Audio Research Reference 160S Stereo Power Amplifier

Reference Series tube amplification with 140 watts per channel and the flexibility of Triode or Ultralinear operation.

The Audio Research Reference 160S brings much of the technology and performance philosophy of the acclaimed REF160M monoblock amplifiers into a single stereo chassis. Delivering 140 watts per channel, the REF160S combines eight KT150 output tubes, Audio Research's proprietary auto-bias system, switchable Triode and Ultralinear operation, balanced and single-ended inputs, and the unmistakable dual GhostMeters™ of the Reference Series.

Built for demanding high-end two-channel systems, the REF160S combines the dimensionality and harmonic character associated with reference tube amplification with the power, control, bandwidth, and dynamic authority required by modern high-performance loudspeakers.

Derived from the REF160M

The REF160S follows directly from Audio Research's REF160M monoblock amplifier.

Rather than simply placing two conventional tube amplifier channels into one enclosure, Audio Research carried over key technologies developed for the monoblock design, including its output-stage architecture, automatic biasing, tube monitoring, switchable operating modes, and four-layer circuit board.

The result is a true Reference Series stereo amplifier designed to deliver much of the character and capability of the REF160M in a single chassis.

Eight KT150 Output Tubes

The REF160S uses eight KT150 power tubes arranged as four matched pairs, supported by four 6H30 tubes in the gain stage.

In Ultralinear mode, the amplifier produces 140 watts per channel continuously from 20Hz to 20kHz.

Audio Research specifies total harmonic distortion below 0.04% at one watt, demonstrating that this is not simply a powerful tube amplifier—it is engineered for extremely clean operation at the output levels where much everyday listening occurs.

Triode or Ultralinear — Your Choice

One of the REF160S's most compelling features is its ability to switch between Ultralinear and Triode operation.

Ultralinear mode provides the amplifier's full rated output and greater authority for demanding loudspeakers and dynamic musical passages.

Triode operation changes the output-tube configuration for listeners who prefer its different presentation and allows the character of the amplifier to be tailored to the system, loudspeakers, recording, or personal preference.

This makes the REF160S unusually versatile for a reference-class tube power amplifier.

Proprietary Auto-Bias

Owning a reference tube amplifier shouldn't require constant manual adjustment.

Audio Research equips the REF160S with its proprietary automatic bias system, continuously managing the output tubes without requiring the user to manually set bias as the tubes age.

An integrated output-tube monitoring function further simplifies ownership and helps identify tube condition.

The result is considerably easier day-to-day operation without giving up the performance advantages of a sophisticated vacuum-tube output stage.

GhostMeters™

The REF160S is instantly recognizable by its dual GhostMeters™.

Rather than placing conventional meters directly in front of the circuitry, Audio Research creates the appearance of illuminated meters floating transparently in front of the KT150 output tubes.

The design provides visual output indication while leaving the glowing tube complement visible through the front of the amplifier.

It's both functional and one of the defining visual signatures of the modern Audio Research Reference Series.

Balanced and Single-Ended Connectivity

The REF160S supports both balanced and single-ended inputs, making it compatible with a wide range of reference preamplifiers.

Its balanced input requires 2.4V RMS for rated output, with a gain of 25.5dB into 8 ohms. Input impedance is an amplifier-friendly 300kΩ balanced and 100kΩ single-ended.

Dedicated 4-, 8-, and 16-ohm output taps allow the amplifier to be matched appropriately to a broad range of high-performance loudspeakers.

Exceptional Bandwidth

The REF160S isn't designed around the stereotypical soft or bandwidth-limited presentation sometimes associated with tube amplification.

Audio Research specifies a 5Hz–70kHz power bandwidth and an exceptionally wide 0.5Hz–110kHz frequency response at one watt.

That wide-bandwidth architecture contributes to the speed, openness, transient definition, and low-frequency control expected from a modern Audio Research Reference amplifier.

Technical Specifications

Specifications verified against Audio Research's Reference 160S product page.

Audio Research Reference 160S at The Grid HiFi

The Audio Research Reference 160S is built for systems where the power amplifier cannot be the limiting component. Its 140-watt KT150 output stage, REF160M-derived architecture, automatic biasing, switchable Triode and Ultralinear operation, enormous bandwidth, and unmistakable GhostMeters make it a centerpiece for a true reference two-channel system.

The Grid HiFi can help pair the REF160S with the right preamplifier, source components, loudspeakers, power conditioning, cabling, and system setup to realize its full potential.

Considering the Reference 160S? Let's build the system around it.
Contact The Grid HiFi at (713) 218-8120 for availability, system matching, and private audition information.