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Analog Elemental Series
Preference Mic Pre | Introduction
Preference Mic Pre | Control Elements
When recording acoustic instruments or vocals, using a microphone is inevitable. The
actual output level of a microphone is very low and therefore has to be boosted
to studio or line level (0 dB) with a preamplifier. Sometimes signals have to be
boosted by a factor of 2000 or more. As a consequence, the resulting sound
quality provided by the preamp is of paramount importance, so a good micro-
phone preamp that does not overdrive is the definitive requirement in order to
record acoustic instruments or vocals with sufficient dynamics and untainted sound.
The section “Technology” on page 24 explains how the Preference Mic Pre meets these
requirements.
Main Features
• The Preference Mic Pre offers preamplification values of up to +72 dB with lowest noise
operation and a high common mode rejection.
• A VU meter with two modes for average levels (VU) and peak levels (PPM) displays the
output levels.
• A very stable phantom power supply (48 V) is provided to power condenser microphones.
• The polarity of the microphone can be switched with the phase reverse switch.
• A high-pass filter protects against low frequency interferences.
Mic Gain
With the Mic Gain control you can regulate the preamplification of the microphone signal. It
ranges from +18 dB to +72 dB. The input stage can handle input levels of up to 18 dB. The value
set with the Mic Gain control defines the output level equally for both Output 1 and Output 2.
When you set the Mic Gain you have to consider the type of microphone that you are using
(dynamic or condenser microphone) as well as its sensitivity. The sensitivity of a dynamic
microphone is at around 2 mV/Pa whereas the sensitivity of a condenser microphone can be
up to 20 mV/Pa. The result is a difference in output of 20 dB.
You should also consider the sound pressure level of the sound source, the distance of the
microphone to it and the acoustics of the room when you set the preamplification.
About Leveling
Initially you should always ensure to have deactivated the -10 dB button so that the VU meter
displays correct values (see “-10 dB” onthe next page). Now turn up the Mic Gain control until
the VU meter displays maximum levels between 0 dB and +3 dB. At this level you don’t risk
any overdrive when you experience sudden and unexpected peaks in the level of the source.
Always remember that the VU meter only shows average values and that a peak level can be
much higher (up to +10 dB). If necessary, turn on the PPM mode to see the actual peak levels.
Usually levels of around 0 dB and +3 dB are safe. If, however, you experience very high peaks
already at minimum Mic Gain values (i.e. drums, brass instruments), you can activate the PAD
function (see “PAD” on page 24). The input level is now reduced so that you can regulate
Mic Gain again in a useful range.
If you know in advance that the level will be very consistent you can always turn up Mic Gain.
In this case you can activate the -10dB button to have more headroom in the display.