GSI VB3-II MIDI CC chart, NRPN and OSC map¶
The GSI VB3-II MIDI implementation: 54 CC, each named, for Claude (MCP), SuperCollider or any OSC app.
| Device | GSI VB3-II |
|---|---|
| Vendor | GSi |
| OSC prefix | /gsi_vb3_ii |
| Source | 🎛️ Derived from an Electra One community preset |
| Revision | per Electra preset |
| Upstream | electra-preset |
| Driver file | devices/gsi/gsi_vb3_ii.json |
Not tested on the device yet
This driver comes from documentation or community data and has not been checked on real hardware. If you own one, a quick test and a pull request promoting it helps everyone — see CONTRIBUTING.
How do you control it?¶
Find the MIDI ports, then start the bridge with this driver:
osc-bridge detect # prints the ready-to-run line for what is plugged in
osc-bridge run --device devices/gsi/gsi_vb3_ii.json --out-port <N> --in-port <M>
Then send OSC to 127.0.0.1:7777, for example:
From Claude or any MCP client, the osc-bridge mcp server exposes this driver as gsi_vb3_ii: ask “what can the GSI VB3-II do?” and it reads this map with list_routes. See the MCP guide.
MIDI CC and NRPN parameters (54)¶
| OSC address | CC | NRPN (MSB/LSB) | Range | Nature | Section |
|---|---|---|---|---|---|
/gsi_vb3_ii/volume |
7 | 0–127 | continuous | ||
/gsi_vb3_ii/bass |
8 | 0–127 | continuous | ||
/gsi_vb3_ii/treble |
10 | 0–127 | continuous | ||
/gsi_vb3_ii/keyclick |
75 | 0–127 | continuous | ||
/gsi_vb3_ii/drive |
76 | 0–127 | continuous | ||
/gsi_vb3_ii/reverb |
91 | 0–127 | continuous | ||
/gsi_vb3_ii/leslie_on_off |
85 | 0–127 | continuous | ||
/gsi_vb3_ii/speed |
1 | 0–127 | continuous | ||
/gsi_vb3_ii/off_on |
66 | 0–127 | continuous | ||
/gsi_vb3_ii/normal_soft |
70 | 0–127 | continuous | ||
/gsi_vb3_ii/slow_fast |
71 | 0–127 | continuous | ||
/gsi_vb3_ii/second_third |
72 | 0–127 | continuous | ||
/gsi_vb3_ii/16 |
12 | 0–8 | continuous | ||
/gsi_vb3_ii/5_1_3 |
13 | 0–8 | continuous | ||
/gsi_vb3_ii/8 |
14 | 0–8 | continuous | ||
/gsi_vb3_ii/4 |
15 | 0–8 | continuous | ||
/gsi_vb3_ii/2_2_3 |
16 | 0–8 | continuous | ||
/gsi_vb3_ii/2 |
17 | 0–8 | continuous | ||
/gsi_vb3_ii/soft_normal |
32 | 0–127 | continuous | ||
/gsi_vb3_ii/on_off |
31 | 0–127 | continuous | ||
/gsi_vb3_ii/1_3_5 |
18 | 0–8 | continuous | ||
/gsi_vb3_ii/1_1_3 |
19 | 0–8 | continuous | ||
/gsi_vb3_ii/1 |
20 | 0–8 | continuous | ||
/gsi_vb3_ii/16 |
21 | 0–8 | continuous | ||
/gsi_vb3_ii/5_1_3 |
22 | 0–8 | continuous | ||
/gsi_vb3_ii/8 |
23 | 0–8 | continuous | ||
/gsi_vb3_ii/4 |
24 | 0–8 | continuous | ||
/gsi_vb3_ii/2_2_3 |
25 | 0–8 | continuous | ||
/gsi_vb3_ii/2 |
26 | 0–8 | continuous | ||
/gsi_vb3_ii/vibrato_chorus |
73 | 0–127 | continuous | ||
/gsi_vb3_ii/on_off |
30 | 0–127 | continuous | ||
/gsi_vb3_ii/1_3_5 |
27 | 0–8 | continuous | ||
/gsi_vb3_ii/1_1_3 |
28 | 0–8 | continuous | ||
/gsi_vb3_ii/1 |
29 | 0–8 | continuous | ||
/gsi_vb3_ii/16 |
40 | 0–8 | continuous | ||
/gsi_vb3_ii/5_1_3 |
41 | 0–8 | continuous | ||
/gsi_vb3_ii/8 |
42 | 0–8 | continuous | ||
/gsi_vb3_ii/4 |
43 | 0–8 | continuous | ||
/gsi_vb3_ii/2_2_3 |
44 | 0–8 | continuous | ||
/gsi_vb3_ii/2 |
45 | 0–8 | continuous | ||
/gsi_vb3_ii/1_3_5 |
46 | 0–8 | continuous | ||
/gsi_vb3_ii/1_1_3 |
47 | 0–8 | continuous | ||
/gsi_vb3_ii/1 |
48 | 0–8 | continuous | ||
/gsi_vb3_ii/16 |
50 | 0–8 | continuous | ||
/gsi_vb3_ii/5_1_3 |
51 | 0–8 | continuous | ||
/gsi_vb3_ii/8 |
52 | 0–8 | continuous | ||
/gsi_vb3_ii/4 |
53 | 0–8 | continuous | ||
/gsi_vb3_ii/2_2_3 |
54 | 0–8 | continuous | ||
/gsi_vb3_ii/2 |
55 | 0–8 | continuous | ||
/gsi_vb3_ii/1_3_5 |
56 | 0–8 | continuous | ||
/gsi_vb3_ii/1_1_3 |
57 | 0–8 | continuous | ||
/gsi_vb3_ii/1 |
58 | 0–8 | continuous | ||
/gsi_vb3_ii/16 |
33 | 0–8 | continuous | ||
/gsi_vb3_ii/8 |
35 | 0–8 | continuous |
Performance MIDI¶
Notes, pitch bend and any CC are also available: /gsi_vb3_ii/note/on <note> <velocity>, /gsi_vb3_ii/cc/<number> <value>, /gsi_vb3_ii/pitchbend <0-16383>, /gsi_vb3_ii/program_change <n>.
Limitations¶
Imported from an Electra One community preset. The mapping reflects the preset author's editorial choices: parameter naming, ranges, and which params are exposed. Untested on hardware in this repo.
Frequently asked questions¶
How many parameters of the GSI VB3-II can be controlled over MIDI?
SynthHub's map of the GSI VB3-II lists 54 MIDI CC parameters, each with its number, range and a readable name; the full chart is on this page.
Can an AI agent like Claude control the GSI VB3-II?
Yes: SynthHub's hosted MCP server knows the GSI VB3-II's MIDI map, and its browser relay lets the agent send it parameter changes or load a sound, each sound change confirmed by you.