B&W LM1 Micro Monitor

Commentary

A small speaker system developed for both home audio and car audio.

There were two variations of LM1 Micro Monitor : LM1 and LM1/PM.
LM1 is an enclosure type and can be used as a stationary type for home listening, car audio, yacht, etc.
The LM1/PM is a recessed panel mount type, and is a car audio embedded type that is installed by combining three types of spacers.

LM1 is equipped with a mode switch on the front baffle to enable network switching.
The 0 position has a crossover frequency of 3 kHz, and the + position has a crossover frequency of 4.5 kHz. This crossover frequency was determined by computer analysis with a precision of 1/12 octave. The 4 Ω position suitable for automotive power amplifiers is +, and the 8 Ω position suitable for home power amplifiers is 0.

A 10 cm cone type woofer is installed in the low range.
A cone made of polyamide fiber is used for the diaphragm of this unit, and a voice coil with a diameter of 26 mm with excellent heat resistance is used. In addition, the suspension material is highly compliant and stable against temperature rises.

A 2 cm dome type tweeter is installed in the high range.
Polyester diaphragm is used for the diaphragm, and voice coil has a diameter of 20 mm.

The crossover network consists of 13 elements and consists of 18dB/oct. high-pass and low-pass filters.

The enclosure and front panel are die-cast zinc alloy, and the inside of LM1 is covered with sound absorbing material made of hydrocarbon compound to reduce coloring.
The surface treatment is coated by dissolving fine particles of neoprene rubber in a special solvent.

An APOC (Audio Powered Overload Circuit) circuit composed of 20 elements is mounted as an overload protection circuit.

There are 5 color variations such as charcoal gray, blue, brown, red and beige.

Model Rating

Method	2-way, 2-Speaker, Setting Free Type
Type	LM1 : closed system LM1/PM : Panel Mount Type
Unit	For low band : 10.0 cm cone type For high-pass : 2.0 cm dome type
Frequency characteristic	LM1 LM1/PM : : 95 Hz to 25 kHz ± 4 dB (2m distance, front, free field, 0 position) 80 Hz to 16 kHz ± 4 dB (1/3oct-pink noise, rear tray with microphone in driver position, + position) 95 Hz to 25 kHz ± 4 dB (2m distance, front, free field, 0 position) 31 Hz to 16 kHz ± 4 dB (1/3oct pink noise, door or rear tray installed, microphone in driver position, + position)
Impedance	8 Ω (0 position) 4 Ω (+ position)
Crossover frequency	3 kHz (0 position) 4.5 kHz (+ position)
Overload protection circuit	APOC Circuit (Audio Powered Overload Circuit)
Allowable input	When used in a car : Compatible with an amplifier (4 Ω) with output of 10W or more For indoor use : Compatible with an amplifier (8 Ω) with an output of 20W or more No upper limit due to built-in APOC
Output sound pressure level	81dB/W/m (8 Ω, 0 position) 85dB/W/m (4 Ω, + position)
External dimensions	LM1 : 240 mm wide x 155 mm high x 195 mm deep LM1/PM : Width 240x Height 155x Depth 70 mm
Weight	LM1:5.2kg LM1/PM:2.8kg