Skip to content
APEX Customs Store
, ,

HELIX C FOUR

R29,499.00

4-channel high-end amplifier with integrated, active crossover

Available to order - stock confirmed before dispatch

WhatsApp Us
SKU: HA14106 Categories: , ,

Free nationwide delivery on this product

Mobicred through PayFast Buy now. Repay at your pace.
3 months R10,175 estimated per month
6 months R5,218 estimated per month
12 months R2,743 estimated per month

Select Mobicred on the secure PayFast payment screen.

Final online selling price
Prefer certainty before payment?Supplier stock changes daily. Ask APEX to confirm this exact SKU first. Checks received now resume Wednesday, 28 October 2026 at 08:00 SAST.
Check live stock
Comparing this model?

Build a live shortlist by product type, budget and brand. Fitment and complete-system compatibility remain separate checks.

Product overview

Audiophile sound quality combined with impressive output power

The C FOUR is a high-end 4-channel amplifier that has been designed down to the last detail for ultimate sound quality. Audiotec Fischer’s proprietary ultra low-noise and ultra low-distortion Class A driver stage feeds a total of 32 hand-selected MOSFET power transistors, resulting in an incredible damping factor of 1,000 for relentless control of every loudspeaker. The intelligent regulation of the power supply assures stable conditions for the output stages and therefore phenomenal output power independent of the cars battery voltage. In combination with the optionally available digital input module HDM 2, the C FOUR demonstrates the perfect transition to the digital era. The HDM 2 accepts digital audio signals up to 96 kHz sampling rate via its two optical inputs followed by cutting-edge BurrBrown D/A converters with 32 Bit resolution that transform the signals back to the analog domain. Therefore the C FOUR is absolutely future-proof and perfectly prepared for the combination with our digital signal processors.

Key features

  • Extremely broadband Class AB amplifier with eight selected MOSFET transistors per channel for exceptional sound quality – ideal for High-Resolution audio
  • Ultra low-noise and distortion-free power amp drivers in Class A technology
  • Enormous damping factor of 1,000 @ 4 Ohms for perfect speaker control
  • Optionally available HELIX Digital Input Module (HDM) to extend the amplifier with two optical digital inputs in SPDIF format
  • Integrated, active crossover with highpass, lowpass and bandpass
  • Regulated DC / DC switching power supply with Start-Stop capability down to 6V supply voltage
  • Microprocessor-based monitoring of amplifier status including temperature-dependent fan control
  • Input Mode switch for flexible routing of the input signals
  • Cutting-edge BurrBrown D/A converters with 32 Bit resolution in combination with the optional HDM 2 module
  • Massive 24-carat gold-plated power and speaker terminals
  • Quad-layer PCB with extra-solid 70μ copper traces for lowest possible losses and SMD (Surface Mounted Device) manufacturing technology

Technical specifications

Technical data
– @ 4 Ohms4 x 150 Watts
– @ 2 Ohms4 x 220 Watts
– @ 1 Ohm–
– bridged @ 4 Ohms2 x 440 Watts
– bridged @ 2 Ohms–
Max. output power per channel*Up to 250 Watts RMS @ 2 Ohms
Amplifier technologyClass AB
Inputs4 x RCA / Cinch | 1 x Remote In | Optional via HDM 2 module: | 2 x Optical SPDIF (28 – 96 kHz)
Input sensitivityRCA / Cinch 1 – 8 Volts
Input impedance RCA / Cinch7.5 kOhms
Input impedance highlevel–
Outputs4 x Speaker output
Output voltage RCA / Cinch–
Signal converter for digital input–
Frequency response10 Hz – 80,000 Hz
Bass boost–
Highpass15 Hz – 4,000 Hz adjustable
Lowpass15 Hz – 4,000 Hz adjustable
Bandpass15 Hz – 4,000 Hz adjustable
Subsonic–
Phase–
Slope high- / lowpass12 dB/Oct.
Slope subsonic / lowpass–
Signal-to-noise ratio digital input–
Signal-to-noise ratio analog input112 dB (A-weighted)
Distortion (THD)< 0.007 %
Damping factor> 1000
Operating voltage9 – 16 Volts (max. 5 sec. down to 6 Volts)
Idle current2400 mA
Operating temperature range-40 °C to +70 °C
Fuse3 x 30 A LP-Mini-fuse (APS)
Additional featuresActive, adjustable crossover, HDM slot, input mode switch, High-Resolution audio, Start-Stop capability
Dimensions (H x W x D)37.1 x 430 x 240 mm / | 1.46 x 16.93 x 9.45"
Product properties
Dimensions – width< 450 mm
Dimensions – depth< 250 mm, < 300 mm, < 350 mm, < 400 mm, < 450 mm
Dimensions – height< 40 mm, < 50 mm, < 60 mm
Output power @ 4 Ohms> 30 Watt, > 50 Watt, > 70 Watt, > 100 Watt
Output power @ 2 Ohms> 30 Watt, > 50 Watt, > 70 Watt, > 100 Watt, > 200 Watt
Load stability2 Ohm, 4 Ohm
Signal-to-noise ratio> 80 dB, > 85 dB, > 90 dB, > 95 dB, > 100 dB, > 105 dB
THD< 0,01 %, < 0,05 %, < 0,1 %
Advanced featuresHigh-Res audio, Regulated power supply, Start-Stop capability

What you are ordering

The exact HELIX model shown above, APEX catalogue SKU HA14106. Review the listed inputs, outputs, impedance and system requirements before ordering.

Technical information verified against the official Audiotec Fischer product page.

Brand

HELIX

Product group

Amplifiers

Inputs

4 x RCA / Cinch, 1 x Remote In, Optional via HDM 2 module:, 2 x Optical SPDIF (28 – 96 kHz)

Outputs

4 x Speaker output

Frequency response

10 Hz – 80,000 Hz

Signal-to-noise ratio

> 80 dB, > 85 dB, > 90 dB, > 95 dB, > 100 dB, > 105 dB

THD

< 0,01 %, < 0,05 %, < 0,1 %

Dimensions (H x W x D)

37.1 x 430 x 240 mm /, 1.46 x 16.93 x 9.45"

Output power at 4 Ohms

4 x 150 Watts

Output power at 2 Ohms

4 x 220 Watts

Output power at 1 Ohm

–

Bridged output at 4 Ohms

2 x 440 Watts

Bridged output at 2 Ohms

–

Max. output power per channel

Up to 250 Watts RMS @ 2 Ohms

Reviews

There are no reviews yet.

Only logged in customers who have purchased this product may leave a review.

Make a confident choice

What matters for this product

Open Help Centre
APEX SIGNAL

Useful product intelligence. Nothing noisy.

Selected new products, honest comparisons and the best work leaving the APEX workshop.

Scroll to Top