Millennia TD-1 Twin Topology Half Rack Recording Channel User Manual
Page 10
TD-
Twin Direct
1
— FRONT PANEL: ROUTING SECTION —
LED INDICATORS Power / SP / OL
Three LEDs (Light Emitting Diodes) which indicate the presence of
DC power (Amber), the presence of a nominal (-25 dBu) audio signal
(Green), and the presence of an audio signal which has exceeded +26
dBu at the balanced line level output (Red). Note that TWIN DIRECT’s
balanced line level output has a maximum output level of +32 dBu. As
such, when the red overload LED turns on, the TD-1 balanced line out-
put is not clipping, but has twice the reserve output voltage headroom
remaining before clipping. The OL LED is set to indicate a maximum
operating level in typical audio environments.
INPUT “TT” TWIN TOPOLOGY Pushbutton Switch
A switch which selects the amplifier topology used to buffer the DI Instru-
ment Input. When switch is depressed and illuminated, the Instrument
Input is routed to an all-discrete, solid-state J-FET (field-effect transistor)
DI buffer amplifier providing musically accurate Millennia audio perfor-
mance. When switch is not depressed and not illuminated, the Instrument
Input is routed to a high voltage twin triode vacuum tube (12AT7) DI
buffer amplifier which can provide a softer, rounder tonal coloration. Note
that Twin Topology input amplifiers are available only on the DI input,
not on the Mic or Line inputs. Mic and Line inputs are routed directly to a
discrete-hybrid solid-state amplifier (see Signal Flow Diagram).
INPUT SELECT Pushbutton Switch
A switch which selects between the Line/Mic and Instrument inputs.
When switch is depressed and illuminated, the Line/Mic Input is selected.
When switch is not depressed and non-illuminated, the Instrument DI
Input is selected.
PAD -20 dB Pushbutton Switch
A switch which attenuates (“pads”) all inputs (balanced or unbalanced) by
-20 dB, thus increasing the maximum input headroom. Pad is engaged
when switch is depressed and illuminated. In most recording or stage ap-
plications, this pad will not be necessary and is included only for unusu-
ally hot sources.
boost and cut. Frequency curve shape is peak/dip type (see “Q”). The
Boost / Cut potentiometer has 21 detent positions for accurate repeat-
ability and session logging. Detents can be removed by the factory upon
customer request.
PARAMETRIC EQ FREQUENCY CONTROL
Conductive plastic rotary potentiometer (2 ea) which sweeps all center
frequencies from 20 Hz to 25 kHz. The low band (LF) sweeps 20 Hz to
250 Hz -or- 200 Hz to 2.5 kHz, depending on the status of Frequency
Range Switch (below). The high band (HF) sweeps 250 Hz to 2.5 kHz
-or- 2.5 kHz to 25 kHz, depending on the status of Frequency Range
Switch (below). This control is optionally available with 21-step detents
for accurate repeatability and logging.
PARAMETRIC EQ FREQ RANGE SELECT Pushbutton Switch “10X”
A switch (2 ea) which selects 1X or 10X parametric frequency multiplier.
When switch is depressed and corresponding LED is illuminated, fre-
quencies as shown on front panel legend are multiplied by 10X. When
switch is not depressed and LED is not illuminated, frequencies are as
shown on front panel legend.
PARAMETRIC EQ QUALITY CONTROL “Q”
Conductive plastic rotary potentiometer (2 ea) which sweeps “Q” (Quality
factor) from 0.4 to 4.0. “Q” is defined as the ratio of the center frequency
to the bandwidth. For example, a filter boost setting with “3 dB down”
points near 100 Hz and 1000 Hz exhibits a “Q” of approximately 0.4. To
achieve a reasonably equivalent response of shelving Eq, simply dial in
the broadest Q (0.4) and boost or cut near a typical frequency extreme
(e.g., 50 Hz or 10 kHz). This control is optionally available with 21-step
detents for accurate repeatability and session logging.
PARAMETRIC EQ IN/OUT SELECT Pushbutton Switch “EQ IN”
A switch which places the single (yes, only one) active Eq amplifier in the
signal path. Minimal signal path Eq topology assures consistently faithful
musical performance.