POWER OUTPUT: 150 watts per channel continuous from20Hz to 20kHz. 1kHz Total harmonic distortion typically 0.6% at 150 watts,
POWER BANDWIDTH: (-3dB points) 5Hz to 80kHz.
FREQUENCY RESPONSE: (-3dB points at 1 watt) 0.5Hz to 120 kHz.â¨
INPUT SENSITIVITY: 2.0V RMS BAL for rated output. (24 dB Bal gain into 8 ohms.)â¨
INPUT IMPEDANCE: 300K ohms Balanced.
OUTPUT POLARITY: Non-inverting. Balanced input pin 2+ (IEC-268). OUTPUT TAPS: 16 ohms, 8 ohms, 4 ohms.
OUTPUT REGULATION: Approximately 0.6dB 16 ohm load to open circuit (Damping factor approximately 14).
OVERALL NEGATIVE FEEDBACK: 14dB.
SLEW RATE: 13 volts/microsecond.
RISE TIME: 2.0 microseconds.
HUM & NOISE: Less than 0.1mV RMS – 114dB below rated output (IHF weighted, input shorted).
POWER SUPPLY ENERGY STORAGE: Approximately 1040 joules.
WEIGHT: 75lbs.(34.2kg)Net;90lbs.(41kg)Shipping.
Simply put, the REF150 is a breakthrough in stereo power amplification. Replacing the REF110—which was one of the finest and most sought-after modern stereo amplifier was a daunting task, but it has been accomplished. The REF150 offers more power, greater dynamic thrust, a more vivid and resolved presentation, greater finesse, and quieter operation. It is the new benchmark.
When Introduced i, the REF110 power amplifier proved to be one of the most respected and popular stereo power amps ever produced by Audio Research. Now it is superseded by the new REF150, offering more power, more sonic finesse, quieter operation and a more contemporary appearance. Having identical outer dimensions as the REF110, the new REF150 has much more packed into its chassis. Refined front-panel cosmetics reflect the updated look of current-generation models, with silver units having silver handles and silver top cover, while black units have black handles and black cover. (Colors may be mixed to match older models.) Inputs are balanced XLR only, with a 20-amp IEC power connector, 4-8-16 ohm output taps and 12V triggers arrayed on the rear panel.
Under the top cover there are a number of circuit enhancements resulting in stunningly improved performance. First, power-supply energy storage has been doubled to some 1040 joules. All new interstage coupling capacitors using technology and materials first embodied in the Anniversary Edition preamplifier effortlessly link input stage to output stage, which is powered by two matched quads of KT120 output tubes driven by 6H30 twin triodes. Regulation is solid-state and multistage, as in the REF110. Larger, wide-bandwidth output transformers handle the greater output with ease. Power output is rated at 150 WPC into 4-, 8- or 16-ohm speaker loads. Each channel is very quietly fan-cooled using new low-turbulence intake grates, with three selectable fan speeds.
With these internal component improvements, one would logically expect enhanced performance. But it is fair to say you will be shocked by the amount of improvement you hear from the REF150 when compared to its predecessor. Those familiar with the boundary-extending performance of the Anniversary Preamplifier will hear similar characteristics from the REF150. The immediate impression conveys much greater speed, power and control compared to just about any other tube power amplifier you can think of. Bass extension, harmonic delineation and speaker driver control are the best ever to come from an Audio Research tube amplifier – and that is saying something. The REF150 does not drive a loudspeaker so much as it dominates it and brings to life what any competent speaker is truly capable of. Paired with capable frontend components and good cabling, the results are nothing short of a revelation. You will hear inner harmonic structure and dynamic realism that simply were not present before, within an envelope of air and spatial cues that say to you “this is how it actually sounded.” In short, the REF150 amplifies more critical musical information from your preamplifier and source components than you have ever heard before. Prepare to be astonished once again.
