Sonic Frontiers SFM-160 PRIVATE Operating Manual

OPERATING MANUAL
We at Sonic Frontiers are sure that you will derive many years of listening pleasure with your new
SFM-160 Mono Tube Amplifiers. This brief operating manual contains important information regard-
ing the operation and care of the amplifier, so be sure to read this manual carefully and follow these
simple instructions in order to keep it looking, operating and sounding its best!

VACUUM TUBES

Handling
We suggest that you do not handle the large power tubes with your bare hands or fingers as skin
oils deposited on the glass surface can "leach" through the glass envelope and cause the tube to
become "gassy." In other words, your tube life may be shortened unnecessarily. Use a paper towel
or one of the cotton gloves (supplied) instead. This is also the recommended procedure for handling
the small input tubes. Also, check to be sure that none of the 6DJ8 tube pins are bent when you
install them.
Installation
Whenever you remove or insert the input or power tubes into their sockets, handle them gently and
do not force them into the sockets. Instead, "rock" them slightly as you slowly push them into place,
making sure that they are properly seated. Over-enthusiastic "rocking" may result in the cracking or
breaking off of the keying lug (orientation pin) of the output tube (this is not covered under your 1
year tube warranty).
Recommended Tube Types
Your SFM-160 amplifiers are supplied from the factory with 6DJ8 tubes for the input and driver
stages (installed into the small sockets). You may also use tubes of the following designations:
ECC88, 6922, or 7308/E188CC.
The power tubes are factory supplied matched pair KT99/KT99(a)'s but you may also use
6550/6550A (GOLD AERO or GE, not a CHINESE type) or KT90/KT90(a) types. Although not
essential, we recommend the use of matched pairs or matched quads of power output tubes for low-
est distortion.
NOTE: A true KT88 tube, built to the original British M.O. Valve/Genelex/Gold Lion standards,
may become available in the near future. Until then, the only warranty authorized
KT88 type tube that can be used is the M.O. Valve/Genelex/Gold Lion version - NOT
THE CHINESE version!!!!
\We do not authorize the use of the CHINESE KT88 or 6550 in the SFM-160 amplifiers as the ampli-
fier runs with over 625V dc on the plates. The CHINESE power tubes will likely fail under these
operating conditions; any damage caused to the SFM-160's through the use of these tubes will not
be covered under warranty! Use only the tube types and brands recommended above.
SFM-160 PRIV ATE
MONO TUBE AMPLIFIER