28 1v 20 26 24 22 2v SIG 1&2 – – SPEAKER OUTPUTS + 2 1 + CH CH HOT CH STATUS NORM –3 –6 –9 – 20 OL (MONO BRIDGE) 800 WATTS 4 OHM LOAD MIN. 400 WATTS CH 2 OHMS LOAD MIN. 1.23v (+4dBu) MONO BRIDGE SENSITIVITY 6 12 14 18 3v GAIN/dB 16 –3 –6 –9 – 20 OL 3v BAL/UNBAL INPUT 28 1v 20 2v 26 24 22 1.
CAUTION AVIS RISK OF ELECTRIC SHOCK DO NOT OPEN RISQUE DE CHOC ELECTRIQUE NE PAS OUVRIR CAUTION: TO REDUCE THE RISK OF ELECTRIC SHOCK DO NOT REMOVE COVER (OR BACK) NO USER-SERVICEABLE PARTS INSIDE REFER SERVICING TO QUALIFIED PERSONNEL ATTENTION: POUR EVITER LES RISQUES DE CHOC ELECTRIQUE, NE PAS ENLEVER LE COUVERCLE. AUCUN ENTRETIEN DE PIECES INTERIEURES PAR L'USAGER. CONFIER L'ENTRETIEN AU PERSONNEL QUALIFIE.
Lend Me Your Ears Exposure to extremely high noise levels may cause permanent hearing loss. Individuals vary considerably in susceptibility to noise-induced hearing loss, but nearly everyone will lose some hearing if exposed to sufficiently Duration Per Day Sound Level dBA, In Hours Slow Response intense 8 90 noise for a 6 92 period of 4 95 time. The 3 97 U.S. 2 100 Government’s 1.5 102 Occupa1 105 0.5 110 tional 0.
QUICK START INSTALLATION You can mount the M•800 amp in any standard rack system (see page 18), or place it horizontally on a floor or table. Note: 4 ohms is the minimum impedance you should connect to the amplifier in BRIDGE mode and 2 ohms is the minimum per side for STEREO. If you connect lower impedance speakers, the amplifier may overheat and shutdown. DO NOT BLOCK THE VENTILATION PORTS. The M•800 draws its ventilation air in from the front and out through the side panels.
9. In STEREO and MONO, connect speaker cables to the SPEAKER OUTPUTS , either binding post or 1/4" TS: • The binding posts are wired red = positive (+) and black = negative (–) • The 1/4" TS connectors are wired tip = positive (+) and sleeve = negative (–) 10. In BRIDGE mode, using a single speaker: • The speaker positive (+) connects to CH 1’s red binding post. • The speaker negative (–) connects to CH 2’s red binding post. • Plug nothing into the black posts or the 1/4" speaker output jacks. 11.
CONTENTS ABOUT THIS MANUAL QUICK START ............................................................... 4 APPLICATION DIAGRAMS .............................................. 7 FEATURE DESCRIPTIONS .............................................. 10 GAIN ............................................................. 10 METERS ......................................................... 11 CHANNEL STATUS ............................................ 11 POWER .........................................................
FROM MIXING CONSOLE LEFT MAIN OUT FROM MIXING CONSOLE RIGHT MAIN OUT TYPICAL 35Hz (MONO BRIDGE) 800 WATTS 4 OHM LOAD MIN. 400 WATTS CH 2 OHMS LOAD MIN. STEREO/TYPICAL TYPICAL 35Hz CAUTION RISK OF ELECTRIC SHOCK DO NOT OPEN 120 VAC 60 Hz 1500 WATTS WARNING: TO REDUCE THE RISK OF FIRE OR ELECTRIC SHOCK, DO NOT EXPOSE THIS EQUIPMENT TO RAIN OR MOISTURE. DO NOT REMOVE COVER. NO USER SERVICEABLE PARTS INSIDE. REFER SERVICING TO QUALIFIED PERSONNEL.
FROM EXTERNAL CROSSOVER LOW PASS OUTPUT FROM EXTERNAL CROSSOVER LOW PASS OUTPUT TYPICAL 35Hz (MONO BRIDGE) 800 WATTS 4 OHM LOAD MIN. 400 WATTS CH 2 OHMS LOAD MIN. STEREO/TYPICAL TYPICAL 35Hz CAUTION RISK OF ELECTRIC SHOCK DO NOT OPEN 120 VAC 60 Hz 1500 WATTS WARNING: TO REDUCE THE RISK OF FIRE OR ELECTRIC SHOCK, DO NOT EXPOSE THIS EQUIPMENT TO RAIN OR MOISTURE. DO NOT REMOVE COVER. NO USER SERVICEABLE PARTS INSIDE. REFER SERVICING TO QUALIFIED PERSONNEL.
