I have already purchased a second of this speaker. My intention was to get a speakerphone, which the connection of these two speakers allows. So I use one as a main (remote) and the other as a guest (eavesdropper). When plugging it in, I had a problem with the JBL Compact Connect app on android that I have been using so far. I installed the JBL Pro Connect app which now fully allows me to operate both speakers. First I had to update the firmware on the older box. The connection of the speakers is through the Pass Thru output on the remote box to the audio input on the guest box. So it is a mono output during audio production, i.e. live playing. Stereo can only be achieved through Bluetooth playback of audio files from a phone, mobile, etc.