dsp-thomann/dsp408-protocol.md

DSP 408 Protocol Documentation

TODO

• Existing but not implemented commands: 0x19, 0x25, 0x28, 0x2E, 0x50, 0x51, 0x52, 0x53
• Commands 0x2E, 0x50, 0x51, 0x52, 0x53 seem to be used for firmware update: DO NOT SEND THEM WITHOUT KNOWLEDGE - RISK OF DEVICE BRICK (I brick my device)
• Commands: 0x19, 0x24, 0x28 are triggered by upload preset
• Identify: 0x2C parameters
• Implement: if 2 DSP with same ip, they need to share same socket since dsp dont accept multiples connections
• In unlock check if first byte is device id
• Dsp and python code allow to send commands even if dsp is locked
• Convert back data as in 0x38 to display real value

Tables of Content

Encoding Index

Encoding	Used by	Description
Preset Name	Preset save/load	14-byte fixed string
Channel Name	Channel labeling	8-byte fixed string
Password	Login/lock	4-byte fixed string
Preset Index	Preset select	1-byte index (21 presets)
Channel Index	Gain, Mute, Delay, PEQ, GEQ	1-byte index (12 channels)
PEQ Band Index	PEQ	1-byte index (9 bands)
Frequency Band Index	GEQ	1-byte index (31 bands)
Delay Unit	Channel Delay	1-byte unit selector
Compressor Ratio	Compressor	1-byte index (16 ratios)
Input Source Type	Input select	1-byte index (4 sources)
PEQ Filter Type	PEQ	1-byte index (9 filter types)
Crossover Slope	Crossover	1-byte index (21 slopes)
Matrix Input Mask	Input routing	1-byte bitmask
Channel Gain	Gain	16-bit dB value (-60 to +12 dB)
GEQ / PEQ Gain	GEQ, PEQ	8-bit ±12 dB value
PEQ Q Factor	PEQ	8-bit logarithmic Q value
Hold	Gate	16-bit ms value
Attack	Compressor	16-bit ms value
Release	Compressor	16-bit ms value
Knee	Compressor	8-bit dB value
Sidechain Frequency	Compressor	16-bit logarithmic Hz value
Gate Threshold	Gate	16-bit dB value
Compressor Threshold	Compressor	8-bit dB value
Channel Delay	Delay	8-bit linear value
Meter Level	Metering	Float16 level + peak byte

---

Commands Index

Command	Category	Description
0x01 — Acknowledgement	Connection & Session	Signals the device finished loading/processing and is ready
0x02 — Not Implemented	Connection & Session	Signals that the command just sent is invalid/unimplemented
0x10 — Start	Connection & Session	Initiates a session with the device
0x11 — Disconnect	Connection & Session	Terminates the session
0x12 — Acknowledgement (Client → Device)	Connection & Session	Client-side confirmation after loading parameters
0x13 — Device Name	Device Info	Reads the device's display name
0x14 — Current Preset Index	Preset Management	Reads the currently active preset
0x15 — Set Delay Unit	Channel Processing	Changes the display unit used for delay values
0x20 — Recall Preset	Preset Management	Recalls (loads) a stored preset
0x21 — Store Preset	Preset Management	Saves the current live settings into a preset slot
0x22 — Get Preset Modification Status	Preset Management	Reports which presets have unsaved/modified state
0x23 — Factory Reset	Preset Management	Restores factory defaults
0x27 / 0x24 — Config Chunk (Request / Response)	Preset Management	Streams the full device configuration in indexed chunks
0x26 — Store Preset Name	Preset Management	Sets the working preset name prior to saving
0x29 — Get Preset Name	Preset Management	Reads the name of a given preset
0x2A — Copy Channel	Channel Configuration	Copies one channel's settings onto another
0x2C — Device Flags	Device Info	Reads device status flags, including lock state
0x2D — Unlock Device	Security	Authenticates with a password to unlock the device
0x2F — Lock Device	Security	Locks the device behind a password
0x30 — Set Compressor	Dynamics	Sets compressor parameters for a channel
0x31 — Set Low-Pass Filter	Filters & EQ	Sets the low-pass filter for a channel
0x32 — Set High-Pass Filter	Filters & EQ	Sets the high-pass filter for a channel
0x33 — Set PEQ Band	Filters & EQ	Sets one parametric EQ band (input channels only)
0x34 — Set Gain	Channel Processing	Sets a channel's gain
0x35 — Set Mute	Channel Processing	Mutes or unmutes a channel
0x36 — Invert Gain	Channel Processing	Inverts polarity on a channel
0x38 — Set Delay	Channel Processing	Sets a channel's delay value
0x39 — Set Input Source	Input & Routing	Selects the analog/test signal source
0x3A — Matrix Routing	Input & Routing	Sets which inputs feed a given output channel
0x3B — Link Channel	Channel Configuration	Groups channels so they move together
0x3C — Bypass EQ	Channel Processing	Enables or bypasses all EQ processing on a channel
0x3D — Set Channel Name	Channel Configuration	Sets the display name of an output channel
0x3E — Set Gate Parameters	Dynamics	Sets noise-gate parameters for a channel
0x3F — Set Output Limiter	Dynamics	Sets output-limiter parameters (output channels only)
0x40 — Get Level Meters	Metering	Reads current level-meter and clip-indicator values for all channels
0x41 — Set Matrix Gain	Input & Routing	Sets the send gain from one input to one output
0x48 — Set GEQ Band	Filters & EQ	Sets one band of a 31-band graphic EQ (input channels only)
0x49 — Set GEQ Bypass	Filters & EQ	Enables or bypasses the graphic EQ on an input channel (input channels only)

---

Encoding / Decoding Specification

1. Overview & Conventions

• All multi-byte numeric fields are little-endian: the low-order byte (LO) is transmitted/stored first, the high-order byte (HI) second.

  LO = raw & 0xFF
  HI = (raw >> 8) & 0xFF
  

  raw = LO | (HI << 8)
  

• Quantized parameters (e.g. gain, threshold) are rounded to the nearest valid step before encoding. The decoding formula always reverses the encoding formula exactly.
• All lookup-table fields (enums, indices) are 1 byte unless otherwise noted.

