TL Audio 5052 - Manual (Page 13)

4.3 Line Input.
A line level signal should already be at about the correct operating level, but this may
be checked by monitoring the level with the VU meter set to ‘I/P’. The input gain
should be adjusted until the meter reads about 0VU at normal audio level.
4.4 Instrument Input.
The front panel instrument input socket is suitable for low level sources such as hi
impedance microphones, pick ups or passive guitars, and higher level sources such as
active guitars and keyboards. To cater for this wide variety of sources, the 5052 has
a large amount of gain available, and care should be taken to avoid applying
excessive input gain with a high level source.
4.5 30dB Pad Switch.
Occasionally - when using sensitive condenser microphones - the source signal may
be too loud for the input preamp. In this situation, to avoid any overloading or
distortion of the mic preamp stage, the 30dB pad can be used to reduce the input
gain to a more manageable level. The 30dB pad only applies to the microphone
input.
4.6 90Hz Filter.
The high pass filter switch restricts the low frequency response of the preamp, to
effectively remove rumble or LF noise from the signal. The filter can be useful in
restricting “popping” on vocals or even low frequencies caused by contact with
microphone stands or microphone cables. Popping is an undesirable thump that is
caused by close-miking certain spoken or sung letters, namely “P” or “B”. These
particular letters cause a sudden expulsion of air that can result in an audible thump.
As this thump has a lot of low frequency content the high pass filter can help to
reduce the problem, as can using a pop filter (a device usually made out of nylon
material similar to stockings) suspended in front of the microphone.
4.7 Phase Reverse.
The phase reverse switch allows correction of a phase error, which may have
occurred in microphone wiring or placement. Phase errors can be due to two