Summary of the content on the page No. 1
™
REFERENCE MANUAL
©2001 ALESIS CORPORATION
Summary of the content on the page No. 2
Alesis M1 Active Mk2 Reference Manual © Copyright 2001, Alesis Studio Electronics, Inc. All rights reserved. Reproduction in whole or in part is prohibited. “M1 Active Mk2” and “Superport” are trademarks of Alesis Studio Electronics, Inc. ALESIS CONTACT INFORMATION Alesis Studio Electronics, Inc. 1633 26th Street Santa Monica, CA 90404 USA Do not use this address for repair service. Telephone: 800-5-ALESIS (800-525-3747) E-Mail: support@alesis.com Website: http://www.alesis.com
Summary of the content on the page No. 3
Contents/Safety Warnings CONTENTS Introduction 2 IMPORTANT SAFETY INSTRUCTIONS......................................................3 Safety symbols used in this product 3 Instructions de Sécurité Importantes (French) 5 Information to the User for Class A Digital Device (FCC Part 15, Class A) 7 CE Declaration of Conformity 8 ABOUT THE M1 ACTIVE MK2 ...............................................................9 Unpacking and Inspection 9 Inside your new speakers 10 About Nearfield monitoring 15
Summary of the content on the page No. 4
Contents/Safety Warnings INTRODUCTION Thank you for purchasing the Alesis M1 Active Mk2 Biamplified Reference Monitors. To take full advantage of the M1 Active Mk2’s operation, and to enjoy long and trouble-free use, please read this user’s manual carefully. We value any comments you may have about this monitor system, this manual, your Alesis dealer or our factory service. Please take a minute now to fill out your warranty card and tell us what you think. HOW TO USE THIS MANUAL This manual is
Summary of the content on the page No. 5
Contents/Safety Warnings IMPORTANT SAFETY INSTRUCTIONS SAFETY SYMBOLS USED IN THIS PRODUCT This symbol alerts the user that there are important operating and maintenance instructions in the literature accompanying this unit. PLEASE FOLLOW THESE PRECAUTIONS WHEN USING THIS PRODUCT: 1. Read these instructions. 2. Keep these instructions. 3. Heed all warnings. 4. Follow all instructions. 5. Do not use this apparatus near water. 6. Clean only with a damp cloth. Do not spray any liquid cleaner onto
Summary of the content on the page No. 6
Contents/Safety Warnings 10. Protect the power cord from being walked on or pinched, particularly at plugs, convenience receptacles, and the point where they exit from the apparatus. 11. Use only attachments or accessories specified by the manufacturer. 12. Use only with a cart, stand, bracket, rack, or table designed for use with professional audio or music equipment. In any installation, make sure that injury or damage will not result from cables pulling on the apparatus and its mounting.
Summary of the content on the page No. 7
Contents/Safety Warnings INSTRUCTIONS DE SÉCURITÉ IMPORTANTES (FRENCH) SYMBOLES UTILISÉS DANS CE PRODUIT Ce symbole alèrte l’utilisateur qu’il existe des instructions de fonctionnement et de maintenance dans la documentation jointe avec ce produit. Ce symbole avertit l’utilisateur de la présence d’une tension non isolée à l’intérieur de l’appareil pouvant engendrer des chocs électriques. VEUILLEZ SUIVRE CES PRÉCAUTIONS LORS DE L’UTILISATION DE L’APPAREIL: 1. Lisez ces instructions. 2. Gardez ces
Summary of the content on the page No. 8
Contents/Safety Warnings BEIM BENUTZEN DIESES PRODUKTES BEACHTEN SIE SICHERHEITSHINWEISE: (GERMAN) BITTE DIE FOLGENDEN 1. Lesen Sie die Hinweise. 2. Halten Sie sich an die Anleitung. 3. Beachten Sie alle Warnungen. 4. Beachten Sie alle Hinweise. 5. Bringen Sie das Gerät nie mit Wasser in Berührung. 6. Verwenden Sie zur Reinigung nur ein weiches Tuch. Sprühen Sie keine flüssiger Reiniger auf die Oberfläche, dies könnte zur Beschädigung der Vorderseite führen und auch weitere Schäden verursachen
Summary of the content on the page No. 9
Contents/Safety Warnings INFORMATION TO THE USER FOR CLASS A DIGITAL DEVICE (FCC PART 15, CLASS A) This equipment has been tested and found to comply with the limits for a class A digital device pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference when the equipment is operated in a commercial environment. This equipment generates, uses and can radiate radio frequency energy and, if not installed and used in accordance wi
Summary of the content on the page No. 10
