Carbon Special Black Label

REL Acoustics Carbon Special Black Label – Reference Bass Extension

At Son Ultime, bass integration is not merely about adding impact, but about complementing the entire spectrum with precision, speed, and coherence. The REL Carbon Special Black Label stands out as a reference solution to achieve this goal.

Designed as an evolution of REL Acoustics' most performing platforms, the Carbon Special Black Label combines speed, control, and dynamic capability, allowing seamless integration with the most demanding high-fidelity systems.

6-Stack Configuration – System Presented at the Montreal Audiofest 2026

At Son Ultime, we have chosen to fully exploit the potential of the REL Carbon Special Black Label by integrating a 6-Stack configuration into our system presented at the Montreal Audiofest 2026.

This approach involves using six subwoofers to:

• Uniformize room response
• Reduce standing waves
• Improve perceived bass speed
• Increase dynamics without overload
• Maintain perfect coherence with the main speakers

The result is not louder bass, but more structured, faster bass, perfectly integrated with the rest of the spectrum.

Architecture and Transducers

The Carbon Special Black Label is based on an architecture optimized for speed and precision, combined with high dynamic capability.

• Carbon fiber main driver
• Lightweight and extremely rigid structure
• Passive radiator optimized for bass extension
• Integrated high-power amplification
• Fast response suitable for high-resolution systems

The use of carbon fiber allows for better diaphragm acceleration, reducing distortion and improving the intelligibility of low frequencies.

Observed Sound Behavior at Son Ultime

In our reference systems, the Carbon Special Black Label demonstrates an exceptional ability to integrate without localization effects.

• Fast and perfectly articulated bass
• Deep extension without overhang
• Controlled physical impact
• Improvement of the overall soundstage
• Better perception of micro-details
• Increased sound image stability

The addition of properly calibrated REL subwoofers improves not only the bass but the entire musical reproduction.

Technical Specifications

System Integration According to the Son Ultime Approach

At Son Ultime, REL subwoofers are never used in isolation. They are part of a global system optimization strategy.

Recommended pairings:

• Bowers & Wilkins 800 series speakers
• Acora Acoustics speakers
• Audio Research amplification
• MSB Technology digital sources
• Shunyata Research cabling and power supply
• HifiRose streaming and Silent Angel optimization
  

Positioning, filtering, and calibration are precisely adjusted to achieve invisible and coherent integration.

Why a Multi-Subwoofer Configuration

The multi-subwoofer approach used by Son Ultime is based on fundamental acoustic principles:

• Reduction of modal room resonances
• More uniform energy distribution
• Reduction of dips and peaks
• Improvement of temporal coherence

The 6-Stack configuration presented at the Montreal Audiofest 2026 represents an extreme application of this approach, aiming for optimal performance.

Son Ultime Approach

At Son Ultime, bass integration is a critical step in system design. We analyze:

• The modal response of the room
• Subwoofer positioning
• Phase and delay
• Interaction with main speakers
• Overall system balance

It is this approach that allows the Carbon Special Black Label to function as a natural extension of the system rather than an artificial addition.

Discover our REL Carbon Special Black Label 6-Stack configuration at the Montreal Audiofest 2026 or schedule a personalized demonstration at Son Ultime.