Alesis QuadraVerb: SysEx Format

Bob Page, February 12, 1989

This information is presented in the hope that it will be useful, but no warrantees about its accuracy are expressed or implied. I'm interested in any changes/additions you have. Feel free to use this information in any way for any purpose, but please don't pretend you wrote it (leave my name in this document). I'd be happy if you send me code you write based on this info, but of course that's up to you.

Alesis is currently saying they are not going to release the QuadraVerb info "at this time". That could mean the "format" is subject to change, or they are withholding the info until some pet software companies get QV patch editors to the market, or maybe some other reason, I dunno. In any event, I needed the info, so I created it. And on with the show...

Contents:

QuadraVerb System Exclusive Data Encoding Format

You first need to understand how the QV encodes its data for MIDI transmission. Although all 8 bits of a byte are used internally, the MIDI specification reserves the highest bit for status messages, so these high bits have to be "removed" from the data stream. The 8-bit QuadraVerb data is encoded for MIDI transmission into 7-bit data. The encoding looks like this:

Seven QuadraVerb bytes (each line represents one byte):

   Byte 0: a7 a6 a5 a4 a3 a2 a1 a0
        1: b7 b6 b5 b4 b3 b2 b1 b0
        2: c7 c6 c5 c4 c3 c2 c1 c0
        3: d7 d6 d5 d4 d3 d2 d1 d0
        4: e7 e6 e5 e4 e3 e2 e1 e0
        5: f7 f6 f5 f4 f3 f2 f1 f0
        6: g7 g6 g5 g4 g3 g2 g1 g0
are transmitted as eight MIDI bytes:
   Byte 0: 00 a7 a6 a5 a4 a3 a2 a1
        1: 00 a0 b7 b6 b5 b4 b3 b2
        2: 00 b1 b0 c7 c6 c5 c4 c3
        3: 00 c2 c1 c0 d7 d6 d5 d4
        4: 00 d3 d2 d1 d0 e7 e6 e5
        5: 00 e4 e3 e2 e1 e0 f7 f6
        6: 00 f5 f4 f3 f2 f1 f0 g7
        7: 00 g6 g5 g4 g3 g2 g1 g0
Here is a C fragment to decode the data (note that you don't want to decode the SysEx status messsages; they are not encoded):
  unsigned char c, oc;

  oc = 0;
  for (i=0; ((c = getc(ifp)) < 0x80); i++) {
     i %= 147;			/* end of program */
     if (shift = i % 8) {
        oc = (oc << shift) + (c >> (7-shift));
        putc(oc, ofp);
     }
     oc = c;
  }
All the info given below assumes the data has been decoded. If you are going to send the data back to the QV after editing it, you have to encode it first. Code fragment left as an exercise for the reader.

QuadraVerb System Exclusive Command Format

Note you have to tell the QuadraVerb to accept MIDI SysEx data before any of this will work. Although it's possible to instruct the QV to disable SysEx via MIDI SysEx; it's not possible to re-enable it; you have to go do it from the front panel.

A QuadraVerb SysEx command string looks like (in hex):

    f0  - SysEx start
    00  \
    00   - Alesis mfr code 
    0e  /
    02  QuadraVerb ID number
    cc  QuadraVerb command code
    pp  QuadraVerb command code parameter
    dd  data stream (variable length)
    ..
    f7  End of SysEx
The command codes are:
    01 Change Parameter
    02 Load Program
    03 Dump Program
The parameters depend on the command and are discussed below.

Dump Program (command code 03)

To have an external device request a QuadraVerb program dump, send the following MIDI sequence to the QV:
       f0 00 00 0e 02 03 pp f7
where '03' is the "dump data" command, and 'pp' is the hex parameter:
       00-63  single program, 0-99
       64     edit buffer
       65     all program memory
Keep in mind if you're doing many edit/compares on program 27 you probably want to be dumping the edit buffer, not program 27, as #27 is only modified once the STORE is done.

Load Program (command code 02)

The format is similar:
       f0 00 00 0e 02 02 pp (data) f7
where 'pp' is the same as in the above description. The data must be encoded before being sent. If you do it right you should send 155 bytes out the MIDI port (including SysEx etc) for an individual program.