---

2. Fixed-Length Strings

All string fields share one encoding model: write the text as ASCII bytes, then pad up to the fixed length with a pad byte. Decoding reverses this: read the fixed length, then strip trailing pad bytes.

2.1 Preset Name

Field	Value
Purpose	Human-readable preset name
Size	14 bytes
Pad byte	0x20 (space)

Encoding (value → raw):

bytes = ASCII(name)[0:14]
bytes = bytes + 0x20 × (14 - len(bytes))

Decoding (raw → value):

name = ASCII(bytes).rstrip(0x20)

2.2 Channel Name

Field	Value
Purpose	Human-readable channel name
Size	8 bytes
Pad byte	0x00

Encoding (value → raw):

bytes = ASCII(name)[0:8]
bytes = bytes + 0x00 × (8 - len(bytes))

Decoding (raw → value):

name = ASCII(bytes).rstrip(0x00)

2.3 Password

Field	Value
Purpose	Password value
Size	4 bytes
Pad byte	0x00

Encoding (value → raw):

bytes = ASCII(password)[0:4]
bytes = bytes + 0x00 × (4 - len(bytes))

Decoding (raw → value):

password = ASCII(bytes).rstrip(0x00)

---

3. Enumerated & Index Values

All fields in this section are 1 byte and work as a direct lookup table.

Encoding (value → raw): find the desired option in the table and use its byte value. Decoding (raw → value): look up the byte value in the table to get the option.

3.1 Preset Index

Range: 0x00–0x14 (21 presets)

Index	Preset
0x00	Preset 0
0x01	Preset 1
…	…
0x14	Preset 20

3.2 Channel Index

Range: 0x00–0x0B (12 channels)

Index	Channel	Index	Channel
0x00	IN_A	0x06	OUT_3
0x01	IN_B	0x07	OUT_4
0x02	IN_C	0x08	OUT_5
0x03	IN_D	0x09	OUT_6
0x04	OUT_1	0x0A	OUT_7
0x05	OUT_2	0x0B	OUT_8

3.3 PEQ Band Index

Range: 0x00–0x08 (9 bands)

Band limit by channel type:

Channel Type	Maximum Band
Input	B7 (0x07)
Output	B8 (0x08)

Index	Band	Index	Band
0x00	B0	0x05	B5
0x01	B1	0x06	B6
0x02	B2	0x07	B7
0x03	B3	0x08	B8
0x04	B4

3.4 Frequency Band Index

Range: 0x00–0x1E (31 bands, ISO 1/3-octave centers)

Index	Frequency	Index	Frequency	Index	Frequency	Index	Frequency
0x00	20 Hz	0x08	125 Hz	0x10	800 Hz	0x18	5 kHz
0x01	25 Hz	0x09	160 Hz	0x11	1 kHz	0x19	6.3 kHz
0x02	31.5 Hz	0x0A	200 Hz	0x12	1.25 kHz	0x1A	8 kHz
0x03	40 Hz	0x0B	250 Hz	0x13	1.6 kHz	0x1B	10 kHz
0x04	50 Hz	0x0C	315 Hz	0x14	2 kHz	0x1C	12.5 kHz
0x05	63 Hz	0x0D	400 Hz	0x15	2.5 kHz	0x1D	16 kHz
0x06	80 Hz	0x0E	500 Hz	0x16	3.15 kHz	0x1E	20 kHz
0x07	100 Hz	0x0F	630 Hz	0x17	4 kHz

3.6 Compressor Ratio

Range: 0x0000–0x0F00 (16 values)

Value	Ratio	Value	Ratio
0x0000	1:1	0x0800	3.5:1
0x0100	1.1:1	0x0900	4:1
0x0200	1.3:1	0x0A00	5:1
0x0300	1.5:1	0x0B00	6:1
0x0400	1.7:1	0x000C	8:1
0x0500	2:1	0x0D00	10:1
0x0600	2.5:1	0x0E00	20:1
0x0700	3:1	0x0F00	LIMIT

3.7 Input Source Type

Range: 0x00–0x03 (4 types)

Value	Input Source
0x00	Analog
0x01	Pink Noise
0x02	White Noise
0x03	Sine Wave

3.8 PEQ Filter Type

Range: 0x00–0x08 (9 types)

Value	Filter	Value	Filter
0x00	Peak	0x05	HP 6dB
0x01	Low Shelf	0x06	HP 12dB
0x02	High Shelf	0x07	All Pass 1
0x03	LP 6dB	0x08	All Pass 2
0x04	LP 12dB

3.9 Crossover Slope

Range: 0x00–0x14 (21 values)

Value	Slope	Value	Slope
0x00	Bypass	0x0B	BW 30
0x01	BW 6	0x0C	BL 30
0x02	BL 6	0x0D	BW 36
0x03	BW 12	0x0E	BL 36
0x04	BL 12	0x0F	LR 36
0x05	LR 12	0x10	BW 42
0x06	BW 18	0x11	BL 42
0x07	BL 18	0x12	BW 48
0x08	BW 24	0x13	BL 48
0x09	BL 24	0x14	LR 48
0x0A	LR 24

---

4. Bit Mask Values

4.1 Matrix Input Mask

Field	Value
Purpose	Which inputs are active/routed
Size	1 byte
Range	0x00–0x0F

Input	Bit mask
IN_A	0x01
IN_B	0x02
IN_C	0x04
IN_D	0x08

Encoding (value → raw): OR together the bit mask of every active input.

raw = (IN_A ? 0x01 : 0) | (IN_B ? 0x02 : 0) | (IN_C ? 0x04 : 0) | (IN_D ? 0x08 : 0)

Decoding (raw → value): AND the raw byte with each bit mask to test whether that input is active.

