◆ AC Series · Compact Full-Range Digital 4-Channel
AC600K4
Compact Full-Range Digital 4-Channel Amplifier
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RMS Power 100W × 4 @ 4Ω
Impedance 2-Ohm Stable
Input Switch 2CH / 4CH
PCB 4-Layer SMD
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◆ AC Series · Compact Full-Range Digital 4-Channel · 2026 Edition
Compact Full-Range Digital 4-Channel Amplifier

AC600K4

Four channels. 100 watts RMS each — every one tested simultaneously at rated load, not a combined figure built from a single channel measured in isolation. Bridge any two and you're at 350 watts RMS. Compact chassis, honest numbers, no asterisks. The AC600K4 is the entry point to the AC Series standard — the same verified power promise that runs all the way to the top of the line.

100W
× 4CH @ 4Ω
175W
× 4CH @ 2Ω
350W
× 2 Bridged @ 4Ω
4CH
Amplifier
Lab-Verified Power. Every Channel. Every Build. No Inflated Peak Numbers. Ever.
Every Aunex amplifier is independently tested at rated power. What's on the box is what comes out of the terminals.
Power Output · RMS · Verified @ 14.4V DC
AC600K4
Compact Full-Range Digital 4-Channel
4Ω · 4CH
100 W × 4 RMS
2Ω · 4CH
175 W × 4 RMS
4Ω · 2CH
350 W × 2 Bridged RMS
The Aunex Standard

Four Channels.
One Standard.
No Compromises.

Most 4-channel amplifiers at this price point overstate their output, spread peak-rated watts across four channels, and leave your drivers working harder than they should. The AC600K4 does not.

Every channel delivers 100 watts RMS at 4 ohms — independently tested, not claimed. Run all four for a complete front and rear stage, or bridge to two channels for 350 watts RMS each. One amplifier, one honest number, no fine print.

"What's on the box is what comes out of the terminals — no inflated peak numbers, ever."

— The Aunex Power Promise
Technical Specifications

Everything You Need.
Nothing You Don't.

Class / Topology
Full-Range Digital
4-Channel Amplifier
Rated Power @ 4Ω RMS
100W × 4
Rated Power @ 2Ω RMS
175W × 4
Bridged Power @ 4Ω RMS
350W × 2
Impedance Stability
2-Ohm Stereo Stable
Frequency Response
10Hz – 25kHz
Signal-to-Noise Ratio
>89 dB
THD + Noise
<1.0%
Low-Pass Crossover
40Hz – 400Hz (Variable)
High-Pass Crossover
400Hz – 4kHz (Variable)
Crossover Slope
12dB/Octave
Bass Boost
0 – 12dB
Input Switch
2CH / 4CH
Input Sensitivity
400mV – 20V
Operating Voltage
7.5 – 17V DC
Efficiency
87%
PCB Construction
4-Layer SMD Technology
Heatsink
Custom Anodized Extruded
Dimensions (W×H×L)
8.31 × 2.05 × 5.71"
211 × 52 × 145 mm
Engineering Details

Built for the
Real World.

The AC600K4 puts verified four-channel power into a compact chassis without the compromises that define the category. Four independent channels on a 4-layer board, all independently tested, all individually protected. Every feature below earns its place.

4-Channel

Four Verified Channels — Any Configuration

Run all four channels across a complete front and rear stage at 100W RMS each. Bridge any two channels for 350W RMS — the same verified standard applies in every configuration. One amplifier, multiple install options, no power compromises.

4-Layer PCB

4-Layer PCB · SMD Technology

Unlike the 2-layer boards standard at this price point, the AC600K4's custom 4-layer PCB incorporates dedicated internal power and ground planes. Those buried copper layers act as a Faraday shield — eliminating alternator whine and EMI at the source, not masking it downstream. The added copper mass also increases structural rigidity and thermal dissipation, so the board runs cooler under sustained load and survives the road vibration that eventually fractures solder joints in lesser builds.

Crossovers

Wide-Range Variable HPF and LPF · 12dB/Octave

High-pass filtering from 400Hz–4kHz and low-pass filtering from 40Hz–400Hz give you surgical control over what each channel receives — protect tweeters, eliminate overlap, and tune the system precisely without an outboard processor. The 12dB/octave slope provides a controlled, musical rolloff ideal for coaxial and component setups alike.

