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Rhodes Chroma 2 MIDI CC chart, NRPN and OSC map

The Rhodes Chroma 2 MIDI implementation: 158 CC, each named, for Claude (MCP), SuperCollider or any OSC app.

Device Rhodes Chroma 2
Vendor Rhodes
OSC prefix /chroma_2
Source πŸŽ›οΈ Derived from an Electra One community preset
Revision per Electra preset
Upstream electra-preset
Driver file devices/rhodes/chroma_2.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 β€” 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/rhodes/chroma_2.json --out-port <N> --in-port <M>

Then send OSC to 127.0.0.1:7777, for example:

osc-bridge osc-send /chroma_2/tune 31

From Claude or any MCP client, the osc-bridge mcp server exposes this driver as chroma_2: ask β€œwhat can the Rhodes Chroma 2 do?” and it reads this map with list_routes. See the MCP guide.

MIDI CC and NRPN parameters (158)

OSC address CC NRPN (MSB/LSB) Range Nature Section
/chroma_2/tune 30 0–63 continuous
/chroma_2/wave_shape 37 0–127 continuous
/chroma_2/mod_select 39 0–127 continuous
/chroma_2/tune 90 0–63 continuous
/chroma_2/wave_shape 97 0–127 continuous
/chroma_2/mod_select 99 0–127 continuous
/chroma_2/width 38 0–63 continuous
/chroma_2/mod_depth 40 -64–63 continuous
/chroma_2/width 98 0–63 continuous
/chroma_2/mod_depth 100 -64–63 continuous
/chroma_2/mod1_select 31 0–127 continuous
/chroma_2/mod2_select 33 0–127 continuous
/chroma_2/mod3_select 35 0–127 continuous
/chroma_2/mod1_select 91 0–127 continuous
/chroma_2/mod2_select 93 0–127 continuous
/chroma_2/mod3_select 95 0–127 continuous
/chroma_2/mod1_depth 32 -64–63 continuous
/chroma_2/mod2_depth 34 -64–63 continuous
/chroma_2/mod3_depth 36 -64–63 continuous
/chroma_2/mod1_depth 92 -64–63 continuous
/chroma_2/mod2_depth 94 -64–63 continuous
/chroma_2/mod3_depth 96 -64–63 continuous
/chroma_2/rate 10 0–31 continuous
/chroma_2/shape 11 0–127 continuous
/chroma_2/rate 70 0–31 continuous
/chroma_2/shape 71 0–127 continuous
/chroma_2/patch 115 0–127 continuous
/chroma_2/key_algorithm 117 0–127 continuous
/chroma_2/detune 118 0–31 continuous
/chroma_2/footsw_mode 116 0–127 continuous
/chroma_2/output_select 119 0–127 continuous
/chroma_2/type 41 0–127 continuous
/chroma_2/resonance 42 0–7 continuous
/chroma_2/tune 43 0–63 continuous
/chroma_2/type 101 0–127 continuous
/chroma_2/resonance 102 0–7 continuous
/chroma_2/tune 103 0–63 continuous
/chroma_2/mod1_select 44 0–127 continuous
/chroma_2/mod2_select 46 0–127 continuous
/chroma_2/mod3_select 48 0–127 continuous
/chroma_2/mod1_select 104 0–127 continuous
/chroma_2/mod2_select 106 0–127 continuous
/chroma_2/mod3_select 108 0–127 continuous
/chroma_2/mod1_depth 45 -64–63 continuous
/chroma_2/mod2_depth 47 -64–63 continuous
/chroma_2/mod3_depth 49 -64–63 continuous
/chroma_2/mod1_depth 105 -64–63 continuous
/chroma_2/mod2_depth 107 -64–63 continuous
/chroma_2/mod3_depth 109 -64–63 continuous
/chroma_2/mod1_select 50 0–127 continuous
/chroma_2/mod2_select 52 0–127 continuous
/chroma_2/mod3_select 54 0–127 continuous
/chroma_2/mod1_select 110 0–127 continuous
/chroma_2/mod2_select 112 0–127 continuous
/chroma_2/mod3_select 114 0–127 continuous
/chroma_2/mod1_depth 51 0–15 continuous
/chroma_2/mod2_depth 53 0–15 continuous
/chroma_2/mod1_depth 111 0–15 continuous
/chroma_2/mod2_depth 113 0–15 continuous
/chroma_2/attack 18 0–31 continuous
/chroma_2/attack_mod 19 0–127 continuous
/chroma_2/ampl_touch 17 0–127 continuous
/chroma_2/attack 78 0–31 continuous
/chroma_2/attack_mod 79 0–127 continuous
/chroma_2/ampl_touch 77 0–127 continuous
/chroma_2/decay 20 0–31 continuous
/chroma_2/decay_mod 21 0–127 continuous
/chroma_2/release 22 0–31 continuous
/chroma_2/decay 80 0–31 continuous
/chroma_2/decay_mod 81 0–127 continuous
/chroma_2/release 82 0–31 continuous
/chroma_2/delay 23 0–31 continuous
/chroma_2/env_2a 25 0–31 continuous
/chroma_2/env_2a 27 0–31 continuous
/chroma_2/env_2a 29 0–31 continuous
/chroma_2/delay 83 0–31 continuous
/chroma_2/env_2b 85 0–31 continuous
/chroma_2/env_2b 87 0–31 continuous
/chroma_2/env_2b 89 0–31 continuous