APPLICATION DIAGRAMS LINE LEVEL OUTPUTS CH 1 CH 2 INPUT GUITAR PREAMPLIFIER/ EFFECTS PROCESSOR WITH STEREO OUTPUTS GOOCH GOOCH TYPICAL 35Hz STEREO/TYPICAL TYPICAL 35Hz CAUTION WARNING: TO REDUCE THE RISK OF FIRE OR ELECTRIC SHOCK, DO NOT EXPOSE THIS EQUIPMENT TO RAIN OR MOISTURE. DO NOT REMOVE COVER. NO USER SERVICEABLE PARTS INSIDE. REFER SERVICING TO QUALIFIED PERSONNEL.
FEATURE DESCRIPTIONS LET’S TWIST A GAIN GAIN/dB These are completely independent volume controls for each channel. Instead of having an arbitary scale, they are carefully calibrated: • The inner ring graphic is labeled in dB, though this indicates the amplifier’s voltage gain, think of it as increasing decibels from off to 28. • The outer ring shows the input sensitivity in volts. This is the amount of voltage required from a mixer to drive the amp to it’s rated power output (225 watts into 4 ohms).
METERS The meters indicate the output level in decibels referenced to the clipping point of the amplifier. The top LED is labeled OL OL OL (short for Overload). If this comes on, the –3 –3 amplifier will start to dis–6 –6 tort, and the audio signals –9 –9 may “clip”. Ideally, the –20, –9, – 20 – 20 –6, and –3 LEDs will light CH STATUS at normal signal levels, 1&2 while the OL LED may NORM HOT blink occasionally during peak moments.
POWER CORD The M•800 is supplied with a detachable power cord. Make sure the power switch is off before firmly attaching the cord to the amplifier. Fit the other end into an AC outlet properly configured for the type of plug on the power cord and for the voltage rating of the amplifier. For current-delivery purposes, the M•800’s voltage source (wall outlet, extension cords, or power strips) must be capable of continuously delivering 12 amps (US model).
If you’re using low impedance loads at high power levels, we recommend that you use the binding post speaker outputs rather than the 1/4" TS jacks. Although 1/4" jacks and plugs are convenient and easy to use, they are not designed to handle high-level currents. Make sure that the amplifier is off before making connections or reconfiguring the signal routing. INPUT The M•800 gives you a choice of inputs — it has XLR as well as 1/4" TRS (Tip-Ring-Sleeve) input jacks.
You can use the THRU jack as an input, if necessary, since it’s wired in parallel with the other input connectors. You can also use the 1/4" TRS INPUT jacks as THRU jacks. Simply connect the 1/4" TRS INPUT jacks on the first amplifier to the TRS 1/4" INPUT jacks on the second amplifier using 3-conductor shielded cables with TRS plugs on both ends. Warning: If you are using a balanced input to the first amp, do not use TS unbalanced connections to feed other amplifiers.
CONSTANT DIRECTIVITY SWITCH If you don’t have constant directivity horns, you can leave this switch OFF. Compression drivers mounted on constantdirectivity horns require compensation in the form of a high-frequency boost, with its “knee” set somewhere between 2kHz and 6kHz. Until now, you’d have to resort to external crossovers or worse yet, graphic EQ modules. Both of these are fraught with limitations, not to mention adding cost, rack space requirements, and complexity to your system.
AMP MODE This three-way switch determines what kind of amplifier you want the M•800 to be (or not to be — what was the question?) The switch alters the input signal routing within the amplifier. Shipped from the factory, it is set to STEREO, correct for about 90% of applications (hence the TYPICAL indicator near it). The switch should only be configured when the amplifer is turned off. STEREO This is the typical setup for amplifying stereo signals.
LIMITER LIMITER ON (TYPICAL). This is the normal configuration with protective limiting. LIMITER OFF is without protective limiting. The limiter is not designed to alter your sound — it’s just there to protect your speakers from the effects of clipping. Its effect is virtually transparent, meaning you probably won’t even notice any audible difference. We recommend that you leave it engaged, hence the TYPICAL label below it.
