Mackie M1200/M1400 owner manual Term for a sound mixer, usually a large desk-like mixer

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APPENDIX B: Glossary

This Glossary contains brief definitions of many of the audio and electronic terms used in discussions of sound mixing and recording. Many of the terms have other meanings or nu- ances or very rigorous technical definitions which we have sidestepped here because we figure you already have a lot on your mind. If you’d like to get more information, you can call Mix Bookshelf at 1-800-233-9604. We recom- mend the following titles: The Audio Dictionary, by Glenn White; Tech Terms, by Peterson & Oppenheimer; Handbook for Sound Engineers, by Glen Ballou; Mackie Mixer Book by Rudy Trubitt; and Sound Rein- forcement Handbook, by Gary Davis.

balanced

In a classic, balanced audio circuit, the two legs of the circuit (+ and –) are isolated from the circuit ground by exactly the same imped- ance. Additionally, each leg may carry the signal at exactly the same level but with opposite po- larity with respect to ground. In some balanced circuits, only one leg actually carries the signal, but both legs exhibit the same impedance char- acteristics with respect to ground. Balanced input circuits can offer excellent rejection of common-mode noise induced into the line and also make proper (no ground loops) system grounding easier. Usually terminated with 1⁄4" TRS or XLR connectors.

bandwidth

The band of frequencies that pass through a device with a loss of less than 3 dB, expressed in Hertz or in musical octaves. Also see Q.

bus

An electrical connection common to three or more circuits. In mixer design, a bus usually carries signals from a number of inputs to a mixing amplifier, just like a city bus carries people from a number of neighborhoods to their jobs.

channel

A functional path in an audio circuit: an in- put channel, an output channel, a recording channel, the left channel, and so on.

clipping

A cause of severe audio distortion that is the result of excessive gain requiring the peaks of the audio signal to rise above the capabilities of the amplifier circuit. Seen on an oscillo- scope, the audio peaks appear clipped off. To avoid distortion, reduce the system gain in or before the gain stage in which the clipping oc- curs. See also headroom.

console

A term for a sound mixer, usually a large desk-like mixer.

crest factor

The ratio of the peak value to the RMS value. Musical signals can have peaks many times higher than the RMS value. The larger the transient peaks, the larger the crest factor.

dB

See decibel.

dBA

Sound Pressure Level (SPL) measured with an “A” weighting filter.

dBm

A unit of measurement of audio signal level in an electrical circuit, expressed in decibels referenced to 1 milliwatt. The “m” in dBm stands for “milliwatt.” In a circuit with an im- pedance of 600 ohms, this reference (0 dBm) corresponds to a signal voltage of 0.775 VRMS (because 0.775 V across 600 ohms equals 1mw).

dBu

A unit of measurement of audio signal level in an electrical circuit, expressed in decibels referenced to 0.775 VRMS into any impedance. Commonly used to describe signal levels within a modern audio system.

dBv

A unit of measurement equal to the dBu but no longer in use. It was too easy to confuse a dBv with a dBV, to which it is not equivalent.

dBV

A unit of measurement of audio signal level in an electrical circuit, expressed in decibels

