User manual
Quattro. User Manual
19
4. APENDIX
4.1. MIDI Specification
A DJ Software have the “mapping” function that assigns MIDI
messages to the different functions of the DJ Software.
We also have to match the DJ Software functions with the
controls of the external device (the controller). We do so by
assigning the DJ Software function and the control the same
MIDI note or message.
Every QUATTRO control generates various MIDI messages
you can see at the table QUATTRO MIDI MAP. We can send
the MIDI messages through channels 0 to 15, this is a MIDI
standard. We can see four different parts on a MIDI message:
- The MIDI code (MIDI CODE) lets us know what type of
message is sent.
- The MIDI code (MIDI CODE) + Channel lets us know what
type of message is sent again and the channel which it is sent
through.
- The FUNCTION CODE gives us the note or control value.
- The action let us know the value that the control attains when
is manipulated.
At the table those parts are separated by commas in the MIDI
COMMAND columns.
DJ Software’s use two types of MIDI codes:
- “Control Note” (switch): the control is a switch (you see a
button) or a LED and will look like NOTE C2. Each note has a
number that at the table is expressed in Hexadecimal (HEX).
Further on this manual we will explain how notes and numbers
correspond to each other and how to change from
hexadecimal to decimal. In this case MIDI CODE is 9 and
FUNCTION CODE is the note of the control.
- “Control Change” (CC): the control will be a potentiometer or
encoder and will have a label like Cc53. In this case MIDI
CODE is B and FUNCTION CODE is a value between 0 and
127. We will associate a value to each control of the kind.
Upon the value of the action part of the MIDI message we will
classify the controls as follows:
a- NOTE-KEY: are note type messages. Action value can be
127 (7FH) when we press or 0 when we release.
b- NOTE-LED: determines the LED that will light, are note type
messages as the switches and the values are 127 for LED ON
and 0 for LED OFF. In the LEDs case it is the DJ Software that
sends the MIDI messages to the controller.
c- CC-ABSOLUTE (VR) - CC “Control Change” Absolute.
These are potentiometer like controls. The action value is a
number between 0 and 127 upon the potentiometer position.
d- CC-RELATIVE (ENCODER/WHEEL) - CC “Control Change”
Relative. These are encoder like controls. As oppose to the
potentiometer that encoder does not send a message to report
its position but only report changes when turning to clockwise
or anticlockwise. It is sent the value 63 (3FH) if it turns to the
left and 65 (41H) if it turns to the right.
e- CC-LEVEL LED. The value sent in the action from 0 to 127
will tell how many LEDs have to be turned ON at the vu-meter.
There are DJ Software’s where it is not necessary to know
note values or control values because the software “read”
them automatically and by touching a control it assigns its note
to a certain function selected by the user.
In other Software’s it is necessary to write by hand the values.
Even in Software’s with auto learn function you must
write/select the LEDs. Therefore, we recommend you try
understanding the QUATTRO MIDI MAP table.
Note: the MIDI MAP is presented in hexadecimal base >
NOTE or CC. To assign physical control to software functions
you need to translate the MIDI MAP into decimal base.
Following, we explain how to find out the equivalence between
Hexadecimal and Decimal:
0H
1H
2H
3H
4H
5H
6H
7H 8H 9H AH
BH
CH
DH
EH
FH
0H
0
16
32
48
64
80
96
112
128
144
160
176
192
208
224
240
1H
1
17
33
49
65
81
97
113
129
145
161
177
193
209
225
241
2H
2
18
34
50
66
82
98
114
130
146
162
178
194
210
226
242
3H
3
19
35
51
67
83
99
115
131
147
163
179
195
211
227
243
4H
4
20
36
52
68
84
100
116
132
148
164
180
196
212
228
244
5H
5
21
37
53
69
85
101
117
133
149
165
181
197
213
229
245
6H
6
22
38
54
70
86
102
118
134
150
166
182
198
214
230
246
7H
7
23
39
55
71
87
103
119
135
151
167
183
199
215
231
247
8H
8
24
40
56
72
88
104
120
136
152
168
184
200
216
232
248
9H
9
25
41
57
73
89
105
121
137
153
169
185
201
217
233
249
AH
10
26
42
58
74
90
106
122
138
154
170
186
202
218
234
250
BH
11
27
43
59
75
91
107
123
139
155
171
187
203
219
235
251
CH
12
28
44
60
76
92
108
124
140
156
172
188
204
220
236
252
DH
13
29
45
61
77
93
109
125
141
157
173
189
205
221
237
253
EH
14
30
46
62
78
94
110
126
142
158
174
190
206
222
238
254
FH
15
31
47
63
79
95
111
127
143
159
175
191
207
223
239
255
To translate a 2 digit Hexadecimal base number into a Decimal
base we have to:
- find the column that has the digit that appears at the left.
- find the row that has the right digit.
- the convergence of row and column is the equivalent Decimal
number.
Inversely to translate a Decimal base number into a
Hexadecimal base we have to:
- find the number at the table. Its column is the first
hexadecimal digit, the second hexadecimal digit is it row.
E.g. Play control MIDI address is 33. Find the Decimal
equivalence at the Hexa-Dec table: Column 4 / Row 4 it is
decimal number 51.
Some softwares require not only knowing the decimal value
but also the corresponding note (for control change the
decimal number is enough). We can perform the Note-Decimal
number equivalence using the following table:
Octave #
Note Numbers
C C#
D D#
E F F# G G# A A#
B
-1
0 1 2 3 4 5 6 7 8 9 10
11
0
12
13
14
15
16 17 18 19 20 21
22
23
1
24
25
26
27
28 29 30 31 32 33
34
35
2
36
37
38
39
40 41 42 43 44 45
46
47
3
48
49
50
51
52 53 54 55 56 57
58
59
4
60
61
62
63
64 65 66 67 68 69
70
71
5
72
73
74
75
76 77 78 79 80 81
82
83
6
84
85
86
87
88 89 90 91 92 93
94
95
7
96
97
98
99
100
101
102
103
104
105
106
107
8
108
109
110
111
112
113
114
115
116
117
118
119
9
120
121
122
123
124
125
126
127
To find the note associated to a decimal number just take the
column where the number is as the note and the row is the
octave. Following the example presented before the
corresponding note to Play (decimal 51) button is D#3.
As seen at SHIFT+ column of the MIDI table, some QUATTRO
controls can send two different messages upon the state of the
Shift button.
The MIDI note associated with the same control of two
different decks is the same but notes are sent through different
MIDI channels. Deck A messages are sent through the
channel 0, deck B through the channel 1 and so on. Mixer
messages are sent through the channel 4.