Introducing the VX2... a new dawn
at CAD. The VX2 features a totally
new approach to tube microphone de-
sign. Each side of the extra large
Optema condenser capsule has its
own independent tube head amp and
output amplifier, including separate
high quality custom output trans-
formers. The dual tube design allows
the head amp tube to be optimized
for low noise, while the output tube
is optimized for driving the trans-
formers and cables. Polar pattern
switching is done at the output of the
microphone rather than at the cap-
sule.
This computer optimized design re-
sults in a noise floor that is lower then
many FET mics, but still has consid-
erable headroom. This is all done
without having to resort to a solid
state output section that could detract
from the true tube sound. The tube
circuit has been optimized for flat
phase response and has a bandwidth
that extends beyond 100KHz. This re-
sults in audibly superior transpar-
ency.
The Optema capsule in the VX2 is
produced in our capsule facility in
Conneaut, Ohio. This new capsule is
extremely large with an actual dia-
phragm diameter of 1 1/4". The high
tension diaphragms are aged, gold
sputtered, and made from the new-
est 3 micron thick high strength poly-
mer film. The other capsule compo-
nents are precision machined brass
and stainless steel. Each capsule is
hand dampened and assembled in a
state of the art clean room facility.
The screen/capsule assembly is eas-
ily removable in the field for use with
optional capsules that will be avail-
able to further increase the versatil-
ity of the VX2 for various recording
applications.
The included power supply for the
VX2 is an analog design utilizing a
toroidal power transformer. Avail-
able soon as an option, is a 24-bit digi-
tal output module for the VX2 with
32 to 96 kHz sampling rates and 120
dB dynamic range.
Dual Valve Condenser Microphone
This Microphone Demands Respect!!*
* For the potentially lethal voltages inside the microphone and power
supply during operation. Never open the microphone housing when
it is connected to the power supply. The power supply has no user
serviceable parts inside. The power supply should only be opened
by a qualified service technician.
ZM-2 Shock Mount
The ZM-2 shock mount is an integral part of the
VX2 microphone and only needs to be removed
to service the microphone or to exchange the cap-
sule/screen assembly with a different type. To
remove the shock mount, unscrew the two
knurled knobs on either side of the microphone
head first, then unscrew the knurled knob in the
back of the microphone.
To replace the shock mount, install the knurled
knob in the back of the microphone FIRST. Then
install the knurled knobs on the sides of the mi-
crophone head.
Power Supply
The VX2PS power supply is set for 117VAC op-
eration at the factory. For 220VAC operation,
change the switch on the rear panel of the supply
to 220V.
Tube Replacement
The tubes that are used in the VX2 have been hand selected for low
noise, and burned in to provide years of service. The VX2 uses 2
different tubes. A 12AX7 (V1) is used for the head-amp and a 12AU7
(V2) for the output section. The actual number that appears on the
tubes in your microphone may be different. These tubes are a very
popular type that are used in many guitar amplifiers and music equip-
ment. However, to insure continued operation within factory specs,
it is recommended that you purchase replacement tubes from CAD.
Contact the CAD sales department.
To gain access to the tubes, first disconnect the microphone from
its power supply. Remove the microphone from the shock mount
by unscrewing the two knurled knobs on either side of the micro-
phone head. Then unscrew the single knurled knob on the back of
the mic near the XLR connector.
To make it easier to remove the housing, place the small toggle
switches in the high-pass, and -8 dB pad position. Remove the switch
bezel by removing the screws on the sides of the bezel. Remove the
mic housing by unscrewing the two screws on the end of the mic
near the XLR connector. Carefully slide the housing off, making
sure the housing clears the small toggle switches.
The tube positions are marked on the printed circuit board near
each tube socket. The 12AX7 is V1, the 12AU7 is V2. Make sure
that the tubes are seated firmly in each socket.
Replace the body by sliding it over the chassis, being careful to
clear the small toggle switches. Center the body over the XLR con-
nector at the end of the chassis. The XLR connector should the hole
at the end of the body part way. Replace the screws in the end of the
housing. Replace the switch bezel and the switch bezel screws. Note:
If the screws in the switch bezel do not align properly, the body may
not be fully seated. Loosen the screws on the body and realign it
first.
Use and Operation
Mount the microphone in the desired location.
Plug the included seven pin cable into the micro-
phone and the power supply. The output of the
microphone is at the 3 pin XLR connector on the
power supply. Use a standard balanced 3 pin XLR
cable to connect the microphone output to the in-
put of your mixer or recorder. Phantom power is
not required. Plug the power supply into your AC
mains supply. Turn the power supply on using the
rocker switch on the right side of the front panel
of the power supply. The LED on the rocker switch
should light. Allow several minutes for the vacuum
tubes in the microphone to warm-up and stabi-
lize. The output level of the VX2 is quite high. It
is recommended that you start with trim control
or input level control turned down on your mixer
or recorder. It is also recommended that you turn
down your input level whenever changing any of
the switch settings on the microphone.
VX2 Switch Functions
Care and Maintenance
The VX2 should be kept in clean dry environment, free from tem-
perature extremes. If the housing becomes soiled, it can be cleaned
with a cloth moistened in isopropyl alcohol.
Removing the Capsule/Screen Assembly
The capsule/screen assembly can be easily removed for use with
optional VX2 condenser capsules. First disconnect the microphone
from the power supply and remove it from the shock mount. (See
above section on ZM-2.) Place the microphone on a soft flat sur-
face to avoid damage to the screen/capsule assembly. Remove the
three screws at the base of the screen assembly. The complete head
will now simply lift off. Use care to avoid damage to the small gold
spring contacts. Place the alternate head on top of the body with the
three gold spring contacts towards the back of the microphone. Re-
place the three screws and secure the microphone in the shock mount.
Contact CAD Sales for price and availability of optional capsule/
screen assemblies.
Pad Off
(0 dB)
Flat
Response
High-Pass
On
-8 dB Pad
Engaged
-16 dB Pad
Engaged
Omnidirectional
Cardioid
Figure 8