【HELIX M-FOUR DSP | DSP Amplifier with Built-in 4ch Power Amplifier】

HELIX M-FOUR DSP is for those who want to fine-tune their factory audio a bit more, or for those considering replacing speakers and adding a subwoofer.

In a compact body, it integrates a 10ch DSP and a 100W×4ch power amplifier. Using time alignment, equalization, crossover, and more, you can create a sound tailored to your seat position and speaker layout inside the vehicle.

With a factory system, it’s difficult to precisely adjust the left/right volume and the time it takes sound to reach within the cabin. By combining the M-FOUR DSP, you can align the vocal position, achieve a more cohesive sound, and tune the continuity from bass to treble—bringing your everyday music closer to a well-balanced sound that’s easy to enjoy in the car.

Because it supports high-level input, it also makes system upgrades easier while keeping the factory navigation system and factory audio. It supports optical digital input as well, so depending on your system configuration you can choose a more flexible connection method.

Not only can it be used as a 4ch amplifier, it also supports a 2ch configuration via bridged connection. You can plan the configuration to match your vehicle specifications and the sound you’re aiming for—for example, to drive the front speakers properly, or to prepare for future system upgrades.

However, a DSP amplifier is not a product where the sound is complete just by installing the main unit. The final outcome is determined by everything from confirming the input signal, selecting the right combination with the speakers, setting gain and crossover, time alignment, and adjusting the listening feel inside the vehicle.

Even with the same M-FOUR DSP, recommended ways to use it vary depending on the vehicle model, factory system, speakers, and whether or not you have a subwoofer. At Logon, we propose a reasonable setup while confirming your current system, the music you usually listen to, and your preferences regarding sound.

If you want to “fine-tune the sound while making use of the factory audio,” “it’s not enough with speaker replacement alone,” or “you want to upgrade the system in the future,” please feel free to contact us. Let’s think together about how best to use the M-FOUR DSP for your vehicle.

■ Main Specifications / Specs

【Basic Information】

Product name: M-FOUR DSP
Brand: HELIX
Type: DSP amplifier with built-in 4ch power amplifier
Output stage operating class: Class D operation
Weight: 2.3kg

【DSP / Sound Adjustment】

DSP: 64-bit processor × 1
DSP clock frequency: 295MHz
Operating sample rate: 48kHz / 24bit
A/D converter: 24bit
D/A converter: 24bit
Level adjustment step (each section): 0.10dB / step
Time alignment step: 7.1mm / step
Output level: 5.0dB to −30dB

【Channel / Output】

Channel mode: 2ch / 3ch / 4ch
Output power: 100W × 4ch (4Ω stereo)
Output power: 100W × 4ch (2Ω stereo)
Output power: 200W × 2ch (4Ω bridged)
Damping factor: 100 or more
RCA output: 6ch
Maximum output voltage: 6V
Remote output: 2 channels
Remote output current: 500mA (maximum)

【Input / Connections】

RCA input: 6ch
High-level input: 6ch speaker input
Optical digital input: TOS type × 1 system
Optical digital input support: SPDIF / 12–96kHz / 24bit
RCA input sensitivity: 1–4V
High-level input sensitivity: 5–20V
RCA input impedance: 22kΩ
High-level input impedance: 9–33Ω or 20kΩ (ADEP.3 auto switching)
Auto power-on function: Supported (for high-level input)
Input impedance auto switching: ADEP.3
Control input terminal: Supported
PC connection: USB mini terminal
HELIX EXTENSION CARD: No settings

【Performance】

Frequency response: 20–22kHz (+0 / −1dB)
Total harmonic distortion: 0.015%
S/N ratio: 108dB or more (with digital input)
S/N ratio: 105dB or more (with analog input)

【Power / Main Unit】

Operating power supply voltage: 10.5–16.0V
Short-term power supply voltage drop: for 5 seconds, down to 6V supported
Idle current: 1.5A or less
Built-in fuse: ATO 30A × 2 (on the PCB)
Dimensions: W154 × H50 × D230mm
Included accessories: USB cable (1.8m), hex wrench