AEA RPQ2, Owner'S Manual

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11
passive ribbon microphones and some dynamic microphones generally
have a very high impedance, they are sensitive to what is referred to
as “loading.” The lower impedance a mic must drive, the harder the
mic has to work. If the input impedance of a preamp is too close to
the impedance of the microphone, it may exhibit increased distortion,
decreased headroom, poor transient response, and less overall
frequency response. There are no negative consequences to using high
input impedance preamps.
Unleash the full potential of your mics with the RPQ2’s high impedance
circuit. The RPQ2’s default input impedance is 63K Ohms. With
phantom-power engaged, the RPQ2’s Mic Mode input impedance
switches to 10K Ohms. The RPQ2’s NoLoad™ high-input impedance
guarantees the highest sensitivity, bandwidth, transient response, and
clarity from your microphones.
{
SETTING THE GAIN
}
The RPQ2’s JFET circuit design generates up to 81dB of clean and
quiet gain, with extended bandwidth from below 1 Hz to beyond 200
kHz, for dynamic range and transient response that complements all
microphones.
As with any piece of audio equipment, setting and maintaining proper
signal levels are critical to obtaining optimum performance: if the level is
too low, you sacrifice noise performance; if too high, you risk overload
distortion. The AEA RPQ2 provides an easy method for setting and
monitoring the system gain.
Microphone Input Mode
The Mic Gain control (ref. #10) provides from about +13dB to +62dB
of gain for the preamp input stage. The Output Level control (ref. #11)
adds a19dB of output gain, following the CurveShaper™
circuitry, for a total of +81dB of gain.
Start with the Output Level control (ref. #11) pointing at the 0dB
indicator and the Mic Gain control (ref. #10) fully counterclockwise.
Then, with the microphone in position increase the Mic Gain control
until you are happy with the input level in your DAW, console, or tape
machine. On the RPQ2, if the red LED is illuminated too often or too
long, reduce the Mic Gain control one step at a time until it illuminates