This,
straight away, is a bargain. Tim de Paravicini,
the head honcho and designer of all things EAR
(formerly Esoteric Audio Research), has for
many years been regarded among the UK’s
foremost tube gurus. He also has had a long-term
involvement with analog recording - everything
from designing custom microphones to actually
mastering LPs. In the EAR 834P we have a product
that clearly benefits from those experiences.
In absolute terms it isn’t cheap, but
that’s relatively inexpensive for the
audiophile phono stage category - and it’s
a bloody import too!
Tube
phono circuits are inherently constrained by
a thermonic device’s noise floor - the
"tube rush" one hears when the volume
is turned up - and which limits the phono gain
to some 40 odd dB, what with RIAA EQ and all.
That’s plenty for the relatively high
output of "moving magnet" cartridges,
but inadequate for the much lower output of
the typical "moving coil" pickups
favored by many audiophiles. Therefore the engineers
designing a phono stage are faced with the dilemma
of increasing the gain without compromising
the sound. Adding an additional tube gain stage
can exacerbate the noise problem, so some develop
"hybrid" designs, typically using
a solid state input stage to amplify the low
voltage output before sending it to the tube
section, thus improving the S/N ratio. But there
is another way, for while the MC cartridge’s
voltage output is low, the current is surprisingly
high. This means a transformer can be used,
trading some of that current for voltage gain,
and keeping the noise level low. The problem,
of course, is that you need a very good transformer.
Audiophiles have been arguing the relative merits
of transformers vs. active gain stages for years,
some finding the transformer more natural sounding,
others finding it limiting dynamics or bandwidth.
While
several companies (notably Ortofon) have offered
outboard transformers as MC step-up devices,
EAR is unusual in incorporating them within
the unit itself, and this choice seems crucial
to the design’s performance/price ratio.
The unit is small (5"x9"x3.5"),
light (around 7 lbs.), and the circuitry is
relatively simple: the power supply only has
to support the main gain section, and the MC
trannies can be simply switched out when MM
cartridges are employed. That is not to suggest
the power supply is inadequate - the circuit
board is essentially split in two (and shielded)
from front to back, and the power supply, toroidal
transformer and all, takes up half the interior
space. On the other side is the audio circuitry,
employing three 12AX7 dual triodes (or equivalent)
and the step-up transformers, housed in small
metal cans almost the size of marshmallows.
Component quality seems very good but not boutique;
the input/output jacks are gold plated, and
the AC cord is standard IEC detachable. The
basic black version I auditioned has two front
panel controls: a "knob" which is
actually an on/off switch, and an Alps pot which
allows the user to match the unit’s output
level to other sources-or drive a power amplifier
directly in dedicated analog systems, i.e.,
without an intermediary preamp. The more expensive,
chrome plated version is functionally identical
except that the level control is omitted. The
black model is also available without level
control, for those who use a preamp and wish
to avoid having an extra volume pot in the signal
path. The MM/MC switch is located on the back
panel, between the RCA in/out jacks. There is
no provision for balanced connections, or for
changing cartridge loading (47Kohms) or capacitance.
The relatively compact chassis gives the EAR
extra flexibility in placement. In many systems
it can be situated adjacent to the turntable,
keeping cabling losses to a minimum.
I
first used the EAR in MM mode, with the Grado
Reference Platinum on the Well Tempered. This
little guy puts out a big sound, notably dynamic,
with excellent rhythmic punch and drive on rock
and jazz. On classical material, it sounded
a bit dark and unsubtle, but promising. Stock
tubes are either EI (Yugoslavia) or Edicron
(the English importer for EI). Time out for
tube-rolling, I figured. Sure enough, things
opened up a bit with a set of UK Gold Aero MC
Phono 12AX7As, but sonics were still a bit threadbare
through the upper mids. Swapping those for the
readily available Sovtek 12AX7WBs was a major
improvement, with much more air and articulation
at HF. I was quite happy with the Sovteks, but
the field was swept by a set of NOS Telefunkens
(not the first time that has happened). The
sound field was markedly richer, fuller, and
natural. Nothing like playing 50s recordings
with 50s tubes.
Thus
encouraged, I decided to try changing the power
cord. I plug any phono stage into an isolated
tap of a Power Wedge line conditioner on general
principles - RFI and AC grunge can be a problem
when you’re talking upwards of 70 dB gain.
But sure enough, a filtered and shielded AC
cord (I had the JPS Labs version in for evaluation)
brought a bit more refinement. Time to switch
over to the van den Hul MC-10 Special and engage
the transformers, Scottie. The differences between
the two setups were obvious through the EAR,
but the overall sonic portrayal was essentially
retained. I was not aware of any significant
reduction of dynamics or tonal aberrations that
would point a finger at the transformers, but
perhaps the presentation was a bit more "civilized".
The sound was silky, detailed, and enticing;
staging was very good on depth, but not quite
as wide a panorama as perhaps could be. But
I quibble. The bottom line here, I feel, is
to go for the basic black model and put the
difference into better tubes and cables if you
can. For reasonable money, you get a true high-end
designer original, and a major payback on playback.
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