Alesis M1 - page 10

About the M1 Active

10 M1 ACTIVE REFERENCE MANUAL

✪ If you’re in a hurry to get started, skip ahead to Chapter 2,

“Speaker Installation”, for connection and placement tips.

The M1 Actives combine a speaker and amplifiers in the same compact cabinet.

Powered monitors are growing in popularity over the traditional separate amplifier

and speakers for a number of reasons, convenience and ease of hookup being only

one of them. You can connect a powered speaker directly to any line-level source

(normally, the control room output of a mixer) simply by connecting a patch cord.

Another benefit is improved sound quality. With careful design, the speaker,

amplifier and electronic crossover can be optimised for each other. The M1 Actives

are biamplified, meaning that low frequencies and high frequencies are handled not

only by separate speakers (the tweeter and the woofer), but by separate amplifiers. A

pair of M1 Actives contain a total of four power amplifiers. Because of the increased

efficiency of biamplification, these are much louder than a single-channel power

amplifier of the same wattage feeding a passive crossover, as in other designs. New

technology makes it possible to make these high-wattage amplifiers small enough to

fit inside the speaker cabinet, with very little weight or size gain.

Since the M1 Actives are self-powered, DO NOT connect them to

the speaker output of another amplifier (such as a powered mixer

or hi-fi receiver). Connect them only to the line-level outputs of

such devices (+4 dBu nominal, +24 dBu maximum).

Tonally, every effort has been made to emulate the accurate studio sound of Alesis’

Monitor One but with enhanced low bass and high frequency extension. The nominal

frequency response is 50Hz-20KHz ±2dB. (See Figure 1) Additionally, the use of

electronic crossovers within the critical upper midrange frequencies has reduced

phase and time delay anomalies often associated with passive crossovers. By

including discrete woofer and tweeter amplifiers and application-specific electronic

high and low pass crossover filters in the same enclosure the tonal accuracy of the

M1 Active will always remain constant.

The M1 Active’s 6.5” woofer cone is made of proprietary non-woven carbon fiber.

This material is 25% lighter than polypropylene with twice the stiffness for quicker

transient response in the low-to-midbass region and vastly improved midrange

intelligibility (over polypropylene at 1500 Hz). The non-woven carbon fiber cone,