IN_A_active = (raw & 0x01) != 0
IN_B_active = (raw & 0x02) != 0
IN_C_active = (raw & 0x04) != 0
IN_D_active = (raw & 0x08) != 0

---

5. Gain & Equalizer Parameters

5.1 Channel Gain

Field	Value
Purpose	Per-channel input/output gain
Size	2 bytes, little-endian
Range	-60 dB to +12 dB

Quantization:

dB Range	Resolution
[-60, -20)	0.5 dB
[-20, +12]	0.1 dB

Encoding (value → raw):

if -60 <= dB < -20:
    raw = round((dB + 60) / 0.5)
if -20 <= dB <= 12:
    raw = round(80 + (dB + 20) / 0.1)

LO = raw & 0xFF
HI = (raw >> 8) & 0xFF

Decoding (raw → value):

raw = LO | (HI << 8)

if 0 <= raw <= 79:
    dB = raw × 0.5 - 60
if 80 <= raw <= 320:
    dB = (raw - 80) × 0.1 - 20

5.2 GEQ / PEQ Gain

Field	Value
Purpose	Graphic/parametric EQ band gain
Size	2 bytes
Range	-12 dB to +12 dB
Resolution	0.1 dB

Encoding (value → raw):

raw = round(dB × 10 + 120)
LO = raw & 0xFF
HI = (raw >> 8) & 0xFF

Decoding (raw → value):

dB = (raw - 120) / 10

Raw	Gain
0x00	-12 dB
0x78	0 dB
0xF0	+12 dB

5.3 PEQ Q Factor

Field	Value
Purpose	Parametric EQ bandwidth (Q)
Size	1 byte, logarithmic index
Range	0.40 to 128.00
Raw range	0x00–0x64 (0–100)

Encoding (value → raw):

raw = round(log(Q / 0.40) / log(128 / 0.40) × 100)

Decoding (raw → value):

Q = 0.40 × (128 / 0.40) ^ (raw / 100)

---

6. Dynamics Processing Parameters

6.1 Hold (Gate)

Field	Value
Purpose	Gate hold time
Size	2 bytes, little-endian
Range	10 ms to 999 ms

Encoding (value → raw):

raw = hold_ms - 1
LO = raw & 0xFF
HI = (raw >> 8) & 0xFF

Decoding (raw → value):

raw = LO | (HI << 8)
hold_ms = raw + 1

6.2 Attack (Compressor)

Field	Value
Purpose	Compressor attack time
Size	2 bytes, little-endian
Range	1 ms to 999 ms

Encoding (value → raw):

raw = attack_ms - 1
LO = raw & 0xFF
HI = (raw >> 8) & 0xFF

Decoding (raw → value):

raw = LO | (HI << 8)
attack_ms = raw + 1

6.3 Release

Field	Value
Purpose	Release time
Size	2 bytes, little-endian
Range	10 ms to 3000 ms

Encoding (value → raw):

raw = release_ms - 1
LO = raw & 0xFF
HI = (raw >> 8) & 0xFF

Decoding (raw → value):

raw = LO | (HI << 8)
release_ms = raw + 1

6.4 Knee (Compressor)

Field	Value
Purpose	Compressor knee width
Size	2 bytes
Range	0 dB to 12 dB
Resolution	1 dB

Encoding (value → raw):

raw = round(knee_db)
LO = raw & 0xFF
HI = (raw >> 8) & 0xFF

Decoding (raw → value):

knee_db = LO | (HI << 8)

6.5 Sidechain Frequency (Compressor)

Field	Value
Purpose	Compressor sidechain filter frequency
Size	2 bytes, little-endian
Range	19.70 Hz to 20160 Hz
Raw range	0x0000–0x012C

Encoding (value → raw):

raw = round(log(Hz / 19.70) / log(20160 / 19.70) × 300)
LO = raw & 0xFF
HI = (raw >> 8) & 0xFF

Decoding (raw → value):

raw = LO | (HI << 8)
Hz = 19.70 × (20160 / 19.70) ^ (raw / 300)

6.6 Gate Threshold Encoding

Gate threshold uses a 16-bit little-endian value.

Field	Value
Purpose	Gate open/close threshold
Size	2 bytes, little-endian
Range	-90.0 dB to 0.0 dB
Raw range	0x0000–0x00B4 (0–180)
Resolution	0.5 dB

Encoding (dB → raw):

raw = round((dB - (-90.0)) × 2)

LO = raw & 0xFF
HI = (raw >> 8) & 0xFF

Decoding (raw → dB):

raw = LO | (HI << 8)
dB = -90.0 + (raw / 2)

6.7 Compressor Threshold

Field	Value
Purpose	Compressor threshold
Size	2 bytes
Range	-110 dB to 0 dB
Resolution	0.5 dB

Encoding (value → raw):

raw = round((dB - (-110)) × 2)
LO = raw & 0xFF
HI = (raw >> 8) & 0xFF

Decoding (raw → value):

raw = LO | (HI << 8)
dB = (raw / 2) - 110

---

7. Delay

7.1 Channel Delay

Field	Value
Purpose	Per-channel delay
Size	1 byte
Raw range	0x00–0xFF (0–255)

Range by selected unit (see Delay Unit):

Unit	delay_min	delay_max
Millisecond	0.000 ms	680.000 ms
Meter	0.000 m	233.580 m
Feet	0.000 ft	766.329 ft

Encoding (value → raw):

raw = round((delay - delay_min) / (delay_max - delay_min) × 255)

Decoding (raw → value):

delay = delay_min + (raw / 255) × (delay_max - delay_min)

7.2 Delay Unit

Range: 0x00–0x02 (3 units)

Value	Unit
0x00	Millisecond
0x01	Meter
0x02	Feet

---

8. Metering

8.1 Meter Level

Field	Value
Purpose	Per-channel level + peak metering
Size	3 bytes per channel
Total	12 channels × 3 bytes = 36 bytes

Byte offset	Field	Format
0–1	Level	IEEE754 float16, little-endian
2	Peak	1-byte peak value (format not specified in source)

Encoding (value → raw):

level_bytes = float16_encode(level)   // 2 bytes, little-endian
peak_byte   = peak_encode(peak)       // format undefined — see note below
raw = level_bytes + peak_byte