Change Parameter (command code 01)

       f0 00 00 0e 02 01 gg pp dd dd dd f7
where 'gg' is the 'parameter group' you want to change:
       00 - program
       01 - reverb
       02 - delay
       03 - pitch
       04 - eq
       05 - midi
       06 - store
       07 - config
       08 - mix
       09 - mod
       0a - name
and 'pp' is the parameter number within parameter group (for example in 'reverb', parameter number 0 is 'Reverb Type', and the numbers increase the same as if you used the PAGE UP key).

The "dd dd dd" string is the value you want in that parameter. It must be encoded, even if it fits in 7 bits. Sometimes the value takes two bytes; in that case they should be sent MSB first, then LSB (this is the opposite of the HR-16). When one byte is encoded it will become two bytes; likewise two become three. If you're sending two bytes (after encoding) send them first, then 00, then f7.

The QV will also send you these Change Parameter requests every time a parameter is changed using the front panel. If somebody selects the Delay Time parameter and pushes the button to go from 1 to 400ms, you're going to get 400 of these messages. You will get messages every time the VALUE buttons get pushed, even when nothing changes (like being in program mode and pressing the down key when you're already at program zero), so be prepared for them.

You can't send running parameter change requests; each one has to be a separate SysEx message.

QuadraVerb System Exclusive Program Format

A single program has 128 bytes of data. When it's encoded and shipped over MIDI, it's 147 bytes (without SysEx headers). That's why the decode fragment above has that magic number in it.

Unused locations have zeros in them. The EQ bytes change meaning depending on whether graphic EQ is being used, so both are given. Everything here is listed in decimal.

Graphic EQ parameters, only used in the Graphic_EQ->Delay configuration:

 Byte   Description            Default  Range
   0     ???                      ??    ?? [usually set to 14]
   1     16Hz                     14    0-28 (14 is center)
   2     32Hz                     14    0-28 (14 is center)
   3     62Hz                     14    0-28 (14 is center)
   4    126Hz                     14    0-28 (14 is center)
   5    250Hz                     14    0-28 (14 is center)
   6    500Hz                     14    0-28 (14 is center)
   7     1kHz                     14    0-28 (14 is center)
   8     2kHz                     14    0-28 (14 is center)
   9     4kHz                     14    0-28 (14 is center)
  10     8kHz                     14    0-28 (14 is center)
  11    16kHz                     14    0-28 (14 is center)
  12     ???                      ??    ?? [usually set to 24]
Graphic EQ also seems to change all modulation targets to 16Hz boost/cut.

Here's the complete list, in byte order. Note that all parameters have a 'default' value you can get by pressing both VALUE buttons at the same time - if you're building a patch editor you might want this info so your user can hit a button to get the default value for some parameter.

