Duende Criatura tube rings considerably reduce microphonics,
distortion and self-oscillation from audio tubes. They
are to be slid around the top part of the tube where
they reduce mechanical vibrations. The listener will
notice improvement of three dimensional picture, a more
controlled bass and a cleaner soundstage.
before mentioned effects are at their best when the
tube ring is sitting around the top part of the tube.
The tube’s ability to radiate heat will be unaffected.
precision-machined Teflon base ring is very dense which
provides excellent damping properties. They can withstand
temperatures of up to 260 degrees, which is much higher
than the operating temperatures of vacuum tubes ranging
from 160 to a maximum of 220 degrees. Duende Criatura
tube rings last indefinitely. A
pure titanium clamp is used to provide the stable pressure
over the Teflon ring to increase the effect. Typically
ohmical, tube circuitry is also sensitive to eddy currents.
Unlike other metal types, Titanium does not cause harmful
Criatura tube rings can be used in pre stages, phase
splitters and output stages. Improvement is recognizable
in non-amplifying and high feedback stages, but sound
improvement is at its optimum in amplifying and low
feedback stages. The Duende Criatura tube rings are
available in different sizes for most tube types. Tube
rings can be easily cleaned in either a dishwasher or
with degreasing soap and hot water.
Paul Candy at 6moons.com, November 2004
all know that vacuum tubes are vulnerable to air and
structure-borne vibrations which can have negative effects
on music playback. Duende Criatura's Tube Rings are
simple Teflon rings that are slit to expand slightly
while slipping over a tube. There's a groove around
the outer portion which contains a Titanium retainer
clamp to ensure a tensioned fit. Lightweight and flexible,
the manufacturer (who makes jewelry in his non-audiophile
life) claims that Titanium will not induce eddy currents
into sensitive tube circuitry. You simply slide these
dampers over the tube and seat them at the top portion
roughly where the getter resides. The Teflon can withstand
temperatures up to 260 degrees and will not melt or
stick to the tubes (hey, it's Teflon!). Nor will it
accumulate any dust or alter color. Providing you position
the ring correctly, it will not affect the tube's ability
to dissipate heat nor alter its operating temperature.
sliding the rings on the input and phase splitter tubes
of my Stingray created immediate benefits. The soundstage
was slightly wider and deeper and gained sharper focus
and greater separation between performers. It was easier
to pick out subtle details in the music to offering
a more involving listening experience. These effects
were immediately audible even during A/B/A comparisons.
The result was magnified yet again when I slipped these
thermionic prophylactics on the Manray's EL84s, with
the added bonus of deeper, more powerful bass and a
greater sense of dynamic agility.
Roy Gregory, Hifi +, issue 28 December 2003
Gregory, editor and publisher of the UK hifi magazine
hifi+ tested the tube rings. This is his conclusion:
with a tubeamp, especially an open chassis model should
investigate these plain looking little rings immediately...
now considered essential as far as I am concerned, and
bring new meaning to the term ‘Simply The Best’."