The Rolls MX41b is a utility mixer designed to expand the input capability of a constrained physical device. With this mixer, you can route up to four stereo inputs into one stereo output. On one side of the mix, you'll find 1/4" phone and 3.5mm mini inputs with 100-kOhm level fader controls. The rear features a stereo 1/4" TRS output, as well as a stereo 3.5mm output.

If need be, you can reverse the operation: You can route the output of one stereo device to four stereo sources, so long as all controls are set to maximum. Thus, this unit can be a 1-in, 4-out splitter. The MX41b requires no external power, making it a suitable solution for indoor and field use.