Helix M ONE X – Compact Class D Mono Subwoofer Amplifier
The M ONE X is a compact monoblock for subwoofers based on current Class D technology. It drives 1-Ohm loads, and its current capability suits 2 x 2-Ohm subwoofers with parallel-wired voice coils. Its extensive feature set and small dimensions make installation straightforward.
Special highlights are the smart high-level input with the ADEP circuit (Advanced Diagnostics Error Protection), which prevents diagnostic error messages and loss of functions such as fader control in OE radios without unnecessarily loading the radio’s speaker outputs at high volume, and TwinPower Link, which combines two amplifiers in bridged mode into one powerhouse.
Key Features
- High output: 400 W RMS at 4 Ohms, 700 W RMS at 2 Ohms and 1,030 W RMS at 1 Ohm; up to 1,180 W RMS at 1 Ohm in typical subwoofer applications
- TwinPower Link: two amplifiers combined in bridged mode deliver 1,400 W RMS at 4 Ohms or 2,060 W RMS at 2 Ohms
- Smart high-level input with ADEP: avoids diagnostic errors and loss of functions with OE head units
- Automatic turn-on: via the high-level input
- Integrated active crossover: low-pass, band-pass, subsonic filter and phase control
- Bass boost: 0–12 dB, 30–80 Hz
- Bass remote control: cable remote for subwoofer volume included
- Start-stop capability: the switched-mode power supply keeps the amplifier running when the battery voltage drops to 6 V during engine cranking
- SMD construction: surface-mounted device technology
- Class D efficiency: low heat dissipation thanks to high efficiency
Inputs & Outputs
- 2 x RCA inputs
- 2 x high-level speaker inputs
- 1 x remote input
- 1 x remote control input
- Input sensitivity: RCA 0.5–6 V, high-level 1.1–13 V
- Input impedance: RCA 20 kOhms, high-level 9–33 Ohms
- 1 x speaker output
Power & Amplifier Section
- 1 x 400 W RMS at 4 Ohms (≤1% THD+N)
- 1 x 700 W RMS at 2 Ohms (≤1% THD+N)
- 1 x 1,030 W RMS at 1 Ohm (≤1% THD+N)
- Maximum output: up to 1,180 W RMS at 1 Ohm (typical subwoofer application)
- TwinPower Link (two amplifiers): 1,400 W RMS at 4 Ohms, 2,060 W RMS at 2 Ohms
- Amplifier technology: Class D
- Frequency response: 10–250 Hz
- Signal-to-noise ratio: 95 dB (A-weighted)
- THD: 0.20%
- Damping factor: 150
- Fuses: 3 x 40 A Maxi fuse (APX); power rating 12 V DC, 106 A max.
DSP & Sound Tuning
- Low-pass filter: 50–250 Hz, adjustable
- Band-pass: 10–250 Hz, adjustable
- Subsonic filter: 10–50 Hz, adjustable
- Slopes: subsonic 12 dB/oct., low-pass 24 dB/oct.
- Bass boost: 0–12 dB, 30–80 Hz
- Phase: 0–180°, adjustable
Installation & Connectivity Notes
- Operating voltage: 10.5–16 V, for max. 5 seconds down to 6 V
- Idle current: 800 mA
- Operating temperature range: −40 °C to +70 °C
- SRC.1-MK2 subwoofer remote control is listed as an accessory on the product page
Technical Specifications
| Power RMS ≤ 1% THD+N | Normal operation (One amplifier) |
TwinPower Link (Two amplifiers) |
| – @ 4 Ohms | 1 x 400 Watts | 1 x 1,400 Watts |
| – @ 2 Ohms | 1 x 700 Watts | 1 x 2,060 Watts |
| – @ 1 Ohm | 1 x 1,030 Watts | – |
| – bridged @ 4 Ohms | – | – |
| – bridged @ 2 Ohms | – | – |
| Max. output power per channel*: | Up to 1,180 Watts RMS @ 1 Ohm | |
| Amplifier technology | Class D | |
| Inputs | 2 x RCA / Cinch 2 x Highlevel speaker input 1 x Remote In 1 x Remote control input |
|
| Input sensitivity | RCA / Cinch 0.5 – 6 Volts Highlevel 1.1 – 13 Volts |
|
| Input impedance RCA / Cinch | 20 kOhms | |
| Input impedance highlevel | 9 – 33 Ohms | |
| Outputs | 1 x Speaker output | |
| Output voltage RCA / Cinch | – | |
| Signal converter for digital input | – | |
| Frequency response | 10 Hz – 250 Hz | |
| Bass boost | 0 – 12 dB / 30 – 80 Hz | |
| Highpass | – | |
| Lowpass | 50 Hz – 250 Hz adjustable | |
| Bandpass | 10 Hz – 250 Hz adjustable | |
| Subsonic | 10 Hz – 50 Hz adjustable | |
| Phase | 0 – 180° adjustable | |
| Slope high- / lowpass | – | |
| Slope subsonic / lowpass | 12 / 24 dB/Oct. | |
| Signal-to-noise ratio digital input | – | |
| Signal-to-noise ratio analog input | 95 dB (A-weighted) | |
| Distortion (THD) | 0.20 % | |
| Damping factor | 150 | |
| Operating voltage | 10.5 – 16 Volts (max. 5 sec. down to 6 Volts) | |
| Idle current | 800 mA | |
| Operating temperature range | -40 °C to +70 °C | |
| Fuse | 3 x 40 A Maxi-fuse (APX) | |
| Power rating | DC 12 V ⎓ 106 A max. | |
| Additional features | Active, adjustable crossover, bass boost, phase shift, Start-Stop capability, highlevel input with automatic turn on function and Advanced Diagnostics Error Protection (ADEP), bass volume cable remote control | |
| Dimensions (H x W x D) | 50 x 320 x 154 mm / 2.00 x 12.60 x 6.06” |
* In typical applications as subwoofer amplifier
Scope of Delivery
1 x Amplifier HELIX M ONE X
1 x Cable remote control
1 x Mounting material
1 x Instruction manual