Contents/Safety Warnings CE DECLARATION OF CONFORMITY This product conforms to current applicable CE standards for safety. For a detailed description of the standards used, please see the web site Alesis.com. 8 M1 Active Reference Manual
Summary of the content on the page No. 11
About the M1 Active Mk2 CHAPTER 1 ABOUT THE M1 ACTIVE MK2 UNPACKING AND INSPECTION Your M1 Active Mk2 Biamplified Reference Monitors were packed carefully at the factory, and the shipping carton was designed to protect the speakers during shipping. Please retain this container in the highly unlikely event that you need to return the speakers for servicing. The shipping carton should contain the following items: • This instruction manual • M1 Actives with the same serial numbers as shown on the s
Summary of the content on the page No. 12
About the M1 Active Mk2 INSIDE YOUR NEW SPEAKERS ✪ If you’re in a hurry to get started, skip ahead to Chapter 2, “Speaker Installation”, for connection and placement tips. ABOUT POWERED MONITORS The M1 Active Mk2s 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 di
Summary of the content on the page No. 13
About the M1 Active Mk2 TONE Tonally, every effort has been made to create a powered monitor that is as linear as possible, representing a flat frequency response from 50Hz to 20KHz ±2dB. (see p. 21) 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 fi
Summary of the content on the page No. 14
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 th with 4 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 minimize
Summary of the content on the page No. 15
About the M1 Active Mk2 THE M1 ACTIVE MK2 POWER SUPPLY The M1 Active Mk2 employs a regulated switching power supply. This type of supply has previously only been available in amplifiers sold at the very high end of the Pro Audio market. Most power amp customers are familiar with the large transformer and output capacitors in high quality amplifiers. These large components are used to keep the amplifier’s supply rails as close to DC as possible. For traditional supplies, bigger is better. But
Summary of the content on the page No. 16
About the M1 Active Mk2 WHY THE TWEETERS ARE OFFSET The M1 Active Mk2 speakers have been developed as a mirror-imaged pair with dual front mounted ports and an offset tweeter. In some applications, an extremely wide dispersion tweeter, such as used in the M1 Active Mk2, will exhibit response dips if mounted exactly on center. Wave-guide style tweeters, used in other products, purposely limit dispersion and thus can be center mounted. But as hi-end audiophile speaker companies have found, a h
Summary of the content on the page No. 17
About the M1 Active Mk2 ABOUT NEARFIELD MONITORING In the early days of recording, most recording studios used big monitor speakers almost exclusively. Unfortunately, they also required high powered amplifiers and expensive acoustic treatment (often poorly done) of the entire control room. Still, a well-constructed big monitoring system really was impressive to listen to, a fact not overlooked by the studio owners who wanted to impress the record company executives who paid for the big studio'
Summary of the content on the page No. 18
About the M1 Active Mk2 16 M1 Active Reference Manual
Summary of the content on the page No. 19
Speaker Installation CHAPTER 2 SPEAKER INSTALLATION Like any speaker system, your M1 Active Mk2 speakers will work best when properly positioned in a suitable acoustic environment. Achieving proper speaker placement is usually straightforward, but even with nearfield monitors, speaker placement and the acoustics of the listening room itself are too often overlooked and can become significant contributors to an inaccurate and uninspiring monitoring environment. AVOIDING REFLECTIONS IN THE STUDIO
Summary of the content on the page No. 20
Reflection Speaker Installation Direct Path Monitors placed on the console’s meter bridge can directly radiate back onto the console control panel causing a strong delayed reflection at the listening position This kind of speaker placement also couples acoustic energy from the speaker's cabinet more readily into the console's chassis. Both conditions should be reduced by placing the speakers on their own stands acoustically detached from, and slightly behind, the console as shown below. In thi