Decoding (raw → value):

level = float16_decode(raw[0:2])      // little-endian
peak  = peak_decode(raw[2])           // format undefined — see note below

---

Command Specification

1. Frame Structure

Every command — query or response — shares one frame layout. Colors match the highlighted examples throughout this document:

Field	Size	Color	Description
STX	2 bytes	■	Fixed start marker: 10 02
DIR	2 bytes	■	Direction (see below)
LEN	1 byte	■	Byte count of CMD + DATA
CMD	1 byte	■	Command code
DATA	LEN - 1 bytes	■	Command payload (may be 0 bytes)
ETX	2 bytes	■	Fixed end marker: 10 03
CS	1 byte	■	Checksum (see below)

Example skeleton:

10 02 DIR DIR LEN CMD DATA... 10 03 CS

Direction (DIR)

Value	Direction
00 XX	Host → Device (Query)
XX 00	Device → Host (Response)

XX represents the device Id

Length (LEN)

LEN = size(CMD) + size(DATA) = 1 + size(DATA)

Checksum (CS)

The checksum is the XOR of every byte in the frame from DIR through DATA, inclusive, with an initial seed of 0x01.

Encoding (value → raw):

CS = DIR[0] ^ DIR[1] ^ LEN ^ CMD ^ DATA[0] ^ ... ^ DATA[N-1] ^ 0x01

Decoding / verification (raw → check):

computed_CS = DIR[0] ^ DIR[1] ^ LEN ^ CMD ^ DATA[0] ^ ... ^ DATA[N-1] ^ 0x01
valid = (computed_CS == received_CS)

---

2. Command Template

Every command in this document uses the same shape:

0xXX — Name
Direction: Host→Device / Device→Host / Both
Category: ...
Purpose: one-line description
Sequencing: what must precede/follow this command, if anything
Payload Fields — table of Offset | Field | Size | Encoding Reference | Value/Range
Example — annotated, color-coded hex frame

---

3. Connection & Session

0x01 — Acknowledgement

Direction: Device → Host
Category: Connection & Session
Purpose: Signals the device finished loading/processing and is ready.
Sequencing: Sent after any state-changing command.

Payload Fields

Offset	Field	Size	Encoding
—	(none)	0 bytes	Command has no payload

Example

10 02 01 00 01 01 10 03 00

---

0x02 — Not Implemented

Direction: Device → Host
Category: Connection & Session
Purpose: Signals that the command just sent is invalid/unimplemented.
Sequencing: Sent in place of 0x01 when a command fails to parse or is unsupported.

Payload Fields

Offset	Field	Size	Encoding
—	(none)	0 bytes	Command has no payload

Example

10 02 01 00 01 02 10 03 00

---

0x10 — Start

Direction: Host → Device (Query), Device → Host (Response)
Category: Connection & Session
Purpose: Initiates a session with the device.
Sequencing: First command sent on connect.

Payload Fields (Response only)

Offset	Field	Size	Encoding
Byte 1	Status	1 byte	0x13 = OK

Example — Query

10 02 00 01 01 10 10 03 11

Example — Response

10 02 01 00 02 10 13 10 03 01

---

0x11 — Disconnect

Direction: Host → Device
Category: Connection & Session
Purpose: Terminates the session.

Payload Fields

Offset	Field	Size	Encoding
—	(none)	0 bytes	Command has no payload

Example

10 02 00 01 01 11 10 03 10

---

0x12 — Acknowledgement (Client → Device)

Direction: Host → Device
Category: Connection & Session
Purpose: Client-side confirmation after loading parameters (mirrors 0x01 but in the opposite direction).
Sequencing: Followed by 0x01.

Payload Fields

Offset	Field	Size	Encoding
—	(none)	0 bytes	Command has no payload

Example

10 02 00 01 01 12 10 03 13

---

4. Device Info

0x13 — Device Name

Direction: Host → Device (Query), Device → Host (Response)
Category: Device Info
Purpose: Reads the device's display name.

Payload Fields (Response only)

Offset	Field	Size	Encoding
Byte 1 – Byte N-1	Device name	13 bytes	Enc §2.2 Channel Name

Example — Query

10 02 00 01 01 13 10 03 12

Example — Response

10 02 01 00 0E 13 44 53 50 34 30 38 20 56 30 31 30 34 50 10 03 45

---

0x2C — Device Flags

Direction: Host → Device (Query), Device → Host (Response)
Category: Device Info
Purpose: Reads device status flags, including lock state. Not fully reverse-engineered.

Payload Fields (Response only)

Offset	Field	Size	Encoding
Byte 1	Unknown	1 byte	00 observed
Byte 2-3	Unknown	2 bytes	27 0F observed
Byte 4-5	Unknown	2 bytes	00 00 observed
Byte 6	Lock state	1 byte	01 = Locked, 00 = Unlocked

Example — Query

10 02 00 01 01 2C 10 03 2D

Example — Response

10 02 01 00 07 2C 00 27 0F 00 00 00 10 03 03

---

5. Preset Management

0x14 — Current Preset Index

Direction: Host → Device (Query), Device → Host (Response)
Category: Preset Management
Purpose: Reads the currently active preset.

Payload Fields (Response only)

Offset	Field	Size	Encoding
Byte 1	Preset index	1 byte	Enc §3.1 Preset Index

Example — Query

10 02 00 01 01 14 10 03 15

Example — Response

10 02 01 00 02 14 06 10 03 10

---

0x20 — Recall Preset

Direction: Host → Device
Category: Preset Management
Purpose: Recalls (loads) a stored preset.
Sequencing: Followed by 0x01 (Acknowledgement) once loading finishes.

Payload Fields

Offset	Field	Size	Encoding
Byte 1	Preset index	1 byte	Enc §3.1 Preset Index

Example

10 02 00 01 02 20 10 10 03 32

---

0x21 — Store Preset

Direction: Host → Device
Category: Preset Management
Purpose: Saves the current live settings into a preset slot.
Sequencing: Call 0x26 (Store Preset Name) first to set the name being saved. Must be followed by 0x12.

