The Sony SS-580, high end speakers of the early 1970's. I bought these speakers in Singapore in 1971. They are rated as 25Watt RMS each. Woofer, Tweeter & squawker. If they are boomy the woofer rubber is probably breaking down. Replace with 8ohm 8Watt woofer from Richer Sounds. Frequency response was flat from 60Hz to 25Khz. Bought for £25 a pair in Singapore, but on sale in UK for £50 each in 1971. (My Sony amplifier TA-1010 had twin stereo speaker outputs so needed 4 speakers). Fantastic sound output if using Vinyl (18KHz) or digital (20KHz). Cassette tapes sound boomy because of poor frequency response of tape. (15KHz max). I sold them all as working in 2003 still looking like new.