loopstation.  It is a really nice, yet-not-quite-perfect-yet, looping pedalboard that lets one record up to three different tracks on a patch.  It's 24minutes of 16-bit stereo 44.1kHz memory is, in this day and age, a bit paltry, so one has to heavily utilize the USB file-sharing capability of the unit.

(future project:  RC-50 RAM upgrade?)

For now, I just want to easily transfer #1 my files, and #2 certain patch settings, such as tempo, time signature, guide rhythm selection, volumes, etc..  Sadly, Roland/Boss has not offered any kind of host-side patch-editor for the RC-50.  Will they?  I don't know.  The RC-300 is the new baby, and sounds like it has better file-handling capabilities, so we'll see.

Now, for either Loopstation... Since I'm a Cakewalk user, the dream would be to have an RC-50 Cakewalk add-in that would just convert the RC-50 patch values, such as tempo, time-signature, etc. to the appropriate project and channel track settings on Cakewalk   One could offer an interface to instantiate a copy of the RC-50 guide rhythm as a new channel strip.  It could be a GREAT melding of technologies and would really expand the RC-50 as a compositional tool.  And now that Cakewalk is under the Roland roof, maybe we'll see something pop up.   (Hint hint)...

Speaking of that, Roland/Boss, (the legal team in particular), if you're reading this : What I'm doing here is posting my own comparison of the PATCH.RC5 file generated by twiddling knobs and settings on the RC-50...  and then seeing what changes on the PATCH.RC5 file.  These are visual observations whose results, I don't think, violate any kind of applicable license-agreement, NDA, etc.  I am publishing these findings in the hopes of helping proud RC-50 users get more out of their equipment.  I do this in the spirit of goodwill - that more people will feel good about using your products and will recommend them to others.   (I urge you to publish file and interface specifications a bit and let those in your user community contribute to your own product's growth - maybe even saving you some of the heavy-lifting along the way).  So I do humbly ask that you allow me to post my research here without legal hassle.    Thanks.  I hope my work improves your bottom line.  You've make some truly excellent gear over the years, and I don't mind giving back.

Allright on to the good-stuff:  So here's what I've found so far...
(Note: this is an ongoing project, specs will be added as found.  Also, please comment with any corrections or your own findings)

(DISCLAIMER - Blogspot's text handling doesn't work well for this mostly tabular data, but I think it's still readable.  And I've worked on it long enough.  I'll figure out how to better format it or see if there's a code-box feature that's hiding from me. Hope it helps!)

PATCH.RC5 analysis

Notes & todo:
Done:  All options under the NAME/PATCH menu figured out - still a gap at 0x15-0x1c
ToDo:  many patch-level bytes, phrase-level bytes remain

File Summary:

File Header size = 64 bytes
Patch len        = 87 bytes * 100

// NOTE: Byte offsets are from file-zero in this section:
Range (0x = hex)        Patch Offset  Field Name                      Values, notes, etc.
---------------------   ------------  -----------------------------   ------------------------------------
   0 0x00 -> 63 0x4e                  PATCH.RC5 File-level Header     BOSS RC5 FORMAT TYPE 1.00 V1.00 B0171 2006/05/06
  64 0x40 -> 79 0x4f    (0x00-0x0f)   Patch 001: Name                 
  80 0x50               (0x10)        Patch 001: Patch Volume Level   (0 - 100)
  81 0x51               (0x11)        Patch 001: Phrase Change        (0 = IMMEDIATE, 1 = LOOP END)
  82 0x52               (0x12)        Patch 001: Fade Out             (0 - 100)
  83 0x53               (0x13)        Patch 001: Fade In              (0 - 100)
  84 0x54               (0x14)        Patch 001: MIDI Sync            (0 = AUTO, 1 = INTERNAL, 2 = REMOTE)
  93 0x5d -> 0x5e       (0x1d-0x1e)   Patch 001: Tempo                (400 - 2500 (40.0 - 250.0 bpm))
  95 0x5f               (0x1f)        Patch 001: Patch:Input Out      (0 = MAIN, 1 = SUB , 2 = MAIN+SUB)
  97 0x61               (0x21)        Patch 001: Guide Level          (see notes below for values, etc)
  98 0x62               (0x22)        Patch 001: Guide Rhytm          (see notes)
  99 0x63               (0x23)        Patch 001: Time Signature       (see notes)             
 118 0x76               (0x36)        Patch 001: PHRASE1 BLOCK START           
 123 0x7b               (0x3b)        Patch 001: Phrase1 Level        (see notes)
 128 0x80               (0x40)        Patch 001: Phrase1 Simulstart   (0 or 1)
 129 0x81               (0x41)        Patch 001: PHRASE2 BLOCK START           
 134 0x86               (0x46)        Patch 001: Phrase2 Level        (see notes)
 139 0x8b               (0x4b)        Patch 001: Phrase2 Simulstart   (0 or 1)
 140 0x8c               (0x4c)        Patch 001: PHRASE3 BLOCK START          
 145 0x91               (0x51)        Patch 001: Phrase3 Level        (see notes)
 150 0x96               (0x56)        Patch 001: Phrase3 Simulstart   (0 or 1)
 151 0x97 -> 237 0xed                 Patch 002: (full patch)        
  .                                          .
 238 0x98 -> 324 0x144                Patch 003: (full patch)        
  .                                          .
  .                                          .
8590 0x218e -> 8676 0x21e4            Patch 100: (full patch)

// More specific notes about certain patch settings are found here...
// NOTE: Byte offsets are from each patch-start in this section:

Tempo Patch offset       = 29 0x1d (msb), 30 0x1e (lsb)
Tempo value 2-bytes, in tenths of bpm
Tempo value range min 0x0190 400   (40.0 bpm)
Tempo value range max 0x09c4 2500 (250.0 bpm)

Guide level offset       = 33 0x21
Guide level min = 0   0x00  (screen value = 0)
Guide level mid = 50  0x32  (screen value = 100)
Guide level max = 100 0x64  (screen value = 200)

Guide rhythm offset      = 34 0x22
Guide rythm start value  = 0  0x00
Guide rythm max value    = 55 0x37

Time Sig offset          = 35 0x23
Time Sig Values:
00 = 2/4
01 = 3/4
02 = 4/4
03 = 5/4
04 = 6/4
05 = 7/4
06 = 5/8
07 = 6/8
08 = 7/8
09 = 8/8
0a = 9/8
0b = 10/8
0c = 11/8
0d = 12/8
0e = 13/8
0f = 14/8
10 = 15/8

First Phrase1 Level Field= 123 0x7b
First Phrase2 Level Field= 134 0x86
First Phrase3 Level Field= 145 0x91
Phrase level min = 0   0x00  (screen value = 0)
Phrase level mid = 50  0x32  (screen value = 100)
Phrase level max = 100 0x64  (screen value = 200)


Anonymous said...

How did you open the file in the first place - what viewer did you use? Any help would be much appreciated.

Great article by the way. I'm a cakewalk user too and I agree with your suggestions.

slinky said...

Hi there,
I used a hex-editor called "Frhed" to open the file and examine the raw contents. I'm hoping someone may take my start and create a handy "decoder app" that will open the file and display the pertinent information in a more human-readable form.