Can One Device Stream to Two AirPorts

I bought two AirPort Expresses in order to mimic what Sonos does; namely, streaming music from my device (iPhone SE, iPad and iPod Touch) to my home stereos. I connected the two AirPorts to my two stereos but there seems to be a problem. I cannot play the music from one device through both AirPorts (stereos) at the same time. Both work fine individually, but I cannot do what I intended to do in the first place -- play the same music in two different rooms from one device.

Am I doing something wrong or is it impossible to stream music to more than one AirPort Express at a time?