FLUENCE is my second project. It is a
preamplifier "With Output Transformer"
(WOT). Probably it is the simplest type of preamp
after the passive one. It is basically composed of one
attenuator, one triode tube, one Output Transformer and
of course power supply. You may notice this simplicity by
examining the schematic
supplied. This topology is not at all known in Hi-End
circles but very well known in Single Ended enthusiasts'
DIY circles. In fact I was inspired by a similar project
appeared in my favorite magazine, Sound
In audio best results are obtained when
simple is matched with quality components
and a well engineered design. In FLUENCE I tried to
combine these three points.
Although in single chassis, the preamp is designed in
true dual mono fashion, with separate power supplies,
separate tubes, etc. The calculations are made to have a
linear response between 20-20000Hz. Choke input, LCLC
type power supply is used and all capacitors are bypassed
Best quality components are used:
- Capacitors: Solen and Hovland
- Resistors: Vishay
- Stepped Attenuator: Sonic Frontiers with Holco
- Inductors: Bartolucci
- OPT: Black Art
- Signal Cables: Kimber AG
The only electrolytic capacitor is on the filament DC
circuit, so no electrolytics on signal path!
WBT silver solder is used and star grounding is
adopted. Chassis and cover materials are all non
magnetic: aluminum, brass and wood.
Finally the result (of course very
I was amazed to hear such big improvement after my ARC
LS2 preamp. The difference is far more than subtle. More
dynamic, much much more three dimensional, fuller in the
mids, more inner detail and much more relaxed. I started
to listen to music rather than the system! It
complemented the NUANCE's both
sonically and visually in a very successful way.
(Pictures: click to