CAD Professional Microphones E-100 User's Guide

The Equitek E-100 combines a
dual electret condenser cap­sule design with advanced elec­tronics. Typical FET (field effect
transistor) condenser micro­phones use discrete designs.
This means they use individual
transistors that must be care­fully matched for proper char­acteristics. Even with careful
matching, discrete designs are
inherently nonlinear. Equitek
microphones use a different ap­proach. We do not use any dis­crete FETs. Instead, we use ad­vanced high speed OpAmps
(Operational Amplifiers). These
OpAmps are individually laser
trimmed for optimum perfor­mance and have very high gain.
This allows a large amount of
negative feedback to be used
to significantly reduce any non­linearity. During transients,
these OpAmps may require
more current than typical phan­tom power supplies can deliver.
The extra current demands are
accommodated by our unique
power supply design. Instead
of using phantom power to op­erate the microphone, we use
it to charge a pair of recharge­able batteries. This system cre­ates a huge current reserve for
the microphone's electronics,
yet there is no maintenance in­volved because the micro­phone automatically keeps the
batteries charged during use.
The use of OpAmps is not the
only unique feature of Equitek
microphones. For example, we
also employ servo circuitry to
minimize dc offset and elimi­nate interstage coupling ca­pacitors. The bottom line is we
believe you will find the Equitek
E-100 to have a remarkably
open and clean sound that will
enhance any project.

Bob Eaton
Senior Microphone Engineer

Made with pride in Conneaut,

Ohio U.S.A.

Description

The Equitek E-100 from CAD is a single pattern supercardioid side address microphone designed for recording, broadcast and live
applications. The implementation of high speed, low noise, low distortion electronics makes the Equitek E-100 the ideal candidate for
the most critical applications.

The Equitek E-100 incorporates a number of unique features including:

Servoed head amplifiers.
High SPL Capability (148 dB SPL with pad).
Transformerless balanced output circuits.
Internal power reservoir system that can supply ten times the current available from phantom powering alone.
Dual cantilevered capsule shock isolators.
Remote operation without phantom power using internal batteries.
20 dB non capacitive pad.
Stainless steel internal pop/EMI filter.
Automatic power shut down circuit.

Switch Functions

Power

Hi-Pass

ON = Microphone Power On
OFF = Microphone Power Off (Use this switch position for fastest charg­ing of batteries. See below.)

Left position = Low end roll off below 80 Hz.
Right Position = Flat low end response

0dB = Full gain (Highest Sensitivity)

Pad

-20dB = 20dB Gain reduction (Highest Clipping Level)

Getting Started

The E-100 requires 48 volt phantom power and the internal batteries must be charged for proper operation. Although the internal
batteries were charged at the factory, the batteries will gradually self-discharge if the microphone has been in storage for a long time.
It may be necessary to charge the batteries before initial use. Please see the section below on powering the Equitek E-100.

Caution!

The high gain and wide bandwidth of the E-100 microphone will easily overload the inputs of many professional mixing consoles if
adequate precautions are not taken. This is especially true if the mic is going to be used on percussion or amplified electronic instru­ments. If you have never used this microphone before, we strongly recommend that you initially reduce the system gain by doing one
or more of the following:

 Enable the pad switch on the input of your mixing console.
 Start with the input trim control on your mixing console turned down to a low level.
 Enable the -20 dB pad switch on the E-100 microphone.

Powering the Equitek E-100

The Equitek E-100 is powered by a combination of 48 Volt phantom power and a pair of rechargeable 9 volt batteries. This powering
arrangement overcomes the inherent current limiting associated with most phantom power supplies. The batteries are trickle charged
by the phantom supply. When needed, the batteries provide the extra current necessary during high SPL transients. The microphone
will not function properly without the batteries present. The microphone can be used without phantom power for periods of up to 6
hours provided the batteries are fully charged. Standard 9 volt alkaline batteries can also be used if extended operation is needed when
no phantom power is available.* (Auto power shut off circuit must be disabled for battery operation without phantom power.) The
minimum requirement for the phantom supply is a regulated 48 volts with the capability of supplying at least 8 mA. of current.
Supplies that do not meet this requirement will not allow continuous operation of the microphone. Before initial use, the batteries may
need to be fully charged. Once the batteries have received this initial charge, they should not need to be charged in this manner again,
unless the microphone is unused for a long time. The batteries can be charged by two different means:

 Connect the microphone to a phantom supply and allow the batteries to charge 12 - 14 hours with the mic turned off.

 Remove the batteries from the microphone and charge using a standard battery charger.
* See the section on Auto Power Shut Off. IF USING ALKALINE 9 VOLT BATTERIES, DO NOT APPLY PHANTOM POWER TO
THE MICROPHONE! DOING SO COULD CAUSE PERMANENT DAMAGE TO THE MICROPHONE AND VOID YOUR
WARRANTY!
NOTE: If you normally operate the microphone from phantom power, it is best to leave the microphone power switch in the "on"
position at all times. (The microphone automatically shuts off to conserve battery power when phantom is power removed.)

Auto Power Shut Off Configuration

The following instructions are only important if you plan on using the E-100 without a phantom power supply, such as for remote DAT
recording. The Equitek E-100 incorporates a circuit which shuts the microphone off if phantom power is removed. This is done so that
battery power will be conserved if the user forgets to turn the microphone off. If it is desired to operate the microphone using only the
batteries, this feature must be disabled or the microphone will not function. This is easily done by means of a small movable configu­ration jumper located inside the microphone. To gain access to the inside of the microphone, remove the grille screen by removing the
two top screws. Then remove the switch cover by removing the two screws in the back of the mic behind the switch cover. The jumper
is labeled JP1 and is located near the center of the printed circuit board. (See diagram.) The jumper shorts two of three available pins