Millennia HV-3D Four or Eight Channel Microphone Preamplifier - Manual (Page 6)

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HV-3D
(6) POWER ENTRY "IEC Power Receptacle"
An IEC-type AC line-power receptacle for use with removable cords. Use only the power cord
provided with the HV-3D unit or equivalent U/L approved type SV, SVT, SJ, or SJT AC power
supply cord. Do not defeat the third pin earth ground. If ground lifting is desired, remove the
Earth/Audio Ground Jumper strap (item number 4 above).
HV-3D FRONT PANEL
(1) HIGH RESOLUTION GAIN CONTROL
Detented, 36-position gain control employing a superior quality Grayhill mil-spec gold plated
rotary switch. Switch gain is approximately 1.5 dB per step and is inter-channel matched to
better than 0.08 dB at all settings. After a brief warm-up period, adjustment of this switch is
virtually silent. Two illuminating pushbutton switches (Green and Amber) determine the gain
"range" of the rotary switch. When the pushbutton switches are not depressed (non-illuminated),
the mic preamp gain provided is as printed on the front panel (9.0 dB, 10.5 dB, 12.0 dB, etc..).
When the green pushbutton switch (only) is depressed and illuminated, add 18 dB to the gain
settings as printed on the front panel. When the green and amber switches are both depressed and
illuminated, add 36 dB to the gain settings as printed on the front panel. For example, with both
pushbutton switches depressed and the rotary switch at 12:00 o'clock position, the preamp gain
would be 54 dB (18 + 36).
(2) PHANTOM POWER SELECT SWITCH ("+48V")
Illuminating pushbutton switch which provides phantom power (+48VDC) to the microphone
inserted into that channel. When this switch is depressed (illuminated red), phantom power is
applied simultaneously through dual 6.81k ohm resistors to pins 2 and 3 of the three pin
female XLR input. Use phantom power with condensor and other microphones requiring
traditional phantom supply. CAUTION: Applying phantom power to ribbon microphones
could damage them. Do not use phantom with ribbons, moving coil, and other microphones
which do not require phantom power. Use care, as well, to not insert or extract mic cables
from the HV-3D when phantom power is active.
(3) HIGH VOLTAGE SELECT SWITCH ("+130V") Optional
Illuminating pushbutton switch which selects the four pin XLR input (+130VDC) for B&K (Dan-
ish Pro Audio) high voltage microphones type 4003, 4004, 4009, and 4012. When this switch is
depressed (illuminated amber), the HV-3D receives mic-level audio from the four pin XLR input.
If you are using a B&K (DPA) high voltage microphone with four pin XLR connectors, depress
this switch so that it illuminates. If a conventional microphone is used, do not depress this switch.
The HV-3D will not combine ("mix") both conventional and high voltage microphones on one
channel. NOTE: The HV-3D is designed to provide uninterrupted DC power to B&K (DPA) high
voltage microphones, regardless where this switch is set. Use care that high voltage microphone
cables are not inserted or extracted from the unit when power is on.
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