Novation X-Station User Manual page 13

MIDI TUTORIAL
To calculate the MSB, divide the full NRPN number by 128. The
remainder is the LSB value.
Once the LSB & MSB of the NRPN number have been sent, CC6
(known as Data Entry) immediately follows. This contains the actual
data value to be sent in the NRPN.
As an example of how this works, consider sending a data value of 10
on NRPN number 260. The three grouped Continuous Controller mes-
sages would be :
CC98 (NRPN LSB) 4
CC99 (NRPN MSB) 2
CC6 (Data Entry) 10
Many synthesizers do not use NRPNs. Consult your synthesizer manu-
al for details of which NRPNs are recognised.
The use of NRPNs is detailed on page 17.
Registered Parameter Messages
These are known as RPNs and are similar in format to NRPN mes-
sages. CC100 is used to define the RPN LSB and CC101, the RPN
MSB (usually zero). As for NRPNs, CC6 contains the actual data value.
RPN numbers assigned by the MIDI specification are :
0 Pitch Bend sensitivity
1 Fine Tuning
2 Coarse Tuning
3 Tuning Program Select
4 Tuning Bank Select
Many synthesizers do not use RPNs. Consult your synthesizer manual
for details of which RPNs are recognised.
The use of RPNs is detailed on page 17.
Pitch Bend Messages
These messages are transmitted whenever the X-Station's joystick is
moved along the X axis. It is also possible to define the X - Y touchpad
to transmit Pitch Bend.
As the name implies, pitch bend messages are used to move sounding
notes up or down in pitch.
Aftertouch Messages
These messages are transmitted by some keyboards whenever
already-held down keyboard notes are pushed further or wiggled.
Aftertouch messages can be used to add extra expressiveness to a
sound, for example introducing an extra vibrato effect.
The MIDI specification actually defines two different types of aftertouch
message; Mono and Poly. The type transmitted by the X-Station is the
Mono type. This affects all sounding notes simultaneously.
Poly aftertouch includes information in the MIDI message about which
keyboard note was used to trigger the aftertouch effect, allowing individ-
ual sounding notes to be affected. Poly aftertouch is actually very rarely
found nowadays as only a very few synthesizers ever used it.
Program Change & Bank Select Messages
These messages are used to remotely select sounds on a synthesizer.
The MIDI Specification only allows a MIDI program change message to
select one of 128 different sounds. When the MIDI specification was
originally designed, this was rarely a problem since synthesizers sel-
dom had more than 128 memories. Modern synthesizers such as the
Novation K-Station offer many more memories than this (the K-Station
for example, actually has 400 memories divided into four 'banks' of 100
memories each), so it is often convenient to send a MIDI program
change preceded by an additional MIDI message which specifies which
'bank' of sounds the following Program Change message will select
from.
(260 modulus 128 = 4)
(260 / 128 = 2)
(data value)
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The Bank Select MIDI message used for this purpose is actually a MIDI
Control Change message. CC32 is the control change number used by
Novation and most manufacturers, but a few manufacturers may use
CC0 instead. Consult the synthesizer manual for details on the Bank
Select Continuous Controller number used.
For example to select Program A100 on the Novation Supernova, the
following MIDI messages would be needed :
CC32 5 (5 selects Program Bank A on the Supernova)
Prog Change 100
Synthesizers which implement Bank Select usually require that the
appropriate Bank Select message is sent before a following Program
Change message. Synthesizers not implementing Bank Select need
only receive a Program Change message.
Warning : Many synthesizers will only accept a Program Change
message if a Bank Select message has been received first !
Bank Select Messages may be sent from the X-Station by either using
the DATA / VALUE encoder from from within Play Mode (CC32 is
always sent) or by defining a control within a Template to transmit CC0
or CC32 as appropriate.
Program Change messages may be sent from the X-Station by either
using the PROG / PAGE UP / DOWN buttons from within Play Mode or
by defining a control within a Template to transmit Program Change.
Channel Messages
All of the different types of MIDI messages outlined so far include infor-
mation detailing which MIDI channel was used when the message was
transmitted. MIDI channel messages will only affect receiving devices
using the same MIDI channel. For example, a Pitch Bend message
sent using MIDI channel 1 would have no effect at all if it were received
on a synthesizer set to respond on MIDI channel 2.
Some MIDI messages do not include any MIDI channel information
defined in them. Some examples of these are :
System Exclusive Messages
This is special type of MIDI message, often referred to as 'Sysex'.
System Exclusive messages can actually contain any type of data,
depending what the synthesizer manufacturer decides to put in it! The
only constraint with system exclusive messages is that they always
contain certain header information which is exclusively used by the
manufacturer (and usually the relevant synth model as well). What this
effectively means is that a MIDI device will only accept a system exclu-
sive message designed especially for it. For example, If the Novation
K-Station should receive a system exclusive message transmitted by a
different make of synthesizer, the message would simply be ignored.
Similarly, other makes of synthesizer will ignore any system exclusive
messages originally sent by a Novation K-Station.
Unlike other types of MIDI message, System Exclusive messages do
not have a fixed length. The MIDI specification allows any number of
data bytes (each with a value between 0 to 127) between a Sysex
Start byte and a Sysex End byte. The first data bytes in a Sysex mes-
sage always contain the manufacturer ID. This is unique to each
Synthesizer manufacturer.
Some manufacturers (such as Yamaha) employ short Sysex messages
for sound editing purposes rather than using Control Change mes-
sages. The X-Station can send short System Exclusive messages con-
taining up to 20 bytes (including the manufacturer ID). See page 18 for
details.
The X-Station employs system exclusive messages for two distinct pur-
poses. Firstly, they can be used to back up all of the X-Station memo-
ries and global data. This feature is extremely useful in building up a
Template library or a Synth program library on a computer or for making
a safety copy of data in case the worst should happen. Data backup is
discussed in detail on Page 25 in the Advanced Features chapter.
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MIDI Messages