Match UP W8BMW-S

Match UP W8BMW-S – ultra-flat 8″ under-seat upgrade subwoofers for BMW

The Match UP W8BMW-S is the BMW bass upgrade within Audiotec Fischer’s MATCH UPGRADE range: a pair of ultra-flat 8″ subwoofers that fit the original under-front-seat positions of all BMW model ranges equipped with under-seat subwoofers. With one 2 Ω voice coil per woofer, they can replace the original subwoofers of the BMW HiFi sound system.

A very stiff fiberglass cone allows high, distortion-free sound pressure with a punchy, dynamic character, while the oversized 42.5 mm voice coil supports high power handling. BMW-specific baskets and connectors permit quick installation, and the very low mounting depth also makes the woofers suitable for compact sealed enclosures in universal applications. They combine well with the MATCH UP 7BMW and UP 7DSP amplifiers.

Key Features

• 2 x 8″ upgrade subwoofers: supplied as a pair for the BMW under-seat positions.
• Direct fit: mounts in the original under-front-seat positions of all BMW model ranges with under-seat subwoofers.
• BMW-specific baskets and connectors: quick and easy installation; BMW connection cables for the original harness included.
• Extremely stiff fiberglass cone: high sound pressure without distortion.
• Oversized 42.5 mm voice coil: for high power handling.
• 1 x 2 Ω per woofer: can replace the original subwoofers of the BMW HiFi sound system.
• Ultra-flat design: only 40 mm installation depth.
• Compact sealed boxes possible: works in enclosures from 3 L net volume.
• Amplifier match: combinable with the MATCH UP 7BMW and UP 7DSP amplifiers.
• Universal use: also suited to ultra-flat subwoofer builds outside BMW applications.

Drivers & Construction

Each woofer uses an extremely stiff fiberglass cone with 214 cm² cone area, driven by a 42.5 mm voice coil with 12.5 mm winding height and a single 2 Ω winding. The baskets and connectors are BMW-specific.

Acoustic Performance

• Power handling: 200 W RMS / 400 W max. (per woofer)
• Impedance: 1 x 2 Ω; DC resistance Re 2.0 Ω
• Sensitivity: 90 dB (1 W / 1 m)
• Resonance frequency Fs: 49 Hz
• Q factors: Qms 3.80, Qes 0.61, Qts 0.53
• Vas: 13.9 L; Cms 210 µm/N
• Force factor Bl: 7.1 Tm
• Moving mass Mms: 47.4 g; mechanical resistance Rms 3.97 kg/s
• Max. linear excursion Xmax: ±4.0 mm

Installation Notes

• Dimensions: outer diameter 239 mm (9.41″), installation diameter 175 mm (6.89″), installation depth 40 mm (1.57″).
• Vehicle fit: all BMW model ranges with under-seat subwoofers (see the manufacturer’s compatibility chart).
• Sealed enclosure: 3 L net, -3 dB at 63 Hz; suggested DSP: high-pass Butterworth 12 dB/oct at 40 Hz, EQ at 90 Hz (Q 3.0, -4 dB), low-pass Butterworth 24 dB/oct at 80–100 Hz.
• Vented enclosure, one woofer: 12 L net, port ø 60 mm (28 cm²), length 25 cm, tuned to 46 Hz, -3 dB at 45 Hz.
• Vented enclosure, two woofers: 24 L net, port ø 80 mm (50 cm²), length 20 cm, tuned to 46 Hz, -3 dB at 45 Hz.
• Vented DSP settings: high-pass self-defined at 40 Hz (Q 1.3), EQ at 67 Hz (Q 3.0, -3 dB), low-pass Butterworth 24 dB/oct at 80–100 Hz.

Technical Specifications

Scope of Delivery

2 x Subwoofer MATCH UP W8BMW-S
2 x BMW connection cable
1 x Mounting material
1 x Instruction manual