Payload Fields

Offset	Field	Size	Encoding
Byte 1	Preset slot	1 byte	Enc §3.1 Preset Index, no 0x00

Example

10 02 00 01 02 21 01 10 03 CS

---

0x22 — Get Preset Modification Status

Direction: Host → Device (Query), Device → Host (Response)
Category: Preset Management
Purpose: Reports which presets have unsaved/modified state.

Payload Fields (Response only)

Offset	Field	Size	Encoding
Byte 1–Byte 20	Per-preset modified flag	1 byte each	0xFF = modified, 0x00 = unmodified

Example — Query

10 02 00 01 01 22 10 03 23

Example — Response

10 02 01 00 15 22 FF 00 FF FF FF 00 00 00 00 00 00 00 00 00 00 00 00 00 00 10 03 37

---

0x23 — Factory Reset

Direction: Host → Device
Category: Preset Management
Purpose: Restores factory defaults.
Sequencing: Device acknowledges with 0x01.

Payload Fields

Offset	Field	Size	Encoding
—	(none)	0 bytes	Command has no payload

Example

10 02 00 01 01 23 10 03 CS

---

0x27 / 0x24 — Config Chunk (Request / Response)

Direction: 0x27 Host→Device (Request), 0x24 Device→Host (Response)
Category: Preset Management
Purpose: Streams the full device configuration in indexed chunks.
Sequencing: Request 0x27 is followed by response 0x24. Must be followed by 0x12, after full batch request.

Payload Fields — Request (0x27)

Offset	Field	Size	Encoding
Byte 1	Chunk index	1 byte	0x00–0x1C

Payload Fields — Response (0x24)

Offset	Field	Size	Encoding
Byte 1	Sub-index	1 bytes	0x00–0x1C
Byte 2–Byte 51	Configuration data	50 bytes	binary/ASCII mixed

Example — Request

10 02 00 01 03 27 INDEX 10 03 CS

Example — Response

10 02 01 00 34 24 00 FF 00 44 65 66 61 75 6C 74 20 50 72 65 73 65 74 49 6E 41 00 00 00 00 00 00 00 63 00 63 00 00 00 78 00 78 00 78 00 78 00 78 00 78 00 78 00 78 00 10 03 BF

---

Config Data — Reassembled Payload Layout

The 50-byte pages from chunks 0x00–0x1C are concatenated in index order into a single buffer before parsing. Below is that buffer's field layout, byte-for-byte, in the order fields are consumed.

Legend (protocol constants used below)

Symbol	Meaning
PNL	PRESET_NAME_LENGTH
CNL	CHANNEL_NAME_LENGTH
N_IN	number of input channels (len(INPUT_ORDER))
N_OUT	number of output channels (len(OUTPUT_ORDER))
N_FREQ	number of GEQ bands (len(list(FrequencyValue)))
N_PEQ_IN	number of input PEQ bands (len(PEQ_INPUT_BANDS))
N_PEQ_OUT	number of output PEQ bands (len(PEQ_OUTPUT_BANDS))

Header

Offset	Field	Size	Encoding
0x00	Flags (unused)	2 bytes	reserved
0x02	Preset name	PNL bytes	ASCII, raw → raw_to_preset_name

Per Input Channel — repeats N_IN times

Offset (within block)	Field	Size	Encoding
+0x00	Channel name	CNL bytes	ASCII, raw → raw_to_channel_name
+CNL	Gate: attack	2 bytes	u16 → raw_to_attack_ms
+CNL+2	Gate: release	2 bytes	u16 → raw_to_release_ms
+CNL+4	Gate: hold	2 bytes	u16 → raw_to_hold_ms
+CNL+6	Gate: threshold	2 bytes	u16 → raw_to_threshold_db
+CNL+8	GEQ gains	2 × N_FREQ bytes	N_FREQ × u16 → raw_to_eq_gain
+CNL+8+2·N_FREQ	PEQ chain	6 × N_PEQ_IN bytes	N_PEQ_IN bands, each: u16 gain, u16 freq, u8 Q, u8 filter type
…	Crossover: HP freq	2 bytes	u16 → raw_to_frequency_hz
…	Crossover: LP freq	2 bytes	u16 → raw_to_frequency_hz
…	Crossover: HP slope	1 byte	u8 → raw_to_crossover_filter
…	Crossover: LP slope	1 byte	u8 → raw_to_crossover_filter
…	Channel gain	2 bytes	u16 → raw_to_channel_gain
…	Phase inverted	1 byte	u8 bool
…	Reserved	2 bytes	skipped
…	Delay (raw)	1 byte	u8, resolved via raw_to_delay(value, delay_unit) once the header-level delay unit is parsed
…	Linked channels	2 bytes	u16 bitmap → raw_to_link_channels

Per-channel block size: CNL + 2·N_FREQ + 6·N_PEQ_IN + 22 bytes.

Per Output Channel — repeats N_OUT times (immediately follows the last input channel block)

Offset (within block)	Field	Size	Encoding
+0x00	Channel name	CNL bytes	ASCII, raw → raw_to_channel_name
…	Matrix: connected	2 bytes	u16 bitmap → raw_to_matrix
…	Matrix: gains	8 bytes	4 × u16 → raw_to_matrix_gain
…	Crossover (HP/LP freq + slope)	6 bytes	same layout as input crossover
…	PEQ chain	6 × N_PEQ_OUT bytes	N_PEQ_OUT bands, same per-band layout as input
…	Compressor: ratio	2 bytes	u16 → raw_to_ratio
…	Compressor: attack	2 bytes	u16 → raw_to_attack_ms
…	Compressor: release	2 bytes	u16 → raw_to_release_ms
…	Compressor: knee	2 bytes	u16 → raw_to_knee_db
…	Compressor: threshold	2 bytes	u16 → raw_to_threshold_db
…	Limiter: attack	2 bytes	u16 → raw_to_attack_ms
…	Limiter: release	2 bytes	u16 → raw_to_release_ms
…	Reserved	2 bytes	skipped
…	Limiter: threshold	2 bytes	u16 → raw_to_threshold_db
…	Channel gain	2 bytes	u16 → raw_to_channel_gain
…	Phase inverted	1 byte	u8 bool
…	Reserved	2 bytes	skipped
…	Delay (raw)	1 byte	u8, resolved via raw_to_delay(value, delay_unit)
…	Linked channels	2 bytes	u16 bitmap → raw_to_link_channels

Per-channel block size: CNL + 6·N_PEQ_OUT + 42 bytes.