GENERAL PRECAUTIONS RACK MOUNTING The M•800 amp requires two rack space units (2U = 3.5"). It also requires 16.25" depth inside the rack, including the rear supports. When designing your rack, put the heavier items at the bottom and the lighter items toward the top. Secure the front panel of the amplifier to the front of the rack using four screws with soft washers to prevent scratching the panel.
AC Power Distribution The majority of AC outlets encountered in homes and clubs are served by a 240VAC center-tapped service entrance transformer. This provides two phases of AC power on either side of the center tap at 120V each. In order to minimize ground loops, the safety grounds for all the outlets should be connected to a common (“star”) grounding point, and the distance between the outlets and the common grounding point should be as short as possible.
APPENDIX A: Service Information WARRANTY SERVICE Details concerning Warranty Service are spelled out in the Warranty section on page 27. If you think your amplifier has a problem, please do everything you can to confirm it before calling for service, including reading through the following Troubleshooting section. Doing so might save you from the deprivation of your Mackie amplifier and the associated suffering.
As soon as the music gets loud, the amp shuts down! • Check the M•800’s meters. Be sure that OL is not lighting up frequently or continuously. • Can the amp breathe? The M•800 amps draw their ventilation air in from the front and out through the side panels. They need plenty of fresh air to stay cool. Do not block the ventilation ports. • There may be a dead short somewhere in your speaker setup, or the total impedance of the load is too low. Turn the amp off and rectify that right away.
APPENDIX B: Technical Information SPEAKER IMPEDANCES A speaker’s impedance varies with frequency. For example, it may be 4 ohms at 500Hz, and 6 ohms at 120Hz. What you need to know is the average (or nominal) impedance across the speaker’s frequency range. This will be printed somewhere on the cabinet, or in the specification section of the missing manual. If you’re just dealing with one speaker per channel, then make sure that the average impedance is greater than or equal to 2 ohms.
M•800 SPECIFICATIONS Damping Factor: Maximum Power: 175 watts per channel into 8 ohms 275 watts per channel into 4 ohms 400 watts per channel into 2 ohms 550 watts into 8 ohms bridged 800 watts into 4 ohms bridged Note: Power ratings are specified at 120VAC line voltages. The M•800 power amplifier draws large amounts of current from the AC line with continuous sine wave testing. Accurate measurement of power requires a steady and stable AC supply.
Limiter Section: Physical: Complementary Positive and Negative Peak Detecting Height Width Depth Overall Depth Weight Indicators: 5 meter LEDs per channel –20dB, –9dB, –6dB, –3dB, OL (Overload) TEMP STATUS NORMAL/HOT LEDs Power Consumption: 55 watts at idle 400 watts with musical program fully loaded (4 ohms per side, or 8 ohms bridged) 600 watts with musical program fully loaded (2 ohms per side, or 4 ohms bridged) 550 watts at rated power into 8 ohms (continuous sine wave) 950 watts at rated power in
CH 2 BALANCED LINE INPUT (TRS) THRU (XLR-M) CH 2 BALANCED LINE INPUT (XLR-F) CH 1 BALANCED LINE INPUT (TRS) THRU (XLR-M) CH 1 BALANCED LINE INPUT (XLR-F) FUSE 25 MUTE LAMP POWER SWITCH LOW CUT FILTER FREQ LOW CUT FILTER FREQ THERMAL PROTECT TOROIDAL POWER TRANSFORMER OFF ON CD EQ FREQ OFF ON CD EQ FREQ + 64 VDC – TEMP SENSOR (ON HEATSINK) STEREO MONO BRIDGE MONO BRIDGE STEREO MONO BRIDGE STEREO + 74 VDC – NORM LED 4 SEC DELAY (TURN-ON) LO DCV FAN SPEED CONTROL DC OFFSET P
APPENDIX C: Bi-amping and Tri-amping Most speaker systems in use today are of the two-way or three-way variety. Cone speakers are good at reproducing low and mid-range frequencies, but not high frequencies. Likewise, compression drivers are good at reproducing high frequencies, but definitely not low frequencies.
M•800 LIMITED WARRANTY Please keep your sales receipt in a safe place. A. Mackie warrants all materials, workmanship and proper operation of this FR Series product for a period of three years from the original date of purchase. If you complete the optional questionnaire portion of the Product Registration Card, the warranty will be extended for an additional two years.