The SQN-4S Mini MkII is an upgraded version of the SQN-2S mixer which offers line input on all four channels and provides an individual pre-fade output. Input channels CH1 and CH2 are conventional microphone channels offering both attenuation and bass-cut functions. The second channel pair - CH3 and CH4 - offer reduced gain and no power and are thus suitable for use with radio or other self-powered mics. All channels can be routed to left, right or centre. The mixer includes balanced transformerless input and output amplifiers, “virtually unbreakable” analogue level meters, pre-fade listening (on CH4) and a built-in slate microphone.
 
The twin meters offer a range of scaling including PPM, VU and SMPTE and the design also provides the option of M-S matrixing of CH1 and CH2. The limiter is identical to that of the original SQN-4S - as is the low-distortion tone oscillator. Headphone monitoring is provided for a range of sources including left, right, stereo, M-S matrix and L/R sum with a 3-position switch allowing selection of the output, return (from a recorder) or pre-fade from channel 4. In addition to front-panel controls, the mixer includes connection hardware on both side panels and switching functions on the bottom panel. It can be powered from 6 internal AA batteries or externally from a 5V – 18V DC supply.