 Byte   Description            Default  Range
   0	Low EQ Frequency MSB
   1	Low EQ Frequency LSB     200  20-999Hz
   2	Low EQ Amplitude MSB
   3	Low EQ Amplitude LSB     280  0=-14db, 280=0db, 560=14db, 0.05 steps
   4	Low EQ Frequency MSB
   5	Mid EQ Frequency LSB    2000  200-9999Hz
   6	Mid EQ Bandwidth         100  20-255 (0.2-2.55 octaves)
   7	Mid EQ Amplitude MSB
   8	Mid EQ Amplitude LSB     280  0=-14db, 280=0db, 560=14db, 0.05 steps
   9	High EQ Frequency MSB
  10	High EQ Frequency LSB   8000  2000-18000Hz
  11	High EQ Amplitude MSB
  12	High EQ Amplitude LSB    280  0=-14db, 280=0db, 560=14db, 0.05 steps
  13	Leslie High Rotor Level   20  0=-20db, 26=+6db
  14	Low-Mid EQ Freq. MSB
  15	Low-Mid EQ Freq. LSB     100  20-500Hz       (really 100Hz default!)
  16	Low-Mid EQ Bandwidth     100  20-255 (0.2-2.55 octaves)
  17	Low-Mid EQ Ampl. MSB
  18	Low-Mid EQ Ampl. LSB     280  0=-14db, 280=0db, 560=14db, 0.05 steps
  19	High-Mid EQ Freq. MSB
  20	High-Mid EQ Freq. MSB   6000  2000-18000Hz
  21	High-Mid EQ Bandwidth    100  20-255 (0.2-2.55 octaves)
  22	High-Mid EQ Ampl. MSB
  23	High-Mid EQ Ampl. LSB    280  0=-14db, 280=0db, 560=14db, 0.05 steps
  24        [unused]
  25        [unused]
  26	Pitch Mode                 1  0-5 m/s_chorus, m/s_flange, phase, detune
  27	Pitch Input                1  0=pre-eq, 1=post-eq
  28	LFO Waveshape              0  0=triangle, 1=square
  29	LFO/Phaser Speed          20  0=1, 98=99
  30	LFO/Phaser Depth          50  0=1, 98=99
  31        [unused]
  32	Pitch Feedback (%)         0  0-99
  33	Detune Amount             99  0=-99, 99=none, 198=+99
  34	Leslie Stereo Separation  99  0-99
  35	Leslie Motor Control       1  0=off, 1=on
  36	Leslie Motor Speed         0  0=slow, 1=fast
  37	Trigger Flange             0  0=off, 1=on
  38        [unused]
  39	Delay Type                 1  0=mono, 1=stereo, 2=ping-pong
  40	Delay Input 1              1  0=pre-eq, 1=post-e1
  41	Delay Input Mix           99  0=input1, 99=center, 198=pitch/leslie
  42	Left Delay Time (MSB)         1-400ms (1-800ms mono)
  43	Left Delay Time (LSB)    100  If graphicEQ: 1-750ms (1-1500ms mono)
  44	Left Delay Feedback (%)    0  0-99
  45	Right Delay Time (MSB)        (Right not used in mono)
  46	Right Delay Time (LSB)   100  1-400ms (if graphicEQ: 1-750ms)
  47	Right Delay Feedback (%)   0  0-99
  48        [unused]
  49        [unused]
  50	Reverb Type                0  0=plate, 1=room, 2=chamber, 3=hall, 4=rev
  51        [unused]
  52	Reverb Input 1             3  0=pre-eq, 1=post-eq, 2=pitch, 3=delay_mix
  53	Reverb Input 2             1  0=pitch out, 1=delay out
  54	Reverb Input Mix           0  0=Input1, 99=center, 198=Input2
  55	Reverb PreDelay           40  1-140ms
  56	PreDelay Mix             198  0=Pre, 99=center, 198=Post
  57	Reverb Decay              50  0-99
  58	Reverb Diffusion Amount    8  0=1, 4=5, 8=9
  59	Low Frequency Decay       60  0=-60, 30=-30, 60=0
  60	High Frequency Decay      40  0=-60, 30=-30, 60=0
  61	Reverb Density             8  0=1, 4=5, 8=9
  62	Reverb Gate                0  0=off, 1=on
  63	Reverb Gate Hold Time      0  0-99
  64	Reverb Gate Release Time  80  0-99
  65	Reverb Gated Level (%)     0  0-99
  66        [unused]
  67        [unused]
  68	Configuration              0  0-4
  69	Direct Signal Select       0  0=pre-eq, 1=post-eq
  70	Direct/EQ Signal Level    99  0-99 (EQ Out if Direct Signal Select = 1)
  71	Master Effects Level      50  0-99
  72	Pitch/Leslie Out Level    50  0-99
  73	Delay Output Level        50  0-99
  74	Reverb Output Level       50  0-99
  75        [unused]
  76        [unused]
  77        [unused]
  78        [unused]
  79        [unused]
  80	Mod 1 Source               0  0-125 (see list below)
  81	Mod 1 Target               0  (see Modulation Targets section below)
  82	Mod 1 Amplitude            0  0=-99, 99=0, 198=+99
  83	Mod 2 Source
  84	Mod 2 Target                  Sources: 0=pitch_bend, 1=after_touch,
  85	Mod 2 Amplitude                        2=note_number, 3=note_velocity,
  86	Mod 3 Source                           4-125 correspond to MIDI
  87	Mod 3 Target                           controller numbers 0-121.
  88	Mod 3 Amplitude
  89	Mod 4 Source
  90	Mod 4 Target
  91	Mod 4 Amplitude
  92	Mod 5 Source
  93	Mod 5 Target
  94	Mod 5 Amplitude
  95	Mod 6 Source
  96	Mod 6 Target
  97	Mod 6 Amplitude
  98	Mod 7 Source
  99	Mod 7 Target
 100	Mod 7 Amplitude
 101	Mod 8 Source
 102	Mod 8 Target
 103	Mod 8 Amplitude
 104        [unused]
 105        [unused]
 106	Edit Name Character  1    32  The following 96 characters, in order:
 107	Edit Name Character  2         !"#$%&'()*+,-./0123456789:;<=>?
 108	Edit Name Character  3        @ABCDEFGHIJKLMNOPQRSTUVWXYZ[Y]^_
 109	Edit Name Character  4        `abcdefghijklmnopqrstuvwxyz{|}><
 110	Edit Name Character  5
 111	Edit Name Character  6        The second Y is the Japanese 'Yen' or
 112	Edit Name Character  7        Chinese 'Yuan' (monetary) symbol.  The
 113	Edit Name Character  8        last two characters are right and left
 114	Edit Name Character  9        arrows.  The backslash and tilde
 115	Edit Name Character 10        characters are not available.
 116	Edit Name Character 11
 117	Edit Name Character 12        Note this list is in ASCII order, and
 118	Edit Name Character 13        the ASCII equivalent is what's stored.
 119	Edit Name Character 14
 120        [unused]
 121        [unused]
 122        [unused]
 123        [unused]
 124        [unused]
 125        [unused]
 126        [unused]
 127        [unused]

