Velodyne SPL-X 12

Twenty-two years after the introduction of the Digital Drive series, the first to offer automatic room calibration on a subwoofer, Velodyne Acoustics is updating its high-end range with the SPL-X series. The SPL-X 12 pursues this philosophy with an updated design: carbon fiber driver, powerful Class D amplification, and DSP controllable via mobile app.

A driver designed for extreme excursion

The 30 cm (12-inch) driver features a carbon fiber cone mounted on a dual spider suspension. This configuration, combined with a basket ventilated by three channels, allows for wide excursions while keeping the cone perfectly centered. The 102 mm (4-inch) voice coil is wound in four layers and driven by a triple ferrite magnet system. This design generates high motor force, even at high output, resulting in fast, articulate bass.

Compared to the SPL-X 10 and its 76 mm coil, the 12-inch model offers greater dynamic headroom and deeper extension. Velodyne specifies usable response from 15 Hz at ±10 dB, and linear behavior (±3 dB) between 25 and 200 Hz.

Class D amplification and power reserves

The built-in amplifier delivers 1200 W RMS continuous power and can reach 1700 W peak. The choice of a Class D topology serves a dual purpose: compact module size and high efficiency. Even at full load, heat buildup remains limited, preserving power handling during demanding passages.

The low-pass filter is adjustable between 30 and 200 Hz, with four selectable slopes (12, 24, 36, or 48 dB per octave). An adjustable delay from 0 to 500 ms allows temporal alignment of the subwoofer with the main speakers. These settings can be adjusted via Velodyne’s AutoEQ app or directly on the rear panel.

Automatic calibration and parametric equalization

Velodyne supplies a measurement microphone with a mini tripod, which connects via USB-C to a smartphone or tablet. The AutoEQ procedure takes place in two steps: a near-field measurement to characterize the subwoofer, then a listening-position measurement to capture the room’s acoustic interactions. The app then calculates an appropriate correction.

Beyond automatic calibration, the app provides access to a six-band parametric equalizer, a subsonic filter, and a high-pass filter for the output to satellite speakers. Presets (cinema, jazz/classical, rock, gaming) provide quick starting points that can be adjusted to taste.

Versatile connectivity for various setups

The rear panel includes stereo and LFE RCA inputs, stereo and LFE XLR inputs, as well as a high-level input for connection to speaker binding posts. Corresponding outputs (RCA and XLR) simplify installing multiple subwoofers or integrating the sub into a system with external bass management.

The power mode selector offers three options. In the “Auto” position, the subwoofer detects the presence of a signal and automatically wakes up (with adjustable sensitivity threshold). The “Trigger” mode waits for a 12 V control signal, common on AV receivers. The “On” mode keeps the subwoofer permanently powered.

Construction and footprint

The sealed enclosure is made of HDF (high-density fiberboard) with internal bracing to limit unwanted vibrations. The understated black lacquer finish blends easily into a living room or dedicated theater room. A black fabric grille on an MDF frame protects the driver.

At 38 cm wide, 40 cm high, and 48 cm deep, the SPL-X 12 remains relatively compact for a subwoofer of this power. Its 35 kg weight (40 kg shipped), however, calls for two people to move it comfortably. The power supply supports voltages from 115 to 230 V without a manual switch.

Technical specifications

Driver and enclosure

• Driver: 12″ high-performance with three-channel vented basket, carbon fiber cone
• Suspension: dual spider for optimal control of cone excursion
• Voice coil: 4″ / 102 mm, four layers
• Magnets: triple ferrite system
• Enclosure: sealed HDF cabinet, reinforced construction to limit resonances

Amplification and digital processing

• Amplifier type: Class D
• RMS power: 1200 W
• Peak power: 1700 W
• Frequency response: ±10 dB: 15–280 Hz / ±3 dB: 25–200 Hz
• Low-pass filter: adjustable 30–200 Hz, slope 12 / 24 / 36 / 48 dB/octave
• Delay: 0–500 ms
• AutoEQ DSP: automatic calibration with microphone to adapt bass to the room acoustics

Connectivity and control

• Inputs: stereo / LFE RCA, stereo / LFE XLR, stereo high-level input
• Outputs: stereo / LFE RCA, stereo / LFE XLR
• Control via mobile app: volume adjustment, 6-band equalizer, subsonic and high-pass filters, presets

Power supply and features

• Automatic power-on with adjustable sensitivity
• Power mode selector: Auto / Trigger / On
• Grille: black fabric with MDF frame
• Voltage: 115–230 V

Dimensions and weight

• Dimensions (H x W x D): 380 x 400 x 480 mm
• Weight: 35 kg
• Shipping weight: 40 kg

Overview

The SPL-X 12″ is the solution for powerful, controlled bass, combining a high-performance carbon fiber driver with a large voice coil, a high-efficiency Class D amplifier, automatic DSP calibration (AutoEQ), comprehensive connectivity, and control via mobile app.