Alesis M1 Active Mk2 manual M1 Active MK2 BI-AMPLIFIERS & Electronic Crossovers

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About the M1 Active Mk2

THE M1 ACTIVE MK2 BI-AMPLIFIERS & ELECTRONIC CROSSOVERS

The M1 Active Mk2 uses a 75W woofer amp and a 25W tweeter amp along with 4th order high and low pass electronic crossover filters centered at 2000Hz. Electronic crossovers, which separate the frequencies before being sent to the amplifiers, have fewer phase problems and less power loss than the traditional passive crossover used after the amplifier. Fourth-order filters are steep (24 dB per octave), which minimizes the interaction between woofer and tweeter near the crossover point. Additionally, the high pass (tweeter) section of this system employs an electronic time alignment circuit. Thus the “launch” of frequencies from both the woofer and the tweeter will originate at exactly the same time.

There are several advantages to using built-in amplifiers and active (electronic) crossovers versus a passive network system, most of which have been previously enumerated in Vance Dickason’s “Loudspeaker Design Cookbook”:

•Lower intermodulation distortion due to amplifier operation over a more narrow bandwidth. Also, clipping caused by low frequency overload is reduced, being limited to only one driver within a two driver system.

•Increased dynamic range. The M1 Active Mk2’s 75W and 25W amplifiers in their bi-amp setup will clip at about the same levels as one 200W amplifier operating into a passive crossover.

•Improved transient response.

•Better amplifier/speaker coupling for woofers.

•Better crossover performance working into a constant impedance load.

•Better subjective sound quality than high level (passive) networks.

•Easier control over driver sensitivity differences.

•Easier manipulation of phase, time delay, resonance, and various kinds of shaping, contouring and equalization.

•Specifically in the case of the M1 Active Mk2, the wide, mid-frequency polar response of the tweeter can be utilized down to a low 2000 Hz thereby mating more cohesively with the 6.5" non-woven carbon fiber (NWCF) woofer. This low crossover point is only possible through the use of a steep, electronic fourth-order (24 dB per octave rolloff) high pass filter.

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M1 Active Reference Manual

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Contents Reference Manual Alesis Contact Information Contents HOW to USE this Manual IntroductionPlease Follow These Precautions When Using this Product Important Safety InstructionsSafety Symbols Used in this Product Contents/Safety Warnings Symboles Utilisés Dans CE Produit Instructions DE Sécurité Importantes FrenchContents/Safety Warnings ICES-003 Issue CE Declaration of Conformity Chapter About the M1 Active MK2Unpacking and Inspection About Powered Monitors Inside Your NEW SpeakersMagnetic Shielding ToneAbout the Drivers M1 Active MK2 BI-AMPLIFIERS & Electronic Crossovers M1 Active MK2 Power Supply Cabinet and Port DesignWHY the Tweeters are Offset About Nearfield Monitoring About the M1 Active Mk2 Speaker Installation Avoiding Reflections in the StudioReflection Prime Listening Position Stereo Nearfield Placement M1 Active MK2 Horizontal Placement Recommendation Vertical Placement Recommendation Playback Check Mode Vertical MID-FIELD Plugging the Ports to Adjust for Room Acoustics Speaker Installation Connections AC Power CableUSE Clean Power GroundingPower Switch Input ConnectionsSetting the Input Level Control 85.0 Avoiding Damage Surround Sound About Surround SoundCenter Speakers in Music Mixes Placement of the Center M1 Active MK2 Speaker in the Studio Placement of Rear Surrounds Recommended positioning of surround speakersSurround Sound Wall Mounting Surround Sound Surround Sound Troubleshooting Troubleshooting IndexService MaintenanceCleaning Obtaining Repair ServiceCustomers outside the USA and Canada Transducers SpecificationsEnclosure Acoustic Section Crossover SectionAmplifier Section GeneralIndex LineAlesis Limited Warranty Please Send in Your Warranty CardM1 Active Reference Manual

M1 Active Mk2 specifications

The Alesis M1 Active Mk2 is a well-regarded studio monitor designed for musicians, producers, and audio engineers seeking high-quality sound reproduction at an accessible price point. With a focus on delivering accurate sound and a balanced performance, the M1 Active Mk2 has become a popular choice for both home studios and professional environments.

One of the standout features of the M1 Active Mk2 is its bi-amplified design. Each speaker is powered by dedicated amplifiers that optimize the performance of the woofer and tweeter separately. This bi-amplification ensures clear and precise sound reproduction across the frequency spectrum. The 6.5-inch low-frequency driver is designed to deliver robust bass response while the 1-inch silk dome tweeter provides smooth high-frequency performance, resulting in a well-rounded audio experience.

The M1 Active Mk2 incorporates advanced technologies to enhance its performance. The monitor features a front-firing bass port that helps to minimize boundary coupling and improves the overall bass response, allowing for placement flexibility within the studio. This design reduces the risk of unwanted resonances caused by proximity to walls, ensuring accurate sound even in challenging acoustic environments.

Another important characteristic of the M1 Active Mk2 is its frequency response, which ranges from 55 Hz to 20 kHz. This wide frequency range makes it suitable for various musical genres and audio applications, enabling users to hear detailed nuances in their mixes. Additionally, the monitor is equipped with a rear-mounted EQ control, allowing users to tailor the sound to their specific acoustic space, mitigating the effects of room acoustics on playback.

Durability and design are also key aspects of the M1 Active Mk2. Its rugged enclosure is built to withstand the rigors of studio use while also providing a sleek and professional appearance. The monitors can be easily positioned on desktop surfaces or mounted on stands, making them versatile for different studio setups.

Overall, the Alesis M1 Active Mk2 stands out as a reliable and affordable option for anyone looking to improve their audio monitoring capabilities. With its bi-amplified design, advanced technologies, and customizable features, this studio monitor delivers impressive sound quality suitable for both amateur and professional recording applications. Whether mixing, mastering, or simply enjoying music, the M1 Active Mk2 is designed to deliver a true-to-source listening experience.
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