Hi there,
I started this thread over at Audioholics, and was encouraged (Pogre) to post here as well for additional feedback and sharing with the community.

I have my HT setup with a Marantz AV7705, Emotiva XPA-11, and a bunch of speakers from Ascend Acoustics (front/surrounds) and RSL for Atmos.

The front L/R are the Ascend Sierra Towers, and Center is a Sierra Horizon. These are connected to the mono-blocks of the amp.

I was recently playing some music in stereo mode, not that loud (-8, -6 db tops), and turns out that I busted my midrange woofers. There was the distinct smell of burned rubber, and it the midrange from both towers were done. One completely gave out (no sound at all), while the other was distorted.

Contacted Ascend, and Dina was super nice and Dave pretty responsive via email as well. They suspected a burnt voice coil, and from the smell it does appear to be so, and I bought two replacement midranges.

Dave recommended that I test with some cheaper speakers and there was no hum or pops when on, playing music, or when switching on/off.

The best theory that I've come across (thanks, TLS Guy) is that a power transistor of the amp is starting to fail at a certain temperature, sending a DC offset. Also, that because of the speaker design there's no capacitor in series with the woofer to prevent a DC offset from reaching the woofers. The capacitor is a theory, and I'm waiting on Dave to confirm.

I've reached out to Emotiva about getting the amp tested; waiting on reply.

Any thoughts or feedback from anyone to share?