The Nady MM-141 4-channel Mini-Mixer features four Â¼ Inches unbalanced line level inputs with individual volume controls mixed to one Â¼ Inches unbalanced output. Master volume control with integrated Power On/Off switch and Power On LED indicator for ease of use. Other features include: ultra-low distortion, up to 20dB of gain, S/N ratio over 100dB, and a frequency response from 20Hz-20KHz, heavy-duty steel construction with smooth-turn, ultra-stable pots and high-quality jacks and 9VDC powered with either 9V alkaline battery or optional PAD-1 AC/DC external adapter. Nady Systems has been designing, manufacturing, and marketing wireless microphones since 1976. One of the first wireless innovators, Nady has sold millions of wireless systems worldwide, and continues to provide some of the most innovative/ highest performing products on the market at the most competitive prices.