Let the hive mind of Engadget get that for you.
"I am looking for a device that will stream sound from one source to several recipients. For example, I want to stream sound from my TV or stereo to my phone or MP3 player that has radio and Bluetooth capabilities. I have looked into radio transmitters and they seem like a decent choice, but I can't find one that uses external power (USB or from the plug) and I would want one with a transmit range of around 50 meters. Thanks!"
The reason why Canon did not increase optical zoom the the flagship model is because, they have much larger Sensors 1/2.6 sensor vs 1/4 sensor... which is much smaller.
If you noticed the HFS100 lens is much larger than the original HF100 since the sensor size is much larger on the newer model.
IF you have a much larger sensor and wanted 15x optical you most vastly increase the lens size.
That's why canon separated the two various types of models.....