Seriously though, I'm going with a Room Response correction device for frequency response analyzing/calibration/correction. It will have a plug in microphone that sits in your optimal butt site, so that it can first analyze your room response with a built in test tone, and show on screen the response graph with dips and peaks highlighted. One can then dial in a problematic frequency that your room struggles with and correct it.
The 2150 part is mysterious. Probably designates the number of bands that are tuneable - say 50 bands (18Hz - 25KHz) with 21 selectable points, 10 positions each side of the central point = 21 !