I bought a new pair in 1977, they may come out even before that, not a rock speaker, but excellant for jazz, vocalist, classical etc. Have jbl l112, dynaco a25, dahlquist dq10, marantz hd770, yamaha high freq is better than the rest. Use power amp of 100wpc or more. Still have and planing to keep. I consider these to be a big sleeper in the yamaha line, not many around and great in a medium to small room. Can also be refoamed if needed.
