Very rare set of mono block tube amps paired with an early Altec 445a tube stereo preamplifier. All units recapped with high quality capacitors and all power supplies have been rebuilt. Amps were also biased. They sound great, very detailed and musical with clear highs and not lacking in bass either. These amps are really powerful, rated at 50 vintage watts so they can drive almost any power hungry speakers with ease. Cosmetically very clean, great examples of the amps and preamp. Can audition for serious buyers. Thanks for looking.