Global Flags (immediately follows the last output channel block)

Offset (within section)	Field	Size	Encoding
+0x00	Input mute bitmap	2 bytes	u16, bit i = INPUT_ORDER[i] muted
+0x02	Output mute bitmap	2 bytes	u16, bit i = OUTPUT_ORDER[i] muted
+0x04	Input PEQ band mute	2 × N_IN bytes	one u16 per input channel, bit j = PEQ_INPUT_BANDS[j] bypassed
+0x04+2·N_IN	Output PEQ band mute	2 × N_OUT bytes	one u16 per output channel, bit j = PEQ_OUTPUT_BANDS[j] bypassed

Input Source & Delay Unit (immediately follows Global Flags)

Offset (within section)	Field	Size	Encoding
+0x00	Input source type	2 bytes	u16 → raw_to_input_source
+0x02	Input source frequency	2 bytes	u16 → raw_to_frequency_value
+0x04	Delay unit	2 bytes	u16 → raw_to_delay_unit (applies to all previously-read raw delay bytes)

Trailing Bypass Flags (immediately follows Input Source & Delay Unit)

Offset (within section)	Field	Size	Encoding
+0x00	Input PEQ chain bypass bitmap	2 bytes	u16, bit i = INPUT_ORDER[i]'s PEQ chain bypassed
+0x02	Output PEQ chain bypass bitmap	2 bytes	u16, bit i = OUTPUT_ORDER[i]'s PEQ chain bypassed
+0x04	Input GEQ bypass bitmap	2 bytes	u16, bit i = INPUT_ORDER[i]'s GEQ bypassed

Total reassembled payload size: 2 + PNL + N_IN·(CNL + 2·N_FREQ + 6·N_PEQ_IN + 22) + N_OUT·(CNL + 6·N_PEQ_OUT + 42) + 4 + 2·N_IN + 2·N_OUT + 4 + 2 + 6 bytes.

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0x26 — Store Preset Name

Direction: Host → Device
Category: Preset Management
Purpose: Sets the working preset name prior to saving.
Sequencing: Call before 0x21 (Store Preset).

Payload Fields

Offset	Field	Size	Encoding
Byte 1–Byte 14	Preset name	14 bytes	Enc §2.1 Preset Name

Example

10 02 00 01 0F 26 50 72 65 73 65 74 20 4E 61 6D 65 20 20 20 10 03 CS

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0x29 — Get Preset Name

Direction: Host → Device (Query), Device → Host (Response)
Category: Preset Management
Purpose: Reads the name of a given preset.

Payload Fields — Query

Offset	Field	Size	Encoding
Byte 1	Preset index	1 byte	Enc §3.1 Preset Index

Payload Fields — Response

Offset	Field	Size	Encoding
Byte 1–Byte N	Preset name	14 bytes	Enc §2.1 Preset Name

Example — Query

10 02 00 01 02 29 00 10 03 2B

Example — Response

10 02 01 00 10 29 4D 61 69 6E 20 70 72 65 73 65 74 20 20 20 10 03 17

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6. Security

0x2D — Unlock Device

Direction: Host → Device (Query), Device → Host (Response)
Category: Security
Purpose: Authenticates with a password to unlock the device.

Payload Fields — Query

Offset	Field	Size	Encoding
Byte 1	Unknown	1 byte	00 observed
Byte 2–Byte N	Password	4 bytes	Enc §2.3 Password

Payload Fields — Response

Offset	Field	Size	Encoding
Byte 1	Status category	1 byte	00 observed
Byte 2	Authentication result	1 byte	00 = Failed, 01 = Success

Example — Query (password 1234)

10 02 00 01 06 2D 00 31 32 33 34 10 03 2F

Example — Response

10 02 01 00 03 2D 00 01 10 03 2F

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0x2F — Lock Device

Direction: Host → Device
Category: Security
Purpose: Locks the device behind a password.
Sequencing: Followed by 0x01.

Payload Fields

Offset	Field	Size	Encoding
Byte 1–Byte N	Password	4 bytes	Enc §2.3 Password

Example (password 1234)

10 02 00 01 05 2F 31 32 33 34 10 03 2E

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7. Channel Configuration

0x2A — Copy Channel

Direction: Host → Device
Category: Channel Configuration
Purpose: Copies one channel's settings onto another.
Sequencing: Followed by 0x01.

Payload Fields

Offset	Field	Size	Encoding
Byte 1	Source channel	1 byte	Enc §3.2 Channel Index
Byte 2	Destination channel	1 byte	Enc §3.2 Channel Index

Example

10 02 00 01 03 2A 00 01 10 03 28

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0x3B — Link Channel

Direction: Host → Device
Category: Channel Configuration
Purpose: Groups channels so they move together.
Sequencing: Followed by 0x01. Use 0x2A (Copy Channel) before linking channels with 0x3B.

Payload Fields

Offset	Field	Size	Encoding
Byte 1	Channel index	1 byte	Enc §3.2 Channel Index
Byte 2	Link mask	1 byte	Bitmask — same OR pattern as Enc §4.1 Matrix Input Mask, generalized to the channel's own bit position

Link mask rule: bit N set → channel N is linked to this channel.

Value	Meaning
0x00	No linked channels
0x01–0x0F	Valid range for input channels (bits 0–3 only)
0x01–0xFF	Valid range for output channels (bits 0–7)

Example

10 02 00 01 03 3B 03 08 10 03 33

(Channel 0x03, link mask 0x08 → linked to channel 3)

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0x3D — Set Channel Name

Direction: Host → Device
Category: Channel Configuration
Purpose: Sets the display name of an output channel.
Sequencing: Followed by 0x01.

