It would be unusual not to have an electrical smell actually. I've often wondered if this smell will disappear as equipment becomes RoHS-compliant.

I am confident the sparks were due to static. I have a similar issue with all of my gear.

14,000 cubic feet. Wow! How does the 600 do on its own in that space? Where do you have the gain set on the back? With the exception of your floor-to-ceiling distance, you probably don't have any room modes in that space.

House of the Rising Sone
Out in the mid or far field
Dedicated mid-woofers are over-rated