WLOL 1330 AM was purchased by MPR in 1980 and carried the KSJN call sign until 1989 when the KNOW letters became available. The AM signal was later spun off into a for-profit subsidiary to help fund the public broadcaster, and was eventually sold off. As of 2005 it goes under the original WLOL name.
In the 1970s, KSJN 91.1 FM and WLOL 99.5 cooperated in an experimental use of quadraphonic stereo, with each station carrying two channels of audio. However, this "quadcast" had some undesirable "ping-pong" effects, much like early stereo broadcasts using the same method did. Somewhat ironically, KNOW currently broadcasts primarily in monaural as its schedule is not music-focused.