by James Leahy
The LS26 is my personal favourite
in the Audio Research pre-amplifier line up for 2006 and my reference
pre-amplifier that I use
in my own system everyday. I believe this model above all others to
give the best value for money against performance return for your dollar. Let me outline the reasons why I
chose this unit to finish off my system's front end.
This is Audio Research's mid line level
pre-amplifier and a direct replacement to the LS25 Mk.II that was first
introduced to the public in 2001. To many it is a complete new look from
the past models, sporting a new fluorescent display that alerts the user to all
input settings, attenuation settings, volume level, Bal/SE input,
balance position, mono/stereo, invert, gain, tube hours and the like.
are two 6H30 tubes used in the gain stage like in it's predecessor the
LS25 Mk.II, but that is where the similarities end. The two
pre-amplifiers use such totally different circuits that the LS25 Mk.II
cannot even be factory up-graded to the LS26.
The build quality has been improved even
further if that was at all possible. The attention to detail is truly
worthy of reference grade component status and would flatter the
appearance of any system. The LS26 is the standard size of the old LS25 Mk.II. The benefits of the fluorescent display have been very popular
with many of my customers already and it has no less than eight
brightness settings plus an off position that illuminates for a period
of ten seconds when any button is depressed either on the remote
controller or on the units front face. The preferred user presets are
furthermore remembered by the LS26 even when the power is disconnected.
Now that's one smart unit.
More new enhancements are self evident in the up-graded
volume control that features 104 step graduations. The power supply is
one of the beefiest I have ever encountered in a pre-amplifier of this
type and is not just massive but fully regulated with a claimed
frequency response of up to a whooping 160kHz. Capacitors in the power
supply are a barrage of Nichicon spec units of the highest quality. Those out there familiar
with valve amplifiers and pre-amplifiers know the critical nature of the
transformer in the performance equation when it comes to the final sound
signature of the product in question. More so than any other component
in the circuit does this make or break the overall coherence of synergy
between air and space. The major difference for me between the LS26 and
the REF3 is the latter has all tube regulation in the power supply when
the LS26 does not.
The LS26 also carries a full array of Balanced
& SE inputs for every input that would be of great value to those who
have components with Balanced outputs. You would want to use this method
of connection as the LS26 is of a fully Balanced design. The LS26 even has
the control to select Balanced or SE for each input thus optimizing the
circuit for that particular input and rendering the unused input defunct
as to avoid any possible cross contamination between input circuits. So I am told by Audio Research.
sight of the LS26's back panel looks like a fully functional commercial
grade controller with every conceivable requirement provided for. There
is two pre-amplifier outputs for those interested in bi-amplifying their
loudspeakers. Also included is a Processor input for those who wish to
use the LS26 in a Home Theatre system and use an external processor to
control the system. There is the obligatory 'Monitor In' and 'Record
Outputs' for a tape deck connection given also. You have the standard
IEC detachable power cord socket given also which can prove to be handy
for those who prefer to tune their system's sound via different power
leads. Audio Research have given a +12VDC output trigger also on the
back panel to be used for remote control 'power on' operation of their
power amplifiers via remote control when the LS26 is switched on.
There are 3 attenuation levels for each input,
namely 'Low', 'Med' and 'Hi' that can be assigned via the remote to help match the levels between varying source
components. This is a more useful feature than it sounds and one that I
am glad they kept from the previous model.
The remote control unit of the LS26 is elegant
yet fully functional with all functions able to be controlled from your
listening chair. I am thrilled to say that for the first time to my
knowledge Audio Research have included discrete input selector buttons
so the user no longer has to toggle through from one side to the other
just to select a desired component of choice. Kudos, Audio
Connecting this pre-amplifier to my system was
a matter of great anticipation for it has been over 5 long years since
the LS25 Mk.II was first released. What would it sound like, what
improvements could we expect? Judging from my system's sonic performance
over the last few days from this review for those of you who might still
be unaware the pre-amplifiers importance in the musical preproduction
chain is of supreme importance. In this review from trying 4 different
Audio Research pre-amplifiers in my system the differences in overall
coloration, presentation, image size, soundstage width and sonic drive,
have never been more obvious. Let me outline briefly my findings.
