Specs & Pricing

The Cutting Edge
the centripetal forces that “pull” the cartridge
through the grooves of an LP and that tend,
simultaneously, to twist it away from its ideal
straight-line course.
Walker’s fixed air-bearing is housed in a large
rectangular brass block—six inches long, two
inches wide, and two inches tall—with a hole,
just a bit larger in diameter than the spindle
that travels through it, running through its
center. Air from the same huge outboard box
that supplies the air-bearing turntable and airsuspension
feet is piped into the hole in the
tonearm-bearing assembly at 50psi through
eight hand-lapped jets in what Walker calls a
“high pressure, medium-flow” arrangement.
Once again, because of the bearing’s stiffness
and the considerably greater length of spindle
that is being “supported” by the air in the
bearing, the effects of torsion are virtually
eliminated.
Bearing size and type are not the only
differences between the two tonearms.
For one thing, there is the way they are
attached—or not—to the turntables. As
with the free-standing modular parts of the
Kuzma Stabi XL ’table, the Air Line tonearm
is itself free-standing, bolted at its far end to
a thirty-one-pound brass pillar that can be
moved up and down
via a thumbscrew.
Kuzma supplies a
digital VTA gauge
that reads the height of the pillar with great
precision, allowing you to experiment with
VTA and return precisely to the same spot on
the gauge. You can also adjust VTA, precisely
and repeatably, via a numbered knob on the
tonearm assembly itself.
Because it is not physically attached to
the ’table, the Air Line tonearm does not
“see” any of the noises or resonances of the
turntable/motor assembly, save as they are
fed back through the stand on which both
Though a bit of a
split decision, to me
the final call isn’t
that close
’table and arm sit. Not being fixed to the
table does, however, make arm setup a bit
more complicated, as the entire freestanding
arm/pillar must be carefully moved, rotated,
and leveled vis-à-vis the platter to make sure
that the tonearm travels at the right height in
a straight line across an LP. (Kuzma supplies
well-written instructions and an alignment
tool that make this process a snap.)
The Walker tonearm is attached to the
’table—sort of. The massive air-bearing block
is fixed on top of two sizeable carbon-fiber
rods that come up through holes in the plinth.
Although the rods are bolted on their bottom
to the plinth’s base, you have to wonder how
much vibration the tonearm might see, given
its own material composition, the mass of
the air bearing and plinth, and the facts that
both tonearm/spindle and platter ride on
air and that the motor is physically isolated
from the ’table. Although not as cool or
convenient as the Kuzma in this regard, the
Walker arm also allows precise repeatability of
VTA adjustments via two knurled knobs on
the tonearm pillar, and because the Walker’s
bearing assembly and arm are fixed in relation
to the platter, arm/cartridge alignment is
somewhat easier.
Another significant difference between the
Kuzma and Walker is the material composition
of their tonearms. The Kuzma uses a stiff,
hollow, conical tube—beautifully machined
from three solid blocks of aluminum and
damped internally—that is welded to the
traveling air bearing. Air is fed to a nipple
on the bearing via flexible tubing that runs
between it and a valve at the supported end of
the tonearm assembly. (A nifty little gauge at
the free end of the tonearm assembly tells you
how much air pressure you’re running through
the bearing.) Air is supplied to the bearing by
a regulated, oil-lubricated, industrial-grade
compressor that filters for dust and moisture.
Because of the occasional loud “spitting”
noises it makes during its duty cycle, the
108 December 2006 The Absolute Sound