Shares of Steinway Musical Instruments Monday shot up after the 160-year-old piano maker announced it received a superior takeover offer to the pending $438 million deal with Kohlberg and Co. Steinway, the iconic builder of pianos and other musical instruments, said it would accept the second bid from an undisclosed firm unless Kohlberg sweetens its offer. Steinway said \"an affiliate of an investment firm with over $15 billion under management\" stepped forward with a bid of $38 per share, more than the $35 a share offered in July by Kohlberg, a private equity firm. Steinway\'s gains Monday suggested investors expect a bidding war: the shares reached $39.33 in mid-morning trade, up 8.6 percent from Friday\'s close. Steinway \"is prepared to negotiate in good faith with Kohlberg\" if Kohlberg makes a better proposal to that of the unnamed bidder, the company said. Kohlberg has three days to respond. Steinway has said a buyout would help it build its global business without diminishing the legendary quality of its pianos, renowned for their sound and touch. Steinway pianos, under the original Steinway and Sons name, are built in New York and Hamburg, Germany. They have been used by some of the world\'s greatest musicians, including Arthur Rubinstein, Ignacy Paderewski, and Vladimir Horowitz, and are played by current luminaries Evgeny Kissin, Mitsuko Uchida and Lang Lang. Steinway Musical Instruments, Inc. also controls a number of popular brands for other orchestra and band instruments, including Conn, Selmer, Leblanc, King and Yanagisawa.