MIDI
eMagic MIDI drivers
Apple no longer support eMagic products and the USB MIDI drivers are not easily found online. Here are versions 2.2, 2.3 and 2.5. These work on an MT4 MIDI interface and OSX 10.5. Versions 10.6 and 10.7 of the Mac OS are not supported.
| emagic_usb_drivers.zip |
Using MainStage with Pro Tools or Logic
If you want to use a MainStage Instrument or two from within Pro Tools or Logic, here is how to set it up:
| using_iac.pdf |
Alesis QX49 controller mapping in Logic
| qx49___controller_mapping_in_logic_pro.pdf |
3 MIDI software reviews
| metro_review.pdf |
| noteability_pro_ii.pdf |
| music_ace.pdf |
Polyphony and Multi-timbre
Polyphony is used to state how many notes can sound simultaneously from a MIDI keyboard or sound module. In the early days synthesisers were mono-phonic meaning only one key could sound at a time. Note priority could be low note, high note, or last note (this one being the only musically sensible one). As things developed the polyphony increased, firstly to two note (duo-phonic), then 4 note, 5, 6, and 8 note. The Yamaha DX7 made a breakthough in 1983 by offering 16 note polyphony for around $2000 (not to mention FM synthesis and velocity sensing). Since then polyphony has become a non-issue for many keyboard players (there are not a lot of duets performed on a synthesiser). Recently there has been a resurged interest in analogue synthesis and some of the current budget devices have limited polyphony eg the Korg MS2000 is a 4 voice synthesiser.
Multi-timbral means a MIDI device is able to play different sounds simultaneously. For example a 16 part multitimbral sound module can play 16 different sounds together. One “part” could also be drums where each note plays a different sound. An orchestra in a box. Note stealing describes the condition where the polyphony limit has been exceeded. This can occur when playing back from a multitrack MIDI sequencer. Modern sound modules dynamically allocate the available notes across the parts, and the first note on will be the first note off. For example: a sequence sends to a 16 note device. It starts with a 16 bar bass drone. At bar 13, seventeen notes try to play at the same resulting in the bass note dropping out.
The word “voice” is often also used but this is no longer the same thing as polyphony. For example a synth may have 64 voices, but if 4 voices are layered to make a sound then the polyphony is reduced to 16 notes.
Multi-timbral means a MIDI device is able to play different sounds simultaneously. For example a 16 part multitimbral sound module can play 16 different sounds together. One “part” could also be drums where each note plays a different sound. An orchestra in a box. Note stealing describes the condition where the polyphony limit has been exceeded. This can occur when playing back from a multitrack MIDI sequencer. Modern sound modules dynamically allocate the available notes across the parts, and the first note on will be the first note off. For example: a sequence sends to a 16 note device. It starts with a 16 bar bass drone. At bar 13, seventeen notes try to play at the same resulting in the bass note dropping out.
The word “voice” is often also used but this is no longer the same thing as polyphony. For example a synth may have 64 voices, but if 4 voices are layered to make a sound then the polyphony is reduced to 16 notes.
Block diagram of an MIDI (and audio) post production suite for music:
| midi_suite.pdf |
GM2
General MIDI Level 2 (GM2) was introduced in 1999 in response to some manufacturers already adding features to GM products. The Roland GS (General Standard) was being used on the Sound Canvas and Yamaha had XG (Extended General MIDI) on the TG series sound modules. General MIDI level 2 was adopted to provide a similar enhancement of General MIDI, and discourage proprietary development away from the MIDI standard.
In comparison to General MIDI, GM2 has twice a many sounds and to maintain compatibility with GM the extra sounds are accessed using bank select commands (cc0 and cc32). The number of voices was increased to 32, which also include the maximum number of simultaneous drum sounds to be 16 (in GM it was 8). Each drum kit has an extra 14 sounds and channel 11 is permitted to be a drum channel as well as channel 10. The number of drum kits is increased from one to ten.
The number of controllers in GM2 is 23 compared to 11 in GM. The most useful of these are bank select, reverb level and chorus level (all of these were in both the XG and GS specifications). Additional controllers for filter, dynamics, and modulation have also been included. The number of System Exclusive Messages was increased from two to fourteen.
In comparison to General MIDI, GM2 has twice a many sounds and to maintain compatibility with GM the extra sounds are accessed using bank select commands (cc0 and cc32). The number of voices was increased to 32, which also include the maximum number of simultaneous drum sounds to be 16 (in GM it was 8). Each drum kit has an extra 14 sounds and channel 11 is permitted to be a drum channel as well as channel 10. The number of drum kits is increased from one to ten.
The number of controllers in GM2 is 23 compared to 11 in GM. The most useful of these are bank select, reverb level and chorus level (all of these were in both the XG and GS specifications). Additional controllers for filter, dynamics, and modulation have also been included. The number of System Exclusive Messages was increased from two to fourteen.
MIDI Timeline
The MIDI standard stretches all the way back to before 1983. Just when was the Sample Dump Standard introduced? Find out here:
| midi_timeline.pdf |
MIDI Thru
The MIDI specification has a point-to-point connection protocol. A single unidirectional link is made between two MIDI devices (ie from MIDI OUT to MIDI IN). Most devices also provide a MIDI THRU so a third device can be connected. The MIDI THRU socket is taken internally from the electrical signal presented at the MIDI IN socket. Simply using a Y cable will result in failure of MIDI data transfer. Several MIDI devices can be daisy-chained, from MIDI THRU to MIDI IN.
The advantage in live performance is that a keyboard player can address a whole rack of MIDI sound modules from one keyboard controller. This presents an uncluttered look on stage, and provides for performing from a single position.
Notes: 1. some manufactures and texts have used the term MIDI THRU to identify an internal connection from MIDI IN to MIDI OUT. To avoid such confusion MIDI MERGE is preferred.
2. a MIDI THRU BOX can also be used to connect to multiple devices. It has a MIDI IN and several MIDI OUT sockets. It has no MIDI THRU (the name arises from the sound module function it replaces).
The advantage in live performance is that a keyboard player can address a whole rack of MIDI sound modules from one keyboard controller. This presents an uncluttered look on stage, and provides for performing from a single position.
Notes: 1. some manufactures and texts have used the term MIDI THRU to identify an internal connection from MIDI IN to MIDI OUT. To avoid such confusion MIDI MERGE is preferred.
2. a MIDI THRU BOX can also be used to connect to multiple devices. It has a MIDI IN and several MIDI OUT sockets. It has no MIDI THRU (the name arises from the sound module function it replaces).
