a few things you should know now that you've chosen this rewarding
audio path, and that's what this page is for: To explain the basic
care and feeding of your tube components.
First of all:
Simple: DON'T. Tubes
don't appreciate contact with oils and such from your hands. If
you have to remove or replace a tube, make sure your hands are
clean and, even then, use a tissue to grasp it. Oils and dirt
build up on the glass envelope of the tube, eventually causing
it to run hotter than it should, shortening its life.
Never handle a tube
when it's hot. Before trying to remove a tube, make sure the component
is turned OFF and UNPLUGGED and the tubes have time to cool (usually
just a few minutes).
When removing a tube
from its socket be sure you don't jam it back and forth trying
to pry it out; gentler is better, here. Grip the tube firmly by
the base and pull straight up while gently rocking it a couple
of millimeters from side to side if necessary. You should be able
to remove even the most stubborn tubes in this fashion.
Over time, most tube
pins begin to oxidize, and it behooves you to give them a good
cleaning at least once a year. This can be accomplished with any
number of good contact cleaners (like Kontak) or with good, clean
Isopropyl alcohol (96-99% pure if possible; DON'T use rubbing
alcohol - it contains minerals and oils that tubes don't like).
We recommend using wooden-handled Q-Tips for the actual application
and scrubbing (the paper-handled Q-Tips fall apart under pressure).
If you still have some of the original Tweek Contact Enhancer
around, good for you, but DON'T use it on tube pins. Tweek is
not at its best in high-voltage applications.
Sometimes the easiest
way to re-establish good contact for the pins is simply removing
the tube and putting it back in! This often cuts through the oxidation
and re-makes the contact.
Tube sockets should
be cleaned as well. We recommend (and sell) the tiny socket brushes
designed specifically for the job by DynaClear. Their small size
make it easy to get into the tiniest of sockets. (Again, not to
state the obvious, but please only attempt this while the amp
or preamp is turned OFF and UNPLUGGED!).
Should i leave
my tubed component on all the time?
In 95% of the cases,
no. There are a few components out there (like the Audible Illusions
preamp) that have special circuits that provide a "trickle" voltage
to the tubes, even when the component is turned "off". This does
two things: It prevents the tubes from being "slammed" into operation
when the unit is on, and it also means your "warmup time" to optimum
listening is considerably reduced. Components like the Audible
Illusions preamp are, therefore, "on" even when not "turned on",
but this is a rarity.
In an ideal world,
we'd all use massive Vari-Acs to slowly bring our tube equipment
up to operating voltage. But that's an impractical fantasy.
It's something of
a trade-off. Tubes don't like being turned on and off, but they
also don't like being left on all the time just cooking. So it's
sort of "six of one/ half dozen of the other". We think the tubes
will last longer if not left on continuously, and many components
feature a "soft-start" circuit that helps lessen the shock of
Bottom line: Unless
you really do listen to your system 18 hours a day, turn off your
tube gear and prolong the life of your tubes.
In case you haven't
noticed, tubes get HOT! The single thing that will shorten their
lifespan is making them run even hotter than necessary, so make
sure the unit is installed someplace with good ventilation. This
DOESN'T mean a wooden, designer-type cabinet with closed doors
on the front and a small hole for wires in the back! Open equipment
racks and simple amp stands may not be the last word in stylishness,
but it's a safe bet your tube equipment will last longer and even
sound better with an equipment rack designed for the purpose.
If you HAVE to put it in a cabinet with closable doors, always
leave the doors wide open when the equipment is on. (This is even
a good idea with most solid-state components.)
As to the various
forms of isolation feet, we have a rule of thumb: Sorbothane (or
equivalent material) pucks under tubed preamps, and either cones
(with solid metal tips) or a combination of cones and pucks under
tubed amps. When choosing the soft, Sorbothane types, remember
to provide enough of them to support the component without having
them "squish" down to the point of losing their damping qualities.
In some cases, proper placement of support is critical for best
performance. ASK us about this; every component is different.
There are only a
few things we recommend for improving the performance of tubes
or prolonging their life. High-temperature "O" rings, like those
from Music Reference and 3M, are good for damping the glass envelope
of the tube and cutting down on microphonics (in some circuits
you can actually hear the tube "ring" when the component is tapped).
We can't recommend use of Sorbothane rings for this purpose and
the reason why is simple: THEY MELT! We've seen examples of this,
especially when used in preamps that run hot, where the Sorbothane
melted down the sides of the tube and onto the adjoining parts
and circuit board. Worse yet, once melted, the stuff STAYS melted,
making for one hella mess. We also aren't too fond of devices
that you have to glue to tubes with silicone or such. There are
even some devices that make the tube run HOTTER! Is this a good
thing? Of course not.