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Crescendo
Crescendo REVOLUTION 5A4 4 channel Amplifier
SKU: 5A4
$ 779.99
QUICK SPECS
- Best For: SQ Competition Builds | DSP-Based Systems
- Power: 75W x 4 @ 4Ω | 125W x 4 @ 2Ω | 210W x 2 Bridged
- Sound: Class AB High Bias | 0.08% THD | 108dB S/N
- Footprint: 10.6" x 5.9" x 2.4" | 4.6 lbs
Crescendo REVOLUTION 5A4 4 channel Amplifier
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Crescendo Revolution Series
Revolution 5A4 | 4-Channel SQ Amplifier
A pure Class AB High Bias power amplifier built for sound quality competition. No crossovers, no coloration, no shortcuts. Just full-bodied, articulate amplification that separates winning systems from the rest.
Competition-Grade Power, Honestly Rated
The Revolution 5A4 delivers 75 watts per channel at 4 ohms, 125 watts per channel at 2 ohms, and 210 watts per channel bridged at 4 ohms, all rated at 14.4 volts. That is real Class AB High Bias power with the dynamic headroom to render full-bodied vocals and articulate detail at competition judging levels, with a minimum speaker load of 2 ohms.
The numbers behind the power tell the SQ story: 0.08% total harmonic distortion at 1 watt across the audible band, a 108 dB signal-to-noise ratio at rated power, channel separation of 58 dB, and an effective damping factor above 150 from 20 Hz to 20 kHz for tight, controlled driver behavior.
75W x 4RMS at 4 Ohms
125W x 4RMS at 2 Ohms
210W x 2Bridged at 4 Ohms
A Pure Amplifier, Built for DSP Systems
The Revolution 5A4 deliberately omits onboard crossovers and bass boost. In a modern SQ build, filtering, time alignment, and EQ belong in the DSP, and anything the amplifier adds to the signal path is something the processor has to fight. By keeping the signal path pure, the 5A4 hands your DSP exactly what it sent: nothing added, nothing subtracted, amplified with authority.
The high-resolution signal path carries a frequency response of 7 Hz to 40 kHz at -3 dB, preserving the detail and spatial information in high-resolution sources that narrower amplifiers leave behind. Input sensitivity adjusts from 350 mV to 5 V with a 20 kilohm input impedance, matching cleanly to virtually any processor output.
Pair the Revolution 5A4 with a quality DSP such as a Goldhorn processor and the amplifier becomes the foundation of a true competition signal chain: processing handled digitally, power delivered purely.
Class AB High Bias: The SQ Topology
The 5A4 runs a high-bias Class AB output stage, holding the output devices closer to Class A operation than conventional AB designs. The benefit is linearity: lower crossover distortion, better behavior at low listening levels where detail usually disappears, and the refined, dynamic musical character that SQ judges reward.
The brushed grey aluminum chassis measures 270 by 150 by 60 millimeters (10.6 by 5.9 by 2.4 inches) at 2.1 kilograms (4.6 pounds), compact enough to mount cleanly in a show build. Protection covers thermal and short circuit conditions. Note that the 5A4 has no onboard fuse, so external fusing at the battery and near the amplifier is required, exactly as a serious installer would plan anyway.
Topology
Class AB High Bias
Output stage biased toward Class A operation for lower crossover distortion and full detail at low listening levels.
Signal Path
High-Resolution by Design
7 Hz to 40 kHz response preserves every detail in high-resolution sources, with 0.08% THD and 108 dB S/N.
Philosophy
No Crossovers, No Coloration
A pure power amplifier that leaves filtering and EQ to the DSP, where they belong in a modern SQ build.
Control
Damping Factor Above 150
Effective damping from 20 Hz to 20 kHz keeps drivers controlled, for the impactful, precise sound competition demands.
Flexibility
2-Ohm Stable, Bridgeable
125 watts per channel at 2 ohms or 210 watts x 2 bridged at 4 ohms, with input sensitivity from 350 mV to 5 V.
Build
Compact Brushed Aluminum
10.6 by 5.9 by 2.4 inch brushed grey chassis with thermal and short circuit protection, sized for clean show installs.
The Foundation of a Winning System
The Revolution 5A4 does one thing without compromise: amplify. Give it a clean signal from your processor and it delivers the headroom, control, and refinement that put systems on podiums.
| Configuration | 4-Channel Power Amplifier |
| Amplifier Design | Class AB High Bias |
| Power (4 ohms stereo, 14.4V) | 75 watts per channel |
| Power (2 ohms stereo, 14.4V) | 125 watts per channel |
| Power (4 ohms bridged, 14.4V) | 210 watts per channel |
| Minimum Speaker Load | 2 ohms |
| Frequency Response (-3dB) | 7 Hz to 40 kHz |
| THD (1W, 20 Hz to 20 kHz) | 0.08% |
| Signal-to-Noise (rated power) | 108 dB |
| Signal-to-Noise (CEA-2006, 1W) | 89.5 dB |
| Channel Separation (rated power) | 58 dB |
| Effective Damping Factor (20 Hz to 20 kHz) | Greater than 150 |
| Input Sensitivity | 350 mV to 5 V |
| Input Impedance (1 kHz) | 20 kilohms |
| Active Crossover | None (pure amplifier, DSP-ready) |
| Onboard Fuse | None (external fusing required) |
| Protection | Thermal and short circuit |
| Finish | Brushed Grey aluminum |
| Dimensions (W x D x H) | 270 x 150 x 60 mm (10.6" x 5.9" x 2.4") |
| Weight | 2.1 kg (4.6 lbs) |