4-Way Protection

Self-Recovering 4-Way Protection Circuitry

Thermal shutdown, short circuit protection, under-voltage and over-voltage protection work across all four channels independently. Short circuit protection is self-recovering — the amplifier detects the fault, shuts down the affected channel, and resumes operation automatically once the condition clears. No manual reset required.

Visual Clipping

Real-Time LED Visual Clipping Indicator

Visual feedback at a glance. The integrated LED clipping indicator gives you instant confirmation that you're maximizing output without distorting your drivers — a feature typically reserved for amplifiers at twice the price point. Set your gain correctly once and know it stays there.

Balanced Inputs

Zero-Point Balanced Inputs (CMRR)

Fully balanced architecture with high CMRR technology actively neutralizes electrical noise at the entry point. High-level inputs accommodate OEM source units directly. DC auto turn-on means the amp powers on reliably with the vehicle regardless of whether a remote turn-on wire is available — a clean drop-in for factory systems without an aftermarket head unit.

Solid Nickel

Solid Nickel-Plated Terminals

Copper corrodes. Untreated steel corrodes faster. Nickel doesn't. Our industrial-grade block terminals are solid nickel-plated to maintain a low-resistance connection years after install — not just on day one. Every milliohm of contact resistance you eliminate at the terminal is headroom that reaches your drivers instead of turning into heat at the connector.

On/Off Delay

Soft On/Off Delay

An intelligent soft-start circuit sequences internal power ramping at turn-on and turn-off, eliminating the thump or pop that travels through your speakers every time you start or stop the vehicle. Repeated voltage transients stress tweeters and mid-range drivers over time — the AC600K4 handles the sequencing internally so your drivers don't absorb the hit.

The Aunex Difference

Every Standard.
Every Unit.

These aren't options, upgrades, or premium-tier exclusives. Every feature listed below ships on every AC600K4 — verified before it leaves the facility.

Independently Verified RMS
Power rated and confirmed by independent testing. No peak figures. No asterisks. What's on the box is what measured on the bench — all four channels.
All 4 Channels Tested Simultaneously
Every channel driven at rated load at the same time. Not one channel measured while three idle. The same verified standard in every configuration — stereo, bridged, or mixed.
4-Layer SMD PCB
Double the copper layers of a standard build. Lower impedance power planes, better thermal dissipation, structural rigidity that survives the road.
LED Clipping Indicator
Real-time visual confirmation you're at max output without crossing into distortion. A tuning tool, not a decoration. Included standard — not an add-on.
Bridge Mode — 350W × 2
Bridge any two channels for 350W RMS at 4 ohms. Run a bridged output alongside a stereo front stage — or bridge both sets for maximum output from a single amplifier.
Balanced Audiophile Inputs
Works with any source — factory OEM head units via high-level input, aftermarket receivers, or DSP processors. Input sensitivity spans 400mV to 20V. No additional adapter required.
2CH / 4CH Input Switch
Seamlessly switch between a 2-channel or 4-channel input configuration to match your source unit's output — no adapters, no rewiring.
Self-Recovering Protection — Always Active
Thermal, short-circuit, over-voltage, and under-voltage protection across all four channels simultaneously. Short circuit protection is self-recovering — no manual reset required.
CMRR — Common-Mode Rejection
Alternator whine, ignition interference, and ground loop hum cancelled at the point of entry — so you're not chasing a noise floor problem with ground loops and ferrite cores after the fact.
Soft On/Off Delay
Intelligent soft-start sequencing eliminates the thump or pop through your speakers at every key turn. Your drivers don't absorb the voltage transient — the amp handles it internally.

The Industry Sells
Numbers. We Sell
Results.

Four channels. One verified standard. The AC600K4 delivers 100 watts RMS to every channel — independently tested under real-world conditions, printed on the box without qualification. No combined peak totals. No inflated figures. No fine print. The same 4-layer PCB, the same protection circuitry, the same CMRR input architecture found across the AC Series. This is the standard — not the compromise.

100 verified watts · per channel · 4Ω