Yes: The Yes Album - 1971
This was the album where Yes really started to develop the prog rock style that would go on to serve them so well - extended tracks and all manner of musical diversity.
Yours Is No Disgrace is a wonderfully heavy bass, drum and crazy organ-backed proggy freakout. It sort of exemplifies prog rock for me - all those organ swirls and changes of tempo, with occasional vocals between long periods of instrumental virtuosity. As with all Yes's stuff, it is not my favourite sort of thing, for sure, but it has a heathy thumping sound to it and I find myself getting into it quite easily in places. There are numerous examples of great instrumentation in it, too many to list, to be honest. It is the best track on the album in my opinion.
The Clap is a somewhat incongruous seemingly live bit of throwaway acoustic guitar folky fun. Starship Trooper returns us to what was quickly becoming the norm for Yes - a lengthy, changeable number featuring organ, acoustic guitar etc. They were setting musical trends on tracks like this for the next few albums and for the prog rock genre in general. As with all the tracks like this, I really like bits of them, but listening to the whole can be a bit of an exercise in patience. I love the heavy rock-style guitar work near the end, though.
The opening acoustic bit on I've Seen All Good People sounds just like America's Ventura Highway although the track goes on to be typically Yes-operatic, vocally, until, about 3:45 we get some solid rocking, Beatles-ish parts.
A Venture is a Supertramp-sounding shorter, breezy number with some jazzy Mike Garson-esque piano in it too near the end. The album ends with another archetypal Yes number in Perpetual Change. The single versions of I've Seen All Good People, (titled Your Move) and Starship Trooper are, as seems to be the case with Yes, more defined and more effective.