Compared to the Audio Research LS15 the LS26's sound
had much more focus and control leading to an improved image that is not
forward nor is it laid back per se. The LS15 to me sounded very 'old
time' and unexciting to listen to although it did the job without any
obvious flaws other than the one mentioned. I had just replaced the
output tubes in this unit with four factory specification Electro
Harmonics 6922's before this testing, which did improve the sound from
how it was but my not enough to change my mind and alter my opinion of
the unit. The LS15's sound image was always a little fluffy and hazy for
my taste with a lack of drive.
On the other hand in stark contrast, the LS26's soundstage is constantly moving the
depth of the room with vocals and instrumental cues on the same track
being able to be detected over the length of the room from one's seating
position. This is indeed very rare and I have not encounter this
attribute too many times before. More is the pity. It brings much more
colour and enjoyment to the music than a typically two dimensional
presentation that is namely only black & white in comparison. Dynamics
were head and shoulders above
what the LS15 could produce with marvellous drive and slam being felt
through one's chest without any traces of harsh or unflattering grit in
the mid range or treble. This attribute is very hard to come across. It
is in these two key areas that I feel it betters the old LS25 Mk.II by a
As a special side note I would like to make
readers aware of a 'trick' I like to use (that I have tested with the
LS26, LS25 and SP15) that changes the shape of the sound stage. Audio
Research advise that the Gain function is to be used in combination with
the volume control to equalize different source levels. I however have
found that the LS26 and other's output is considerable fuller and richer
if one uses the lowest possible gain setting and increases the volume
control to compensate. The character changes from a flatter presentation
to a more developed multi layered Technicolor vision of splendour. Try it
yourself and tell me what you think.
Compared to the old Audio Research SP15, the LS26
showed more liquidity and realism in the lower octaves where the SP15
could be a touch dry and gritty depending on how revealing the rest of
your system is. The differences were small but there
were there none the less. The greater range of differences could be heard in the
speed of presentation that the LS26 had over anything else I put it up
against. It was like when the sound ceased there was zero overhang and
the instant the sound started you could feel the rhythm beat through
you like there was nothing between you and the music as in a live
performance. Where as
before I felt there was a slight gap always present and you were left to
anticipate the next beat before you would hear it.
Interestingly I have always felt that every
system has a correct volume where everything sounds 'right'. In mostly
every system when the level was increased the soundstage would break-up or become nastily
gritty. Conversely when the volume was decreased beyond what I will call
the 'perfect position' the soundstage would implode inwards upon itself
and the dynamics would be lost. Before the LS26 my system like so many
others I have heard that suffered from this problem. But now no longer had a narrow sweet spot anymore
the volume was increased the sound was just louder and when turned down
the volume was simply lower but with the same overall character to it.
There was no loss of detail!
Playing my current favourite vinyl demo album at
the moment while reviewing all of the pre-amplifiers mentioned in this
review was Elton John's - 'Honky Chateau' album (MCA Records, 1972).
The soundstage with the LS26 was totally engrossing in it's surrounding
properties and being able to draw you into the middle of the performance
rather then leaving you sitting on a bucket outside the gates made me
believe that this was indeed something quite special. The
tonality was spot on and timbre of the strings sounded pure rather than
slightly veiled as with the others. This coupled with the immense drive
this pre-amplifier had and correct timing with the speed of delivery
gave a first class performance that would satisfy even the most
stringent of listeners.
As a small side note for those interested, the
Audio Research SP16 was not in the same class sonically as either of the
afore mentioned units and at it's substantially lower price point it is
unfair to compare it. So I won't. Suffice to say the overall and
combined differences heard between all of their Audio Research
pre-amplifiers was not small. All tests were completed using the
balanced outputs and after a warm-up period of 60 minutes was given.
Audio Research claim that the new LS26 indeed
is such a sonic break through that it inevitably outperforms their
previous world reference standard, being the Audio Research REF2 Mk.II.
I have no doubt that this is true although I have not directly compared
the two in a side by side test. I have however heard both.
The LS26 is
nearly half the price of the old flagship model that it surpasses
through trickle down technology directly handed down from the newly
developed Audio Research REF3 circuitry. Put in simply terms the LS26 represents
the bargain of the year in High-End audio circles when today you can buy
one new for nearly half the cost of last years top of the range Reference 2 Mk.II.
LS26 has far better sonic qualities too and with the money saved you
could get yourself out of trouble with the other half after buying such
a exclusive unit. If not, I know which one I'd keep. Now that is a deal worth having.
Associated review Equipment
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Audio Research PH5
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Ortofon MC Jubilee