Listen to Internet Radio stations conveniently thru your nearby home stereo system. This transmitter is really designed for close range use, such as listening to portable CD players thru a car stereo radio. The specified range as stated in the instruction manual is 4-6 feet. However, this is somewhat conservative.
Conditions can vary of course.
With most clock radios and receivers placed in MONO mode, this transmitter performs effectively throughout the average size house when the signal is received in mono mode. Just substitute the MK-90 transmitter for a pair of headphones, and then you can easily switch between speakers and wireless transmitter audio output.