That gruff American rocker, Gibson Guitar Corp., has gotten tired of its old life. Instead of just suing copycats and putting out the occasional robot axe, it's now looking to diversify, having spent $52 million on a 54 percent stake in Japanese firm TEAC. The last we heard from TEAC, it was making things like headphones and retro-styled radios, which maybe gives us a hint as to where this new partnership is headed. After all, it's not like the path between music brand and consumer electronics hasn't been trodden to a pulp already.