Modulation Targets

The target numbers are not constant; it depends on what configuration you are using, so you can't always change the target to #48 and know it always means your modulator affects Low EQ Frequency. What a pain.
  0	Reverb Input Mix
  1	Reverb PreDelay
  2	Reverb PreDelay Mix
  3	Reverb Reverse Time	(Reverb Decay?  I think the LCD mislabels this)
  4	Reverb Diffusion
  5	Reverb Density
  6	Reverb Low Decay
  7	Reverb High Decay

 16	Delay Input Mix		(L/Mono Delay Time if GraphicEQ)
 17	L/Mono Delay Time	(L/Mono Delay Feedback if GraphicEQ)
 18	L/Mono Delay Feedback	(R Delay Time if GraphicEQ)
 19	R Delay Time		(R Delay Feedback if GraphicEQ)
 20	R Delay Feedback

 32	LFO/Phaser Speed	(Leslie Stereo)
 33	LFO/Phaser Depth	(Leslie Motor)
 34	Pitch Feedback		(Leslie Speed)

 48	Low EQ Frequency	(16Hz boost/cut)	(Leslie High Level)
 49	Low EQ Amplitude	(32Hz boost/cut)
 50	Mid EQ Frequency	(62Hz boost/cut)	(Low-Mid EQ Frequency)
 51	Mid EQ Bandwidth	(126Hz boost/cut)	(Low-Mid EQ Width)
 52	Mid EQ Amplitude	(250Hz boost/cut)	(Low-Mid EQ Amplitude)
 53	High EQ Frequency	(500Hz boost/cut)	(Mid EQ Frequency)
 54	High EQ Amplitude	(1kHz boost/cut)	(Mid EQ Bandwidth)
 55				(2kHz boost/cut)	(Mid EQ Amplitude)
 56				(4kHz boost/cut)	(High-Mid EQ Frequency)
 57				(8kHz boost/cut)	(High-Mid EQ Bandwidth)
 58				(16kHz boost/cut)	(High-Mid EQ Amplitude)
 59							(High EQ Frequency)
 60							(High EQ Amplitude)

 64	Direct/EQ Mix Level	(Effect Mix Level if GraphicEQ)
 65	Effect Mix Level	(EQ Mix Level if GraphicEQ)
 66	Pitch/Leslie Mix Level	(Delay Mix if GraphicEQ, Reverb Mix if cfg 5)
 67	Delay Mix Level
 68	Reverb Mix Level

Full Program Dump Format

A full dump is all 100 programs, end to end. HOWEVER, the MIDI encoding starts over at each program (that's why you see the i %= 147 statement in the decoding fragment above). The edit buffer is not dumped on a full dump, so after decoding, your data should have 12800 bytes.

No MIDI parameters are ever dumped, and there is no checksum information. I don't know how to get the version of the ROM (without opening the case).

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