A few years ago my off-warranty centre channel speaker failed. It still produced high tones, but no mid to low tones. I put it away and used my stereo without a centre speaker. I've finally decided to have a look, and I've found what looks to be an unsoldered component. It's the bottom of the long black thing, below. The second photo is the view around to the left of the first. The two shaky yellow arrows point to the connection. Will soldering this fix my speaker? What is the long black thing?

