Vintage 1970s YAMAHA NS-690 Speakers Pair Floor Standing Audiophile Speakers HiFi. Great vintage pair of speakers and highly sought after. Tested and the tweeters are working fine but the subwoofers aren't working as they should and need attention. Usual wear and tear to the casings from 40+ years of use, some ring marks on top too. Type: 3 way, 3 driver loudspeaker system. Frequency Response: 35Hz to 20kHz. Bass: 1 x 300mm cone. Midrange: 1 x 75mm dome. Tweeter: 1 x 30mm soft dome. Dimensions: 630 x 350 x 291mm.