Audio Research LS27

In exceptional condition, offered for sale is this Audio
Research LS27 hybrid JFET/tube stereo line stage preamplifier with remote
control.  Purchased
new by current owner in 2011 and used for 2995 hours.  Unit has been
unused and stored in climate-controlled environment since 2014.  The two
tubes have not been replaced as there was no degradation in sound.  If
buyer wishes to replace them, they are readily available for $65.00 for
original replacements or higher price for esoteric tubes.  Unit is in exceptional
condition with no marks, blemishes, dents, chips, discoloration or scratches.  Used in a
well ventilated, smoke-free, climate-controlled audio environment with line
conditioners, surge protectors and excellent cables.  Remote control is
also scratch free and like new.  Everything functions as new.  All connectors are bright, tight and wear free.  Interior of unit has minimal dust; unit
was used in HEPA-filtered audio room.  Display is scratch free. 
Includes original power cord, manual, shipping container/inserts.  I will split shipping cost  with inside delivery 50/50 with buyer.  The
sound is pure Audio Research.  If you
take exceptional pride in your equipment you will be pleased to add this
preampflider to your system.

 

Reviews and the owner
manual are available on the web and following is some of Audio Research's
product information:

 

Audio Research LS27 Brochure

The LS27 is our finest LS-series
preamp ever, replacing the venerable LS26 after almost five years. Benefiting
from the latest developments in our Reference series, the LS27 distances itself
from the competition by offering a level of performance not previously
obtainable in its price range.

The LS27 not only offers remarkable
resolution, musicality and dynamic impact, it is our most flexible line-stage
and able to adapt to most any situation. In terms of control options, the LS27
has selectable High / Medium / Low gain settings for each input, BAL / SE input
selection, Left-Right Balance control, Invert (phase), and Stereo / Mono
selection. Tube hours can be monitored, there is a Processor pass-through for
home theater applications, and the display is dimmable with the option of being
turned off. All of the inputs and outputs have balanced XLR and single-ended
RCA connectors, including six pairs of discrete inputs, a processor (unity
gain) input, a monitor loop, and two sets of main outputs. A new microprocessor
controls all functions. The rear panel also includes a 12V trigger and a 15A
IEC connector.

The LS27 is a pure Class-A design
with zero feedback, and the massive power supply is fully regulated. Gain is
provided by twin 6H30 triodes. Multiple circuit changes and refinements account
for greatly improved performance, including bulk power-supply storage that has
been substantially increased, a new power transformer, and costly new output
and bypass coupling capacitors that bring new dynamic life and even more
refinement to the presentation.

The LS27 sounds very much like a
REF5 on a slightly smaller scale, with an organic, lifelike musicality. Like
its big brother, the LS27 combines great resolving power with a tonal richness,
purity and naturalness that is immediately involving. The grain structure is
superfine and electronic artifacts have been banished. Bass impact and control
are also superb, and we believe that the LS27 surpasses the performance of the
REF3 in virtually every way, making it a stunning value.

Look inside the LS27 to see the
exceptional workmanship of this hand-made product. Hear it in your system to
appreciate everything that went into the design and production of this
compelling new preamp.

Specifications

Frequency response

       +0-3dB, 0.2Hz to
160kHz at rated output (Balanced, 200k ohms load)

Distortion (THD)

        Less than .01% at 2V
RMS BAL output

Noise & hum

      1.3uV RMS residual IHF
weighted balanced equivalent input noise with volume at 1 (100 dB below 2V
RMS output).

Gain

     Main Output :
Selectable for each input: 24dB, 18dB, 12dB
     Balanced output (18dB, 12dB, 6dB SE output)
     Record output: 0dB (Processor input: 0dB balanced)

Input impedance

     120K ohms Balanced,
60K ohms SE.

Output impedance

     700 ohms Balanced, 350
ohms SE Main (2). 20K ohms minimum load and 2000pF 
     maximum capacitance

Output polarity

     Non-inverting

Maximum inputs

     Low Gain: 48V RMS BAL,
24V RMS SE
     Medium Gain: 24V RMS BAL, 12V RMS SE
     High Gain: 12V RMS BAL, 6V RMS SE

Rated outputs

     2V RMS 1Hz to 100kHz
into 200K ohm balanced load (maximum balanced output 
     capability is 15V RMS at
less than 0.5% THD at 1kHz)

Power supplies

     Electronically
regulated low and high voltage supplies. Automatic 50 sec. warm- 
     up/brown-out
mute. Line regulation better than .01%.

Tube complement

     (2) 6H30 dual triode.
(Hybrid JFET/tube audio circuit, solid-state power supply).

Power requirements

     105-130VAC 60Hz
(210-260VAC 50/60Hz) 50 watts maximum.

Other

     Inputs (8): Tuner,
Phono, CD, Video, Aux 1, Aux 2, Monitor, Processor (XLR and 
     RCA connectors)
     Outputs (3): 2 Main, 1 Main, 1 Record (XLR and RCA connectors)
     Controls: Rotary volume selector (104 steps) and rotary input selector. Push 
     buttons: Power, Mono, BAL/SE, Proc, Monitor, Mute. Also remote buttons: Display, 
     Bal L, Bal R, Hours, Invert, Gain.

Dimensions

     19" (48 cm) W x
5.25" (13.4 cm) H (standard rack panel) x 13.3" (33.8 cm) 
      D. Handles extend 1.50" (3.8 cm) forward of the front panel.

Weight

     16.3 lbs. (7.4 kg)
Net; 23 lbs. (10.5 kg) Shipping.