low-distortion octal tubes (2-12SN7GT, 2-12J5GT, and 2-6R7G). Name-brand
NOS types are supplied. Assembled unit can be custom wired for user-supplied
complete preamp circuits are incorporated: a classic common cathode-cathode
follower cascade (CF), a shunt-regulated push-pull (SRPP) circuit, and
a passive path. Output and input switching permits any of three sources
to be routed to either of the two active preamp circuits or through the
passive path which allows use of the selector, volume, and individual channel
level controls but with no amplification. A separate record output enables
source switching directly to a tape recorder or CD burner. Optionally,
the record output can be connected as a second output for bi-amplification
or use with a separate headphone amplifier.
wiring is point-to-point with shielded cable and silver-plated Teflon wire
employed in signal paths.
includes a punched, painted chassis, bottom cover plate, detachable line
cord, all parts, tubes, hardware, wire, solder, fuses, knobs. and
an illustrated 35-page instruction manual. Only a few standard tools and
a soldering iron are necessary for construction. High quality components
are used throughout: Xicon 1W carbon film resistors, Solen polypropylene
film capacitors, Clarostat plastic element level control potentiometers,
and Hammond power transformers.
Input resistance: greater than 50K Ohms at 1 kHz. Output resistance:
SRPP: less than 5K Ohms at 1 kHz, CF: less than 700 Ohms at 1 kHz. Voltage
gain (100K load): SRPP: 20 dB at 1 kHz, CF: 25 dB at 1 kHz, Passive: 0
dB at 1 kHz. Frequency response, 100K/50pF load): SRPP: 14Hz–35KHz (–0.5
dB), CF: 17Hz–100KHz (–0.5 dB), Passive (power off): dc–110KHz. Noise (100K
load): SRPP/CF: < 0.5 mV, Passive: < 0.1 mV.