/chroma_2/attack_mod 26 0–127 continuous
/chroma_2/ampl_touch 24 0–127 continuous
/chroma_2/attack_mod 86 0–127 continuous
/chroma_2/ampl_touch 84 0–127 continuous
/chroma_2/decay_mod 28 0–127 continuous
/chroma_2/decay_mod 88 0–127 continuous
/chroma_2/mode 12 0–127 continuous
/chroma_2/rate 13 0–63 continuous
/chroma_2/rate_mod 14 0–127 continuous
/chroma_2/mode 72 0–127 continuous
/chroma_2/rate 73 0–63 continuous
/chroma_2/rate_mod 74 0–127 continuous
/chroma_2/wave_shape 15 0–127 continuous
/chroma_2/ampl_mod 16 0–127 continuous
/chroma_2/wave_shape 75 0–127 continuous
/chroma_2/ampl_mod 76 0–127 continuous
/chroma_2/waveshape 37 0–127 continuous
/chroma_2/waveshape 97 0–127 continuous
/chroma_2/mod_select_1 31 0–127 continuous
/chroma_2/mod_select_2 33 0–127 continuous
/chroma_2/mod_select_3 35 0–127 continuous
/chroma_2/mod_select_1 91 0–127 continuous
/chroma_2/mod_select_2 93 0–127 continuous
/chroma_2/mod_select_3 95 0–127 continuous
/chroma_2/mod_depth_1 32 -64–63 continuous
/chroma_2/mod_depth_2 34 -64–63 continuous
/chroma_2/mod_depth_3 36 -64–63 continuous
/chroma_2/mod_depth_1 92 -64–63 continuous
/chroma_2/mod_depth_2 94 -64–63 continuous
/chroma_2/mod_depth_3 96 -64–63 continuous
/chroma_2/glide_shape 11 0–127 continuous
/chroma_2/glide_rate 10 0–31 continuous
/chroma_2/glide_shape 71 0–127 continuous
/chroma_2/glide_rate 70 0–31 continuous
/chroma_2/cutoff 43 0–63 continuous
/chroma_2/filter_type 41 0–127 continuous
/chroma_2/cutoff 103 0–63 continuous
/chroma_2/filter_type 101 0–127 continuous
/chroma_2/mod_select_1 44 0–127 continuous
/chroma_2/mod_select_2 46 0–127 continuous
/chroma_2/mod_select_3 48 0–127 continuous
/chroma_2/mod_select_1 104 0–127 continuous
/chroma_2/mod_select_2 106 0–127 continuous
/chroma_2/mod_select_3 108 0–127 continuous
/chroma_2/mod_depth_1 45 -64–63 continuous
/chroma_2/mod_depth_2 47 -64–63 continuous
/chroma_2/mod_depth_3 49 -64–63 continuous
/chroma_2/mod_depth_1 105 -64–63 continuous
/chroma_2/mod_depth_2 107 -64–63 continuous
/chroma_2/mod_depth_3 109 -64–63 continuous
/chroma_2/mod_select_1 50 0–127 continuous
/chroma_2/mod_select_2 52 0–127 continuous
/chroma_2/mod_select_3 54 0–127 continuous
/chroma_2/mod_select_1 110 0–127 continuous
/chroma_2/mod_select_2 112 0–127 continuous
/chroma_2/mod_select_3 114 0–127 continuous
/chroma_2/mod_depth_1 51 0–15 continuous
/chroma_2/mod_depth_2 53 0–15 continuous
/chroma_2/mod_depth_1 111 0–15 continuous
/chroma_2/mod_depth_2 113 0–15 continuous
/chroma_2/env_1a_attack 18 0–31 continuous
/chroma_2/env_1a_decay 20 0–31 continuous
/chroma_2/env_1a_release 22 0–31 continuous
/chroma_2/env_1b_attack 78 0–31 continuous
/chroma_2/env_1b_decay 80 0–31 continuous
/chroma_2/env_1b_release 82 0–31 continuous
/chroma_2/env_2a_attack 25 0–31 continuous
/chroma_2/env_2a_decay 27 0–31 continuous
/chroma_2/env_2a_release 29 0–31 continuous
/chroma_2/env_2b_attack 85 0–31 continuous
/chroma_2/env_2b_decay 87 0–31 continuous
/chroma_2/env_2b_release 89 0–31 continuous
/chroma_2/sweep_shape 15 0–127 continuous
/chroma_2/sweep_shape 75 0–127 continuous
/chroma_2/sweep_rate_mod_b 74 0–127 continuous
/chroma_2/env_2a_delay 23 0–31 continuous
/chroma_2/env_2b_delay 83 0–31 continuous
/chroma_2/sweep_a_mode 12 0–127 continuous
/chroma_2/sweep_b_mode 72 0–127 continuous

Performance MIDI

Notes, pitch bend and any CC are also available: /chroma_2/note/on <note> <velocity>, /chroma_2/cc/<number> <value>, /chroma_2/pitchbend <0-16383>, /chroma_2/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

Which MIDI CC controls the filter cutoff on the Rhodes Chroma 2?

CC 43 (0–63), named /chroma_2/cutoff in SynthHub's map.

How many parameters of the Rhodes Chroma 2 can be controlled over MIDI?

SynthHub's map of the Rhodes Chroma 2 lists 158 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 Rhodes Chroma 2?

Yes: SynthHub's hosted MCP server knows the Rhodes Chroma 2's MIDI map, and its browser relay lets the agent send it parameter changes or load a sound, each sound change confirmed by you.