Напольная акустика — PMC IB2S XBD-AII

The IB2S XBD-AII is a twin-cabinet active reference monitor from PMC, aimed at professional mastering, mixing and post-production rooms working in stereo and surround. Introduced in 2019 as part of the second generation of the IB2S active range, it combines the three-way IB2S-AII master cabinet with a matching XBD bass cabinet, and moves all amplification and DSP into external rack-mounted electronics.

Key specs that matter

Each channel uses two 10-inch (250mm) carbon-fibre/Nomex piston bass drivers, the same units used in PMC's QB1, one in each cabinet, plus a hand-built 75mm soft-dome midrange and a 34mm soft-dome tweeter with acoustic radiator. Crossover points are 380Hz and 3.8kHz. Frequency response is 25Hz to 25kHz and maximum SPL is 128dB. Each cabinet has its own 2.4m transmission line. Amplification totals 3,225W per channel from DSP-controlled Class D modules - 2,400W for the two bass drivers, 550W for the midrange and 275W for the tweeter. Inputs are balanced analogue and AES3 digital up to 24-bit/96kHz. The combined system measures 150 x 33 x 56.4cm and weighs about 90kg per side.

Engineering and use context

The bass drivers use a flat, honeycomb carbon-fibre/Nomex piston in an extensively vented cast-aluminium chassis. A flat, ultra-rigid diaphragm behaves as a true piston without the cone flexing that curved paper or polymer cones show at high levels, and it can supply the high air pressure needed to drive a long transmission line. The XBD cabinet doubles the bass driver count and line length, adding about 3dB of low-frequency headroom for larger rooms. Placing the electronics in two 3U rack units per channel keeps heat and vibration out of the speaker cabinets and makes soffit or wall mounting practical, since the rear panels never need to be accessed after installation. All adjustments are made from an RJ45-connected desktop remote with a backlit display, which also stores three user presets and switches inputs. The cabinets can be stacked vertically or placed side by side to suit the room and console layout.

Pairing

The IB2S XBD-AII accepts a balanced analogue signal from a console, monitor controller or preamplifier, with input sensitivity adjustable from +4 to +16dB, or an AES3 digital signal directly from an interface. As a fully active system it needs no external amplifiers, and consistent voicing across the PMC IB range allows matching centre and surround monitors in multichannel rooms.

Alternatives

PMC's own IB2S-AII is the single-cabinet version with 2,025W of amplification per channel, for rooms that do not need the XBD bass extension.