With this fa tory sto k tube ompliment, the Komet19 sounds powerful, omplex and detailed.
The distortion is balan ed and harmoni ally ri h. Other brands of audio tubes will operate in
your Komet19. But there are mu h better tubes available than the sto k, modern available
tubes. If you want more info, read on…..
In the Golden Age of tube te hnology ( 1950’s, 60’s and early 70’s ), - virtually all tubes were
manufa tured by European or Ameri an ompanies su h as Mullard, Brimar, Amperex,
Telefunken, Valvo, Tung-Sol, RCA, and others. Unfortunately, all of these ompanies have
dis ontinued audio tube produ tion. Very few of these brands remain available from military
sto k, repair shops, et . These tubes are generally referred to as “ New - Old Stock ” a.k.a.
N.O.S.
The best of the n.o.s. tubes are in every aspe t superior to any urrently modern manufa tured
tube. N.O.S. tubes are very expensive and rapidly disappearing. You may de ide that they are
worth the expenditure. You may not want to use them for pra ti ing, but save them for
re ording and important performan es. The improvement gained by a proper tube sele tion is
quite noti eable in a refined amplifier su h as the Komet. Remember: always pur hase from
a reputable n.o.s. tube dealer. The following ontains brand re ommendations based on our
experien e.
Mull rd / V lvo EL 84 / 6BQ5 The yardsti k used most to measure all EL 84s by. Many
were manufa tured and distributed under different brands or labels. Their internal onstru tion
and soni quality are superior to modern available EL84s. Valvo, Mullard, Brimar, Amperex,
& Telefunkin are ex ellent n.o.s. hoi es. Note: PLEASE CAREFULLY READ the Bi sing
Section on next page of this manual.
ECC 83, 12AX7, 7025, and CV4004 are inter hangeable. There are many brands to hoose
from. The tone and larity an vary between ea h of these tube types and brands. We generally
prefer the European brands: Telefunkens, Brimars, Mullards, Amperex, Phillips Mini Watts,
et . Please keep in kind that ea h amplifier has its own personality that may be omplimented
by a spe ifi brand or sele tion of audio tubes. You may want to resear h for more information
on n.o.s. tubes before you make a pur hasing de ision. Note: when pur hasing, be areful not
to onfuse modern re-issue audio tubes, like the re-issue Mullard, Tung Sol, Genelex, et ., with
original and more expensive n.o.s. audio tubes.
Ple se note: that some new, used, or even n.o.s. preamp tubes an be “ microphonic “. A
mi rophoni tube is a ondition in whi h a tube will absorb me hani al vibration and amplify it
into the audible range. In the worst ase s enario this an mean that the tube will “ feed b ck ”,
or give off a loud, high pit hed squealing noise. Feed ba k an o ur intermittently, even
without an instrument plugged into the input of the amp. This does not mean that the tube(s) are
ompletely unusable. One possible solution you an experiment with is: try reversing V1 to the
V2 phase inverter so ket where mi rophoni s are not as noti eable. The V2 position 12AX7
may be quieter in the V1 position. ( ontinued )
Copyright 2000-2012, Riverfront Musi , L.L.C. d.b.a. KometAmplifi ation. May not be reprodu ed in any form without express written
onsent from Riverfront Musi , L.L.C. d.b.a. KometAmplifi ation.
