User Manual

14
Crimson
Mic Gain
The Crimson features two identical microphone preamps. The preamps are discrete, which
means they use single transistors instead of ICs. This allows the preamp to be perfectly opti-
mized for its task — such efforts are usually taken only in the production of high-end preamps.
Use the Mic Gain control to adjust the microphone preamp level. The adjustable volume range
spans from +3 to +60dB. To achieve the best recording level, the -6dB LED should flash from
time to time: you have enough headroom left. If the LED remains always on, it means that the
level is at the brink of overloading — in such cases, you should reduce the Mic Gain value.
The OVL LED indicates the Crimson‘s converter is overloading, which should be strictly
avoided.
IMPORTANT: Read the explanation regarding Input Selection on page 10!
48 V
Use the 48V switch above the Mic Gain knob to activate the 48 Volt phantom power to supply
condenser microphones with an integrated preamp. To work correctly such microphones
require a clean, noiseless voltage, which the Crimson can provide.
VERY IMPORTANT: All condenser microphones with a balanced, floating output, as well as
ribbon microphones, can be used with phantom power.
A microphone with an unbalanced output should only be used without phantom power!
We recommend you to disengage the phantom power for all types of microphones except
condenser microphones.
TO USE THE PHANTOM POWER FOLLOW THESE STEPS:
1. First connect the microphone to the Crimson and then engage the phantom power. Now
you can start to work. Once you are done, disengage the phantom power first.
2. Wait at least ten seconds after disengaging the 48 V phantom power, before you discon-
nect the microphone from the Crimson, to allow for complete discharging — otherwise you
could damage the Crimson‘s input stages!
High-Pass Filter
The high-pass filter passes high-frequency signals but filters out impact noise, rumble and
other unwanted noises below 75 Hz. This first order filter has a 6dB/octave slope, which
means it is soft and goes unnoticed acoustically speaking.
Besides impact noise, other unwanted noises include the ones produced when handling the
microphone.
Application examples: stage miking, speech recordings, vocals and high-pitched instruments
where you are sure that you will not need to record lower-pitched neighboring instruments.
Another aspect you should consider: low frequencies require a lot of energy during conver-
sion, which is another argument for engaging the high-pass filter when the recording allows
for it.
Preamplifier
Control Elements