Mar 20 1977 JBL Studio 520C 150W Dual 4″ Center Channel Speaker (Black) $180 + Free S/H. Posted on March 20, 1977 by DealFinder Rating: 0 Posted By: djmnunniroy Views: 26 Replies: 0 JBL.com has JBL Studio 520C 150W Dual 4″ Center Channel Speaker (Black) on sale for $ 179.99. Shipping is free. Fatwallet.com Hot Deals