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Mackie M•800 800-Wat RMS Dual-Differential High-Current Professional Power Amplifier When Mackie introduced their FR Series™ High Current Power Amplifiers some folks went, "Huh? Power amps from Mackie?" After all, they've mostly been known for their precision, studio-quality mixers. Three years later, the "Huh?s have turned into "WOW!s." FR Series amps are everywhere! And with good reason. They've racked up a strong record of reliability in demanding sound reinforcement applications. And tens of thousands of satisfied owners have come to appreciate FR Series sound quality and extra system-enhancing features. Now they've proliferated inside the powered mixers, active sound reinforcement speakers, and industry-standard HR824 near-field studio monitors. FR Series power amps don't pull power out of the ozone or switch on and off a gazillion times a second. They're traditional "lead sled" designs with massive toroid transformers, huge storage capacitors, state-of-the-art output devices and cooling systems that outperform all amps in their price ranges. They deliver enormous amounts of current into extremely low impedances — and they have dynamic power reserves to spare. The reason FR Series amps are so affordable is because of Mackie's huge investment in automated manufacturing technology, not because they cut any corners. Cutting to the chase: FR power amps sound better than their competition when driven into clipping (overload). Since that's how 99 out of every hundred PA systems are usually operated, this is a major point. When an amp clips, you start hearing harmonic distortion. So conventional amps use something called negative feedback to help control clipping distortion. The output section of the amp sends a signal back to earlier stages to "throttle the system down." The trouble is, this "solution" causes its own problem: During clipping, when the amp relies on negative feedback, it electronically "confuses" earlier amp stages, causing them to latch in a clipping mode instead of recovering quickly. Latching causes the amp to sound really awful when pushed too hard — which it inevitably will be. To effectively deal with clipping, an amp must be able to recoup almost instantaneously. That's what is meant by Fast Recovery. FR Series amps use very sparing amounts of negative feedback. Then they use complementary Baker Clamp circuits on the positive and negative voltage amp stages, which prevent the stages from saturating (and latching) during periods of overdrive. An additional transistor senses when the Baker Clamp is active and then activates the FR Series amplifiers' internal limiting circuits. The result is no latching, instant recovery from overdriving the amp, and way better sound. The more heat you can conduct away from an amp's output devices (transistors) the longer they'll last. The better physical contact that can be made between a transistor and its heat exchanger, the more heat can be pulled away and dissipated in the air. All 4 FR Series amplifier models have a mirror-polished heat exchanger that maximizes thermal transfer. This requires hand polishing the exchanger extrusion, but we think it's worth it to achieve better reliability and performance. The exchanger itself is transverse mounted with its air inlet in the middle. Cool room air enters the front of the amp, then travels down 2 short cooling tunnels and exits on the amplifier's sides. This T-Tunnel design provides a more constant thermal gradient than one long cooling tunnel — in other words, 2 short air passages keep all transistors closer to the same temperature instead of getting processively hotter as the air temperature increases down one long exchanger. A big advantage to owning an FR Series amp is that you get important extra features. Features other amp manufacturers make you pay extra for or leave out all together. Variable low cut filters for tighter bass. All PA cabinets only reproduce bass down to a certain point, called the tuned frequency. Below that point, you get audio sludge and potential woofer damage. FR Series variable low cut filters let you feed your system only the frequencies it can handle. You can "dial in" any tuned frequency from 5Hz to 170Hz. All models also include an infrasonic stabilizer circuit that cuts the really low frequencies that cause visible woofer cone flutter. Constant Directivity Horn EQ for smoother treble. To improve high frequency reproduction, many sound systems use constant directivity (CD horns). They improve treble dispersion by more evenly distributing high frequencies. But in doing so, they actually create a frequency "dip" that reduces important frequencies anywhere from 2.5kHz to 5kHz. The old way to compensate for this was a special crossover module (hard to find and usually expensive) or a graphic equalizer (nice try, but the "cure" is worse than the problem). The M 800, M 1400 and M 1400i include separate left and right CD horn EQ adjustments. This 6dB/octave EQ's "knee" position is sweepable from 2kHz to 6kHz — the high end boost is extended so you can add "Air" EQ even if you're not using CD horns. Features: 800 watts @ 4 ohms bridged 550 watts @ 8 ohms bridged 400 + 400 watts @ 2 ohms stereo 275 + 275 watts @ 4 ohms stereo 175 + 175 watts @ 8 ohms stereo Ultra-low-noise/ low-distortion design Fast Recovery circuitry reduces distortion at the edge of clipping and beyond Two 2nd order, 12dB/octave, Bessel low-cut filters with variable frequency from Off to 170Hz help optimize bass output of your sound system Constant directivity horn EQ/Air EQ with variable frequency from 2k to 6kHz and on/off switch Limiter with On/Off switch (decreases distortion that may become present when the M•800 is driven at max levels without affecting overall sound levels) XLR thru outputs 1/4" jacks and 5-way binding post outputs Detented gain controls calibrated in dB & volts Signal present and OL LEDs Channel Status LEDs Easily handles 2-ohm loads all night long Superior T-Design cooling 5-year transferrable Limited Warranty Mackie FR Series Amplifiers Comparison Chart Feature M•800 M•1400 M•1400i M•2600 4-ohm bridge 800W 1400W 1400W 2600W 8-ohm bridge 550W 1000W 1000W 1700W 2-ohm load 400+400W 700+700W 700+700W 1300+1300W 4-ohm load 275+275W 500+500W 500+500W 850+850W Low cut filters yes yes yes yes Limiter circuit yes yes yes yes CD Horn EQ yes yes yes - Subwoofer crossover - 2-position 2-position 3-position XLR pass-through yes yes yes yes 5-way binding posts yes yes yes yes Neutrik® Speakons® - yes - yes 1/4" TS outputs yes - yes - 230V & 100V models yes yes - yes T-Design cooling yes yes yes yes Demand-sensitive fan yes yes yes yes Detented level controls yes yes yes yes LED output display yes yes yes yes Signal present, OL and Channel Status LEDS yes yes yes yes Temp & Short Circuit LEDs yes (Temp LEDs only) yes yes yes
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