Product Overview
180 watts RMS x 5 @ 8 O
255 watts RMS x 5 @ 4 O
225 watts RMS x 2 @ 8 O
350 watts RMS x 2 @ 4 O
Class A/AB circuitry designed by legendary John Curl
Direct coupled - no capacitors or inductors in audio path ensures the cleanest signal
Balanced XLR inputs with discrete circuits
Full power is rated all the way down to 5Hz for unrestricted low-end bass
Custom 1.5 kVA encapsulated toroid power transformer with independent secondary windings for each channel
Hand-matched JFETs for input stage
Hand-matched MOSFETs for driver stage
Beta-matched 15 amp, 60 MHz bipolar output transistors (3 pairs per channel)
100,000 µF power supply filter capacitance
DC Servo and relay protection circuits
Auto turn on by audio signal or 12V trigger
Heavy-duty 24k gold-plated, 5-way speaker terminals
3U chassis with updated cosmetics, rack mountable with HRA3 (sold separately)
Power Output - All 5 Channels Driven
180 watts x 5, 8 O
255 watts x 5, 4 O
Power Output - 2 Channels Driven
225 watts x 2, 8 O
350 watts x 2, 4 O
Power measurements parameters
(with 120VAC, 0.05% THD, RMS continuous power, full audio band): 20 Hz - 20 kHz
Current Capacity
45 amperes peak, per channel
Dynamic Headroom
>1.5dB
Slew Rate
> 130 volts per microsecond
Frequency Response
5 Hz - 100 kHz, +0/-3 dB
20 Hz - 20 kHz, +0/-0.3 dB
Total Harmonic Distortion (THD)
< 0.05 % at full power
< 0.03 % at typical listening levels
IM Distortion
< 0.04 %
TIM
Unmeasurable
Interchannel Crosstalk
> 78 dB at 1 kHz
> 63 dB at 20 kHz
Input Impedance
Unbalanced: 47 kO
Balanced: 94 kO, 47 kO per leg
Input Sensitivity for 28.28 V Output into 8 O
Unbalanced: 1 V
Balanced: 1 V per leg
Total Gain: 29 dB
S/N Ratio
> 112 dB, input shorted, IHF A-weighted
> 102 dB, input shorted, unweighted
Damping Factor
> 1100 at 20 Hz
DC Trigger Requirements
+9 Vdc to +12 Vdc, 5 mA
Audio Trigger Requirements
2 mV - 10 mV
XLR Pin Identification
1 = Ground (Shield)
2 = Positive
3 = Negative (Return)
Power Requirement
Standby: 1 Watt
Idle: 125 Watts
Maximum: 1500 Watts
Dimensions
Depth without cables: 20”
Height without feet: 5.25”
