The palmer pmbla active line merger offers professional mono downmixing of stereo signals whilst maintaining audio quality and eliminating ground hum. The line merger has two channels consisting of a stereo input and mono output which are linked together with a combination of a resistor network and superior palmer isolation transformers. The configuration of the palmer line merger makes it ideal for situations such as combining the signals from two mixers keyboards or any other stereo sound source. The sheet steel and aluminium housing also offer robust and long lasting protection for the audio technology packed inside. With switchable 10dbu and an individual input gain pot on each channel the active palmer line merger provides enough gain to deal with even low level signals making it a great option for touring sound engineers dealing with different equipment on a regular basis.