RSPE Audio Solutions, Los Angeles Premier Pro Audio Dealer

The Problem

Long mic level lines, mic splitters, and multiple inputs reduce the sensitivity of the microphone and change its frequency, phase, and transient response. This performance degradation is the result of shifts in impedance, capacitance, and inductance values and is quite audible.

Phantom power on a mic line causes the line itself to become a microphone. Jiggling the line will create audible effects. Having the phantom power source as close as possible to the microphone also reduces the chance of phantom voltage loss within a very long cable run.

Most modern preamplifiers have excellent common mode rejection ratio, often approaching 110dB. If there is common mode signal (noise) built up in cable run and the gain of the preamp is 60dB, the residual common mode noise is only 50dB down. While common mode signal can be present in a short line as well as a long line, there is a higher probability that there will be more common mode signal in the longer line, especially if that line is crossing power and lighting cables and a high RF field.
The Solution
By placing the 1788A close to the mics and controlling it remotely the need for long mic level runs is eliminated.
The noise picked up by long cable runs is no longer boosted at the end of the lines since the preamp gain has already been taken at the input of the line.
By providing 5 outputs ( 3 Digital and 2 Analog ) that are usable simultaneously, the need for splitter boxes is essentially eliminated, although if you DO need additional digital splitting, check out our Model 148 Digital Audio Splitter.