Payload Fields

Offset	Field	Size	Encoding
Byte 1	Output channel index	1 byte	Enc §3.2 Channel Index
Byte 2–Byte 9	Channel name	8 bytes	Enc §2.2 Channel Name

Example

10 02 00 01 0A 3D CH NAME[8] 10 03 CS

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8. Channel Processing

0x15 — Set Delay Unit

Direction: Host → Device
Category: Channel Processing
Purpose: Changes the display unit used for delay values.
Sequencing: Device acknowledges with 0x01.

Payload Fields

Offset	Field	Size	Encoding
Byte 1	Delay unit	1 byte	Enc §3.5 Delay Unit

Example

10 02 00 01 02 15 01 10 03 CS

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0x34 — Set Gain

Direction: Host → Device
Category: Channel Processing
Purpose: Sets a channel's gain.
Sequencing: Device acknowledges with 0x01.

Payload Fields

Offset	Field	Size	Encoding
Byte 1	Channel index	1 byte	Enc §3.2 Channel Index
Byte 2-3	Gain	2 bytes, little-endian	Enc §5.1 Channel Gain

Example

10 02 00 01 04 34 CH LO HI 10 03 CS

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0x35 — Set Mute

Direction: Host → Device
Category: Channel Processing
Purpose: Mutes or unmutes a channel.
Sequencing: Device acknowledges with 0x01.

Payload Fields

Offset	Field	Size	Encoding
Byte 1	Channel index	1 byte	Enc §3.2 Channel Index
Byte 2	Mute state	1 byte	0x00 = Unmuted, 0x01 = Muted

Example

10 02 00 01 03 35 CH MUTE 10 03 CS

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0x36 — Invert Gain

Direction: Host → Device
Category: Channel Processing
Purpose: Inverts polarity on a channel.
Sequencing: Device acknowledges with 0x01.

Payload Fields

Offset	Field	Size	Encoding
Byte 1	Channel index	1 byte	Enc §3.2 Channel Index
Byte 2	Invert state	1 byte	0x00 = Normal, 0x01 = Inverted

Example

10 02 00 01 03 36 CH INVERT 10 03 CS

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0x38 — Set Delay

Direction: Host → Device
Category: Channel Processing
Purpose: Sets a channel's delay value.
Sequencing: Device acknowledges with 0x01.

Payload Fields

Offset	Field	Size	Encoding
Byte 1	Channel index	1 byte	Enc §3.2 Channel Index
Byte 2	Reserved	1 byte	Always 0x00
Byte 3	Delay	1 byte	Enc §7.1 Channel Delay

Example

10 02 00 01 04 38 CH 00 DELAY 10 03 CS

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0x3C — Bypass EQ

Direction: Host → Device
Category: Channel Processing
Purpose: Enables or bypasses all EQ processing on a channel.
Sequencing: Device acknowledges with 0x01.

Payload Fields

Offset	Field	Size	Encoding
Byte 1	Channel index	1 byte	Enc §3.2 Channel Index
Byte 2	EQ bypass state	1 byte	0x00 = Active, 0x01 = Bypassed

Example

10 02 00 01 03 3C CH BYPASS 10 03 CS

---

9. Dynamics

0x30 — Set Compressor

Direction: Host → Device
Category: Dynamics
Purpose: Sets compressor parameters for a channel.
Sequencing: Device acknowledges with 0x01.

Payload Fields

Offset	Field	Size	Encoding
Byte 1	Channel index	1 byte	Enc §3.2 Channel Index
Byte 2-3	Ratio	2 bytes, little-endian	Enc §3.6 Compressor Ratio
Byte 4-5	Attack	2 bytes, little-endian	Enc §6.2 Attack
Byte 6-7	Release	2 bytes, little-endian	Enc §6.3 Release
Byte 8-9	Knee	2 bytes, little-endian	Enc §6.4 Knee
Byte 10-11	Threshold	2 bytes, little-endian	Enc §6.7 Compressor Threshold

Example

10 02 00 01 0C 30 CH RA 00 AT_LO AT_HI RE_LO RE_HI KN 00 TH 00 10 03 CS

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0x3E — Set Gate Parameters

Direction: Host → Device
Category: Dynamics
Purpose: Sets noise-gate parameters for a channel.
Sequencing: Device acknowledges with 0x01.

Payload Fields

Offset	Field	Size	Encoding
Byte 1	Channel index	1 byte	Enc §3.2 Channel Index
Byte 2-3	Attack	2 bytes, little-endian	Enc §6.2 Attack
Byte 4-5	Release	2 bytes, little-endian	Enc §6.3 Release
Byte 6-7	Hold	2 bytes, little-endian	Enc §6.1 Hold
Byte 8-9	Threshold	2 bytes, little-endian	Enc §6.6 Gate Threshold

Example

10 02 00 01 0A 3E CH AT 00 RE_LO RE_HI HO_LO HO_HI GA 00 10 03 82

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0x3F — Set Output Limiter

Direction: Host → Device
Category: Dynamics
Purpose: Sets output-limiter parameters. Output channels only.
Sequencing: Device acknowledges with 0x01.

Payload Fields

Offset	Field	Size	Encoding
Byte 1	Output channel index	1 byte	Enc §3.2 Channel Index
Byte 2-3	Attack	2 bytes, little-endian	Enc §6.2 Attack
Byte 4-5	Release	2 bytes, little-endian	Enc §6.3 Release
Byte 6-7	Reserved	2 bytes	Always 0000
Byte 8-9	Threshold	2 bytes, little-endian	Enc §6.7 Compressor Threshold

Example

10 02 00 01 0A 3F CH AT_LO AT_HI RE_LO RE_HI 00 00 TH 00 10 03 CS

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10. Filters & EQ

0x31 — Set Low-Pass Filter

Direction: Host → Device
Category: Filters & EQ
Purpose: Sets the low-pass filter for a channel.
Sequencing: Device acknowledges with 0x01.

