Millennia STT-1 Twin Topology Recording Channel - Manual (Page 6)

STT-1
STT-1 REAR PANEL
(1) MICROPHONE INPUT "MIC INPUT"
Conventional 3-pin female XLR input jacks for use with all standard balanced microphones, both phan-
tom and non-phantom powered. Provides +48 Volts DC Phantom powering via front panel switch. Input
impedance is approximately 6,200 ohms with phantom power switched in. Microphone input is selected
via a front panel rotary switch marked "Source - MIC." Pin 2 is positive polarity. Pin 3 is negative polarity.
Connector contacts are Neutrik Galvatronic gold plated. It is suggested that XLR cable connectors used
with the STT-1 employ identical plating. This input feeds either the vacuum tube gain amplifier (M2)
or solid state gain amplifier (HV-3), with or without transformer coupling, depending on the status of
front panel Twin Topology "TT" and "XFMR" switches. With non-transformer coupling, the maximum
microphone input levels are +3 dBu (vacuum tube) and +14 dBu (solid-state). For reference, a Neumann
U87Ai directly in front of a screaming vocalist (127 dB SPL) will output approximately -6 dBu. (NOTE:
Do not let the front panel "overload indicator" LED fool you. It begins to turn on with a mic preamp
output of +18 dBu. When you first see the red LED turn on dimly, you have 14 dB of output headroom
remaining.)
(2) LINE LEVEL INPUT "LINE INPUT"
Conventional 3-pin female XLR connector for use with balanced line level audio signals. A line level
signal is defined here as nominal +4 dBu operating level. Pin 1 is ground. Pin 2 is positive polarity. Pin
3 is negative polarity. A 1/4" phone jack is wired in parallel with the XLR (Tip=pin 2, Ring=pin 3,
Sleeve=pin 1). Input impedance is approximately 2,200 ohms (x2). Line level input is selected via a front
panel rotary switch marked "Source - LINE." This input feeds either the vacuum tube gain amplifier
(M-2) or solid state gain amplifier (HV-3), with or without transformer coupling, depending on the status
of front panel Twin Topology "TT" and "XFMR" switches. Minimum line input gain is achieved when
amplifier gain controls are set fully counter-clockwise. Maximum line level input level is +30 dBu into
the solid state gain amplifier and +19 dBu into the vacuum tube gain amplifier. Unbalanced "semi-pro"
(-10 dBv) signals should be tried in both the front panel DI input and the line level input — select the
input which sounds best. Line level input XLR connector contacts are Neutrik Galvatronic gold plated. It
is suggested that XLR cable connectors used with the STT-1 employ identical plating.
(3) FRONT END DIRECT OUTPUT "DIRECT OUT"
Conventional three pin male XLR connector providing balanced, line level output directly from the
front-end amplifiers (MIC, LINE, DI). This output is configured before the EQ, Compressor, De-esser,
and main outputs. This direct output is essentially equivalent to the output on an HV-3 micamp and
can be used in addition to the main outputs (below). Pin 1 is ground. Pin 2 is positive polarity. Pin 3 is
negative polarity. This line level output is capable of driving <600 ohm loads and long, high capacitance
cables. Outputs may be configured in an unbalanced configuration by grounding pin 3, or taking pin 2
directly as an unbalanced signal while floating pin 3. In the former configuration, the output is automati-
cally increased by 6 dB. Connector contacts are Neutrik Galvatronic gold plated. It is suggested that XLR
cable connectors used with the STT-1 employ identical plating.
(4) MAIN OUTPUT #1 "MAIN OUT - BAL"
Conventional three pin male XLR connector providing balanced, line level output from all stages of the
STT-1. Can be used simultaneously with all other outputs. Pin 1 is ground. Pin 2 is positive polarity. Pin
3 is negative polarity. This monolithic-based, balanced line level output is capable of driving <600 ohm
loads and long, high capacitance cables and has a maximum output level of +32 dBu. Outputs may be
configured in an unbalanced pin-2-hot configuration by either grounding pin 3, or taking pin 2 directly
as an unbalanced signal while floating pin 3. In the latter configuration, the output is decreased by 6 dB