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Contents Speaker Outputs Safety Instructions Noise level exposures shown in this chart Manent hearing lossTo suffi Protectors Ciently While thisBe sure the Power switch is off before making connections Quick StartM1200/M1400 Amps can be mounted M1200/M1400 ampsStart dancing, but don’t let the ants out of your pants 1/4 TS connectors are wired Tip = hot + and sleeve = coldThings You Must Remember Application Diagrams Plug for the Connectors SectionGeneral Precautions Considerations Arcane Mysteries IlluminatedContents Application M1400 Main Speakers and Stage Monitors with ONE Amplifier M1200/M1400 Stereo System with Bridged Subwoofer Gain DB for those of you sittin’ there with your calculatorMeters High Current DesignSIG ProtectShort Outputs. Both the Protect and the Short LEDs light upPower Temp StatusPower Cord Fiers first. When poweringSpeaker Outputs If you shut down your System, turn off your ampliAn amp’s signal routing InputBe Aware Should you Choose to terminate your Speaker cables withCold Pin Ring Hot + PinPin Shield LOW CUT Filter ThruConstant Directivity AMP Mode More on Constant Directivity HornsBridge Output ApplicationLimiter NEL 1 inputs onlyHere’s how to configure it Turn the M1200/M1400’s Power off Turn the M1200/M1400’s Power on. WoofSubwoofer Select a rolloff point, via the FrequencySubwoofer Frequency switch setting either 63Hz or 125Hz Rack Mounting AC Power ConsiderationsThermal Considerations Input Wiring Output WiringAC Power Distribution Feet70V Distribution Systems Impedance WireLoad Gauge Warranty Service TroubleshootingMake sure the AMP Mode switch is set to Bridge Are both Gain knobs set to the same position?Mackie Designs RepairWood-Red Rd. NE Woodinville, WA Sound Pressure Level SPL measured with an a weighting filter Term for a sound mixer, usually a large desk-like mixerEMI Frequency See HertzMale counterpart to the phone jack. See above Signal whose level falls between -10 dBu and +30 dBuControl affecting the final output of a TRS Unity gainXLR Connectors ⁄4 TS Phone Plugs and JacksUnbalancing a Line InstrumentsSpeakons Binding PostsBalanced line is a three Balanced LinesBalanced lines offer increased immunity Grounding Here are some guidelinesOptimizing Sound System Levels Don’t use hardware-store light dimmersNext set the master output level fader Dynamic RangeBiamplified System with Active Crossover As a load gets heavier, its impedance in ohms decreases Do the Math OHMS, Loads and SuchOhm speaker load is twice as heavy as a Specifications Indicators Power ConsumptionAC Line Power Limiter SectionFreq Colophon Mackie Designs Inc All Rights Reserved

M1200/M1400 specifications

The Mackie M1200 and M1400 are two prominent power amplifiers that have gained recognition for their reliability, performance, and innovative design in the professional audio field. Engineered for both live sound and studio applications, these amplifiers deliver exceptional sound quality and unmatched power, making them a favorite among audio professionals.

One of the standout features of the M1200 and M1400 is their impressive power output. The M1200 boasts a power output of 1200 watts at 4 ohms, while the M1400 takes it a step further with 1400 watts at 4 ohms. This substantial power allows users to drive a wide range of speakers, making them suitable for various settings, from small clubs to large venues and outdoor events. Furthermore, they excel in providing clean, distortion-free sound even at high volumes.

Both models incorporate Mackie's patented Smart Protect DSP technology. This intelligent thermal and signal protection system helps prevent overheating and ensures that the amplifiers operate within safe limits, enhancing longevity and reliability. The DSP also contributes to superior sound quality, maintaining clarity and detail across different frequency ranges.

Another key feature of the M1200 and M1400 is their rugged construction. Designed for the rigors of touring and live performances, these amplifiers feature a sturdy chassis that withstands the challenges of transport and heavy use. Their efficient heatsink design allows for effective cooling, ensuring the amplifiers remain operational even under demanding conditions.

In terms of connectivity, both models are versatile. They offer XLR and TRS inputs, allowing compatibility with a variety of audio sources. The outputs include Neutrik Speakon connections, providing secure and reliable speaker connections. Additionally, the amplifiers have built-in limiters that help to prevent speaker damage by controlling signal levels.

The user-friendly interface of the M1200 and M1400 includes level control knobs, LED indicators for power and signal, and a comprehensive set of output options. This simplicity ensures that audio engineers can quickly adjust settings to cater to specific acoustic environments, making setup and operation seamless.

In conclusion, the Mackie M1200 and M1400 power amplifiers are remarkable for their powerful performance, durability, and advanced technology. Whether for live sound reinforcement or studio applications, these amplifiers continue to set a standard in audio excellence, proving their worth to sound engineers worldwide.
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