The Holophone Surround Sound Microphone System
Holophone Microphone System- H-1(b)
The
Holophone Microphone System consists of The Elliptical holophone
Head, seven Microphone Elements (either Sennheiser or DPA),
a handgrip and a carrying case. The Holophone terminates
in 7XLR cable ends. These connect either directly to a recording
console for phantom powering, control of gain, etc., or
can be connected to digital recorders which have internal
gain and phantom powering. The Microphones are connected
keeping their channel assignment discrete all the way through
the recording and mixing process, i.e. Channel 1 (Left)
goes to channel 1 of a mixer to channel 1 of a tape deck
to channel 1 of the final deliverable media. 2 goes to channel
2 etc.. Phantom powering for the mics comes from either
a recording console or portable audio recorder with built
in phantom power, directly, in a short cable run situations.
signal level management and other signal manipulations can
be made at this point on the console itself. Alternately
the Holophone's mic-level output can be run into the PCM-7
Preamplifier Control Module through the PCD-7 Preamplifier/Cable
Driver or into a console directly without the PCM-7, using
only the PCD-7 and the Power Supply Unit MPS-1.
The Microphone can be hand-held
using the provided hand grip, or mounted to a boom, mic
stand, etc.
There is alternatively, an
H-1b Model of the head that utilizes lower-sensitivity microphone
elements for increased sound pressure level handling- up
to 140-150db without clipping. This version has also been
designed to be water resistant for use in inclement conditions.
Preamplifier Control Module- PCM-7
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The PCM-7 or Holophone
Preamplifier Control Module, offers several features
unique to surround sound monitoring and microphone
control. Firstly it provides phantom powering directly
to the external PCD-7 microphone preamplifier/cable
driver through a proprietary XLR cable enabling an
easy interface for powering of the seven microphone
elements and external mic preamplifier directly through
a single microphone cable. A 110/240V switch is located
on the rear panel enabling use in international situations.
Seven balanced XLR inputs are provided which directly
relate to the seven Holophone microphone elements
for direct connection to the remotely mounted PCD-7
Microphone preamplifier. Cable runs of up to 1000ft.
can be realized between these two devices with no
appreciable loss of signal.
Input Gain for individual
microphones can be adjusted to suit ambient noise
level from the front panel of the PCM-7 by opening
an easily accessible hidden door. The hiding of these
gain control knobs was done to assure that levels
will not accidentally be tampered with during use.
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When not using all surround
channels discretely in for instance a direct 5.1 channel
broadcast, the front panel also contains adjustments
for the top Holophone channel to be mixed incrementally
into the remaining 5.1 signal. A light comes on when
this feature is exercised notifying the user that
channels are not completely discrete.
For monitoring purposes
the front panel contains a raised Holophone representation
with signal LED's corresponding to the microphone
elements on the Holophone itself. These LED's brighten
incrementally as sound pressure level increases in
the recording environment to give the viewer a very
good visual representation of where sound is originating
from in the recorded soundscape.
A headphone jack is
provided which monitors the holophone output in virtual
surround with level control and a switch to remotely
monitor individual microphone elements. A very useful
feature in the field.
Finally, seven Balanced
Line level outputs, correlating to each of the microphone
channels, are situated on the rear panel for connection
to a console, or directly to a multi-channnel audio
recorder.
A stereo output feature
has been added to the PCM-7 for broadcast in Virtual
Surround which provides a stereo, virtual surround
output from the PCM-7. 5.1 or 6.1 channel Holophone
data is processed and down-mixed to two channels internally.
When monitored in Stereo (headphone jack included)
the result is a two-channel, multi-dimensional soundscape
that can be easily transmitted or recorded without
encoding.
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Microphone Preamplifier/Cable Driver
PCD-7
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PCD-7. The seven channel
Holophone Microphone Pre-amplifier/cable driver has
been designed for use in situations where a long cable
run will be used in broadcasting, larger halls and
permanent installations. Cable runs of up to 1000
feet can be realized without any appreciable loss
in signal quality. Phantom power and -20db pad switches
for the individual channels are included as is a LED
for power on. The Holophone head H-1 is connected
directly to the PCD-7 and a long cable snake can either
be directly connected to a console or to the aforementioned
PCM-7 Preamplifier control module.
The PCD-7 can be floor
mounted or an attachment kit is available for applications
wherein the user would like to attach the unit to
a mic stand or other mounting post etc. in close proximity
to the Holophone Head.
Audio ins and out are
balanced, shielded XLR Connectors.
Powering for the unit comes either directly from the
PCM-7 or from the separate MPS-1 Power supply.
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Microphone
Power Supply MPS-1
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Microphone Power Supply unit. When the PCM-7 or external
console power supply is not being used, for longer cable
runs, the MPS-1 is used to supply phantom power to the
PCD-7 Preamplifier/Cable Driver and ultimately the H-1
Holophone Head. |
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Microphone
Element Options
1. Sennheiser MKE 2-5 omnis
-120db
2. Sennheiser MKE 2-5 Gold High SPL(water resistant) 140db
3. DPA Microphones 4060 134db
