PSB CS630
Overview
The PSB CS630 is an in-ceiling speaker designed to deliver a full stereo signal from a single installation point. It uses a dual voice-coil design and two separate aluminum tweeters, allowing it to reproduce the left and right channels from a single cutout. The speaker can be wired in bipolar, dipolar, or conventional stereo mode, offering flexibility for different home theater configurations.
A technical design engineered for acoustic versatility
The CS630 centers around a 165 mm woofer equipped with a dual voice coil, a technical feature that fundamentally sets it apart from conventional in-ceiling speakers. This transducer uses an injection-molded, fiber-loaded polypropylene cone—material chosen by PSB for its balanced mechanical properties between rigidity and internal damping. The rubber surround ensures controlled cone excursion, enabling low-frequency reproduction down to 50 Hz without notable distortion, even at high sound levels.
The two 19 mm black anodized aluminum dome tweeters are mounted on a pivoting plate, allowing post-installation adjustment of high-frequency dispersion. This is particularly relevant in constrained spaces where the optimal speaker position may not align with the primary listening area. Each tweeter benefits from a carefully calculated waveguide, extending its response into the midrange and creating a smooth transition with the woofer in the critical crossover region.
The crossover, set at 2100 Hz with a 4th-order Linkwitz–Riley slope (LR4), reflects a rigorous approach to frequency management. This filter topology, known for its phase linearity in the transition zone, ensures temporal coherence between the different drivers—crucial for maintaining precise stereo imaging despite the physical proximity of the channels.
Configuration possibilities rarely matched
The woofer’s dual voice coil opens up uncommon wiring options for an in-ceiling speaker. In a classic stereo configuration, the two coils respectively receive the left and right channel signals, allowing a single speaker to reproduce a full stereo signal. This approach is well-suited to small spaces like bathrooms, hallways, or kitchens where installing two separate speakers would be problematic or aesthetically questionable.
Bipolar mode radiates both channels in phase, creating a coherent, enveloping sound field that is particularly suitable for ambient sound applications. Conversely, dipolar mode introduces a 180-degree phase shift between channels, generating the diffuse acoustic effect desired for surround channels in home theater setups. This feature delivers the recommended spatial de-correlation for effects speakers without requiring the installation of specialized on-wall units.
The option to wire CS630s as rear surround speakers in a 7.1 configuration showcases PSB’s modular vision. Two CS630s can handle four distinct effects channels, significantly simplifying installation while maintaining tonal coherence with the rest of the system—fundamental for creating a homogeneous sound bubble.
Installation and integration: simplicity in the service of performance
The CS630’s reinforced metal dogleg mounting system reflects a focus on installation ease. These rotating clamps deploy progressively as they’re tightened, distributing the load over a wide ceiling area while guaranteeing impeccable stability despite the speaker’s 2.2 kg weight. The supplied cutout templates eliminate guesswork during drilling, ensuring an accurate fit in the 212 mm diameter opening.
The 114 mm mounting depth is modest for a speaker of this technical complexity, allowing installation in most standard drop ceilings. Gold-plated spring terminals accept cables up to 12 AWG for direct connection, as well as banana plugs or pin connectors, offering universal compatibility with different wiring standards.
Aesthetics haven’t been overlooked: frameless magnetic grilles, available in round (240 mm) and square (241 mm) versions, visually disappear into the ceiling. The acoustically transparent scrim covering them can be painted to blend perfectly with existing decor, while the absence of a visible frame ensures particularly discreet integration.
Independent level switches for the woofer and tweeters, accessible after installation, allow you to tailor the tonal balance to the room’s acoustic characteristics. This is crucial in spaces with complex geometries or reflective materials, where fine EQ can dramatically transform sound quality.
Technical specifications
Drivers
- Woofer: 165 mm with dual voice coil
- Injection-molded, fiber-loaded polypropylene cone
- Rubber surround
- Tweeters: 2 × 19 mm black anodized aluminum domes
- Mounted on a swiveling plate for optimal placement
Acoustic response
- On-axis frequency response at 0° ±3 dB: 50–20,000 Hz
- Sensitivity
- Anechoic chamber: 85 dB
- Listening room: 87 dB
- Crossover: 2100 Hz, precision LR4
Electrical characteristics
- Nominal impedance: 10 Ω
- Minimum impedance: 8 Ω
- Recommended input power: 10–100 W
Dimensions and installation
- Type: open back
- Cutout diameter: 212 mm
- Mounting depth: 114 mm
- Round grille diameter: 240 mm
- Square grille: 241 × 241 mm
- Weight: 2.2 kg per speaker
Finish and accessories
- Finish: white
- Frameless magnetic grilles: round and square included
- Paintable, acoustically transparent scrim
- Robust mounting clamps and cutout templates included
Highlights
- Easy installation with robust mounting system and supplied cutout templates
- Post-installation adjustments: rotate the woofer and tweeter module for precise sound dispersion, reducing reflections and losses
- Paintable magnetic grilles for discreet integration in any environment
- Lightweight 2.2 kg for easy, secure mounting
- Seamless transition between woofer and tweeters thanks to the precision crossover
Frequently Asked Questions
How does the single-speaker stereo mode actually work?
The CS630 woofer’s dual voice coil simultaneously receives the left and right channel signals. Each coil controls part of the cone’s movement, creating an acoustic summation of both channels in the bass. The two tweeters reproduce the high frequencies of each channel separately, maintaining some spatial separation. This setup is particularly suitable for small spaces where the listener naturally sits in the center of the coverage area.
Can the CS630 replace two traditional stereo speakers?
In tight spaces or passage areas, the CS630 offers an elegant way to deliver a full stereo signal. However, channel separation remains physically limited compared to two distinct speakers. For critical listening or large rooms, two separate speakers will always provide a wider, better-defined stereo image. The CS630 excels where the balance between performance and installation constraints favors simplicity.
What amplification is recommended for the CS630?
With a real-world sensitivity of 87 dB and a nominal impedance of 10 ohms (minimum 8 ohms), the CS630 is relatively easy to drive. The recommended power range of 10 to 100 watts offers ample latitude. An amplifier delivering 30 to 50 watts per channel is sufficient for most home applications, while commercial installations or larger rooms will benefit from greater headroom.
How do I optimize the positioning of the pivoting tweeters?
After installation, aim the tweeters toward the main listening area. In a hallway, point them along the axis of movement. For a bathroom, target the space between the shower and the sink. In a surround home theater setup, aim them 45 degrees relative to the walls to maximize dispersion. Adjustment is done by manually rotating the tweeter plate—no tools required.
Is the CS630 suitable for insulated ceilings?
The CS630’s open-back design uses the ceiling’s cavity as the acoustic load. Moderate insulation doesn’t significantly affect performance, but a fully obstructed ceiling could alter low-frequency response. In such cases, the woofer level settings generally compensate. For critical installations, PSB offers optional backcans that standardize the enclosure volume.
Can four CS630s be used for a full 7.1 system?
Technically possible, this configuration fully leverages the CS630’s versatility. Two speakers in dipole mode handle the side surround channels (5.1 and 6.1), while two others in stereo mode cover the rear surrounds (7.1). This approach ensures perfect tonal consistency across all effects channels, simplifies wiring, and reduces the number of ceiling cutouts while delivering convincing spatialization for home theater.
- Eco-contribution included in the sale price.
