Try getting him some really good modern stuff to listen to. This is one of the best albums I've ever heard. If he likes more musical stuff this album has really great sounds. It's not like any of their old material. Though some of the songs are a bit pop like (Across The Night, Luv Your Life)
Click on the picture for audio on their site (it's a flash site)
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I recomend checkin out My Favourite Thing (beautiful song), Tuna In The Brine (don't know how to describe it..epic I guess), After All These Years (piano song). Customer reviews of this album are probably 95 to 98% positive even for some who have been fans of the band since their VERY different sounding Frogstomp days.
For instrumental musicianship. Godspeed You Black Emperor will more than likely blow him away. They usually release 2 or 3 songs an album, each song being about 30 min. long and just really intense to listen to. Guitars, horns, celo's, strings, etc.
Pearl Jam rock my world if he doesn't have Ten yet he needs to get it. If he doesn't want to listen to anything modern and lean more towards classic rock than Yes (I recomend Close To The Edge or Fragile) and Rush (2112 or Moving Pictures) are pretty fuckin perfect to me. Queen (ANYTHING!) also. For all instrumental Tangerine Dream got a lot of praise. Traffic made some great music. Alan Parsons Project, Electric Light Orchestra, etc. etc. Theres lots of stuff out there that fit that criteria I'm sure you'll find something.
Asta!!