Payload Fields

Offset	Field	Size	Encoding
Byte 1	Channel index	1 byte	Enc §3.2 Channel Index
Byte 2-3	Cutoff frequency	2 bytes, little-endian	Enc §6.5 Sidechain Frequency
Byte 4	Filter type	1 byte	Enc §3.9 Crossover Slope

Example

10 02 00 01 04 31 CH FREQ_LO FREQ_HI TYPE 10 03 CS

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0x32 — Set High-Pass Filter

Direction: Host → Device
Category: Filters & EQ
Purpose: Sets the high-pass filter for a channel.
Sequencing: Device acknowledges with 0x01.

Payload Fields

Offset	Field	Size	Encoding
Byte 1	Channel index	1 byte	Enc §3.2 Channel Index
Byte 2-3	Cutoff frequency	2 bytes, little-endian	Enc §6.5 Sidechain Frequency
Byte 4	Filter type	1 byte	Enc §3.9 Crossover Slope

Example

10 02 00 01 04 32 CH FREQ_LO FREQ_HI TYPE 10 03 CS

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0x33 — Set PEQ Band

Direction: Host → Device
Category: Filters & EQ
Purpose: Sets one parametric EQ band. Input channels only.
Sequencing: Device acknowledges with 0x01.

Payload Fields

Offset	Field	Size	Encoding
Byte 1	Channel index	1 byte	Enc §3.2 Channel Index
Byte 2	PEQ band index	1 byte	Enc §3.3 PEQ Band Index
Byte 3-4	Gain	2 bytes, little-endian	Enc §5.2 GEQ/PEQ Gain
Byte 5-6	Frequency	2 bytes, little-endian	Enc §6.5 Sidechain Frequency
Byte 7	Q factor	1 byte	Enc §5.3 PEQ Q Factor
Byte 8	Filter type	1 byte	Enc §3.8 PEQ Filter Type
Byte 9	Bypass	1 byte	0x00 = Enabled, 0x01 = Bypassed

Example

10 02 00 01 0A 33 CH BAND GAIN 00 FREQ_LO FREQ_HI Q TYPE BYPASS 10 03 CS

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0x48 — Set GEQ Band

Direction: Host → Device
Category: Filters & EQ
Purpose: Sets one band of a 31-band graphic EQ. Input channels only.
Sequencing: Device acknowledges with 0x01.

Payload Fields

Offset	Field	Size	Encoding
Byte 1	Channel index	1 byte	Enc §3.2 Channel Index
Byte 2	GEQ band index	1 byte	Enc §3.4 Frequency Band Index
Byte 3-4	Gain	2 bytes, little-endian	Enc §5.2 GEQ/PEQ Gain

Example

10 02 00 01 05 48 CH BAND DB 00 10 03 CS

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0x49 — Set GEQ Bypass

Direction: Host → Device
Category: Filters & EQ
Purpose: Enables or bypasses the graphic EQ on an input channel.
Sequencing: Device acknowledges with 0x01.

Payload Fields

Offset	Field	Size	Encoding
Byte 1	Channel index	1 byte	Enc §3.2 Channel Index
Byte 2	Bypass	1 byte	0x00 = GEQ enabled, 0x01 = GEQ bypassed

Example

10 02 00 01 02 49 CH BP 10 03 CS

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11. Input & Routing

0x39 — Set Input Source

Direction: Host → Device
Category: Input & Routing
Purpose: Selects the analog/test signal source.
Sequencing: Device acknowledges with 0x01.

Payload Fields

Offset	Field	Size	Encoding
Byte 1	Source type	1 byte	Enc §3.7 Input Source Type
Byte 2	Sine wave frequency (only meaningful when Byte 1 = 0x03)	1 byte	Enc §3.4 Frequency Band Index

Examples

Analog: 10 02 00 01 03 39 00 00 10 03 3A

Pink Noise: 10 02 00 01 03 39 01 00 10 03 3B

White Noise: 10 02 00 01 03 39 02 00 10 03 38

Sine Wave: 10 02 00 01 03 39 03 XX 10 03 YY

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0x3A — Matrix Routing

Direction: Host → Device
Category: Input & Routing
Purpose: Sets which inputs feed a given output channel.
Sequencing: Device acknowledges with 0x01.

Payload Fields

Offset	Field	Size	Encoding
Byte 1	Output channel	1 byte	Enc §3.2 Channel Index
Byte 2	Input routing mask	1 byte	Enc §4.1 Matrix Input Mask

Example

10 02 00 01 03 3A OUT INPUT_MASK 10 03 CS

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0x41 — Set Matrix Gain

Direction: Host → Device
Category: Input & Routing
Purpose: Sets the send gain from one input to one output.
Sequencing: Device acknowledges with 0x01.

Payload Fields

Offset	Field	Size	Encoding
Byte 1	Output channel index	1 byte	Enc §3.2 Channel Index
Byte 2	Input channel index	1 byte	Enc §3.2 Channel Index
Byte 3-4	Gain	2 bytes, little-endian	Enc §5.1 Channel Gain

Example

10 02 00 01 05 41 CH_OUT CH_IN GAIN_LO GAIN_HI 10 03 CS

---

12. Metering

0x40 — Get Level Meters

Direction: Host → Device (Query), Device → Host (Response)
Category: Metering
Purpose: Reads current level-meter and clip-indicator values for all channels.

Payload Fields (Response only)

Offset	Field	Size	Encoding
Byte 1-36	12 meter channels	3 bytes × 12	Enc §8.1 Meter Level
Byte 37	Input clip indicator	1 byte bitmask	Same OR bitmask pattern as Enc §4.1
Byte 38	Output clip indicator	1 byte bitmask	Same OR bitmask pattern as Enc §4.1

Example — Query

10 02 00 01 01 40 10 03 41

Example — Response

10 02 01 00 27 40 A2 36 A5 A0 36 A0 ... 39 00 00 10 03 75

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