Audio Research

 

Founded in 1970, Audio Research is one of the oldest continually operating manufacturers in American audio. Today, Audio Research remains a performance-oriented company by philosophy and design. New product introductions are driven only by genuine advances in technology and performance. The company has grown steadily over the last 40 years, now occupying a 48,000 square-foot, technically-advanced production plant and administrative headquarters in Plymouth, Minnesota, where products are designed, built and serviced by hand.

Audio Research products have demonstrated lasting residual value after purchase. More than a few models have acquired legendary “collector” status and continue to resell for as much or more than what they originally cost. If you want to find out why their products are so sought after, email us or come by Century Stereo for a demonstration today.

LS28 Line Stage Preamplifier

The LS28 line stage is a flexible and intuitive preamplifier. Four balanced and four single-ended inputs, and two sets of both balanced and single-ended outputs, allow maximum connectivity. The straightforward menu allows control of numerous parameters, including input naming, tube hours, auto shutdown, and home theater passthrough. Phase invert and mono are also standard functions. At the heart of the LS28 are four 6H30 vacuum tubes in the analog circuit. While the LS28 is the perfect match for any Audio Research amplifier, it has been designed to work with nearly any amplifier on the market today.

VT80 Foundation Series Power Amplifier

The new VT80 is the much-anticipated amplifier that allows completes the Foundation series system. Combining an enticing new aesthetic with worry-free operation and great audio performance, the VT80 is a vacuum-tube amplifier that will open doors to many new customers.

At the heart of the VT80 are two important new features that have never been offered before by Audio Research. The first is a proprietary auto-bias circuit – simply drop in the tubes and the VT80 will adjust bias for each output tube. The circuit automatically adjusts for tube wear or fluctuations in the power in real time. It will also work for different types of output tubes, including 6550, KT88, KT90, KT120 or KT150. The adjustment range is wide, but matched tubes from Audio Research still provide the highest performance. Finally, an auto-bias circuit that works in real time and does not compromise performance!

The second new feature includes fusing of each output tube. In case of a fault condition in a tube, an easily replaceable fuse will blow, not a resistor. This is what we mean by worry-free operation.

REF 6 Stereo preamplifier

Almost since the inception of the brand, Audio Research has produced some of the finest components for music reproduction; this is especially true with regard to preamplifiers. In 1973, the SP3 was hailed as the best preamplifier available, and this tradition of excellence has continued ever since. The Reference Series from Audio Research was first introduced in 1995 and has been the ultimate representation of performance, musicality and power. The Reference 6 is the latest chapter of our story.

The Reference 6 is not simply a market-driven product, but rather, a solution to a need which arose after the creation of the Reference SE Series amplifiers. According to Warren Gehl, who is responsible for sonic development of all Audio Research products, the new series of Reference amplifiers offer a level of musical and dynamic capability only made apparent when using the flagship, two-chassis Reference 10 preamplifier. Both preamplifiers in the Reference Series need the ability to provide the full benefit of this new sonic landscape. Increasing the tube count to six in the analog section, and advancements in the power supply improved both macro- and microdynamics and lowered distortion.

The Reference 6 also offers better bass control, relaxed purity and more dimensionality. Further improvements include a more grainless presentation, greater transparency, better speed, and more continuity across the musical spectrum. Quite simply, the Reference 6 improves upon its predecessor in every way for a more palpable and immediate musical performance. Numerous elements – transformers, capacitors, wiring – are designs exclusive to Audio Research and the Reference 6.

A completely new chassis has allowed not only a more beautiful aesthetic, but also provides more structural rigidity to assist in the dissipation of electrical and mechanical interferences. Six premium 6H30 tubes are now used in the audio circuit (increased from four tubes in the Reference 5SE) to provide an even quieter background and increased dynamic range. The tube-regulated power supply is also a new design for improved sonics. New circuit boards, circuit designs, and larger power transformer have been implemented to provide robustness and serviceability.

A new volume control with finer step gradation and higher performance completes the system.

REFERENCE 150 SE Stereo Power Amplifier

Simply put, the REF150 SE is a breakthrough in stereo power amplification. Replacing the REF150—which was one of the most respected modern stereo amplifiers—was a daunting task, but it has been accomplished. The REF150 SE offers more power, greater dynamic thrust, a more vivid and resolved presentation, greater finesse, and quieter operation. It is the new benchmark. Having identical outer dimensions as its predecessor, the REF150 SE 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 covers, while black units have black handles and black cover. (Colors may be mixed to match older models.)
The REF150 SE is a fully-balanced design, so its inputs are balanced XLR only. It has 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 incorporated in our Anniversary Edition preamplifier effortlessly link input stage to output stage, which is powered by two matched quads of Russian KT150 output tubes driven by 6H30 twin triodes. There is more than ample multistage solid-state regulation. Output stage coupling is a combination of “ultralinear” and Audio Research’s patented “partially cathode-coupled” topology, which is superior to conventional pentode or triode operation.

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 intakes, with three selectable fan speeds. Internally there is a small LCD display that indicates tube hours.

With all of these changes 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 SE when compared to its predecessor. Those familiar with the boundary-extending performance of the Anniversary Preamplifier will hear similar qualities from the REF150 SE.

The immediate impression conveys much greater speed, power and control compared to 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, regardless of power output – and that is saying something. The REF150 SE does not drive a loudspeaker so much as it dominates it and brings to life what any speaker is truly capable of. Paired with capable front-end 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 let you know that you are hearing everything that the recording has to offer.

In short, the REF150 SE amplifies more critical musical information from your preamplifier and source components than you have ever heard before. Prepare to be astonished once again.