I’ve been spending some time with the ACS Eclipse 500, and they represent a massive shift for a company known primarily for their custom silicone work. These are hybrid universals that actually prioritise long-term ear health and comfort without gutting the low-end. Here’s the breakdown:
The Build: Anodized Aluminium & Steel
Unlike the resin shells you see everywhere else, these feel like precision tools.
- Shells: Die-cast aluminium with a gorgeous copper-tone anodized finish.
- Nozzles: CNC-machined stainless steel. The cool part? You get three different lengths (Standard, Short, and Extended) to dial in your specific ear canal depth.
- Fit: They sit remarkably flush. Even if you have smaller ears, the ergonomic shape avoids that "bulky" look common in multi-driver setups.
- Cable: The included 1.5m cable is a 2-pin twist cable made of silver-plated copper. This material is chosen to maintain high signal integrity and reduce oxidation over time.
The Hardware: A 4-Driver Hybrid Engine
ACS didn't play it safe with the driver configuration. They’ve gone for a best of both worlds approach:
- Sub-Bass: A dedicated 8mm dynamic driver handles the lows for that analogue punch.
- Mids/Highs: Two Knowles Balanced Armatures for surgical precision.
- The "Air": A Knowles Super Tweeter that pushes the response out to 24kHz (Hi-Res certified).
Key Specifications:
- Crossover: Passive 3-way crossover to ensure seamless driver integration.
- Frequency Response: 10Hz – 24kHz.
- Impedance: 28 Ohms (easy to drive via smartphones or wireless belt packs).
- Sensitivity: 108dB @ 1kHz
The "X-Factor": Ambient Venting
The most annoying part of IEMs is the "vacuum seal" feeling. The Eclipse 500 uses a 17dB passive-ambient filter. It lets air move in and out, which does three things:
- Eliminates pressure build-up on your eardrum (no more "thumping" sounds when you walk).
- Drastically reduces listening fatigue.
- Opens up the soundstage so it feels more like a pair of open-back headphones than earplugs.
Unboxing & Accessories
The packaging is professional and surprisingly comprehensive. In the box, you’ll find:
- The monitors and a high-quality 2-pin silver-plated copper twist cable.
- All three sets of stainless steel nozzles.
- The product comes with slow-rebound high-density foam tips in various sizes (small, medium, and large) to ensure a secure seal and comfort.
- A rugged, pebble-grain leather zip case with a carabiner for stage use.
Pro-Level Upgrades
If you want to take the setup further, there are two specific additions worth looking at:
- The Go Link DAC: A matching copper-finished Hi-Res DAC that ensures you’re getting the full 24kHz resolution out of your phone or laptop.
- Custom Sleeves: You can actually get medical-grade silicone sleeves custom-molded to your ears that slide right onto these universals.
The Verdict
At $1,650AUD, these aren't "entry-level," but they are built to last a career. If you’re a musician who spends 4 hours a day with things in your ears, or an audiophile who hates the "closed-in" feeling of traditional IEMs, these are a serious breath of fresh air.
