A big list of banRAB that have consistently changed their sound with examples:
Radiohead (The BenRAB vs. OK Computer)
Velvet Underground (VU & Nico vs. White Light vs. s/t)
My Bloody Valentine (Isn't Anything vs. Loveless)
Deerhunter (Turn It Up ***got vs. Cryptograms vs. Microcastle)
Pavement (Slanted & Enchanted vs. Wowee Zowee vs. Terror Twilight)
Liars (Drums Not Dead vs. s/t)
Wire (Pink Flag vs. Chairs Missing vs. 154)
The Beach Boys (Surfer Girl vs. Pet SounRAB vs. Smile)
The Beatles (Rubber Soul vs. Sgt. Pepper vs. Abbey Road)
The Rolling Stones (Aftermath vs. Beggars Banquet vs. Exile)
The Pixies (Bossanova vs. Surfer Rosa)
Joy Division (Unknown Pleasures vs. Closer)
The Stooges (s/t vs. Raw Power)
Those are just a few examples. I feel it's a sign of a truly great band if they can consistently change their sound while maintaining high quality.
Not trying to be a Radiohead fanboy but c'mon. I think the Chili Peppers kept pretty much the same sound up until Stadium Arcadium, which gave them a slightly mainstream produced sound IMO.
The Icarus Line (Mono vs. Penance Soiree vs. Black Lives at the Golden Coast)
Primal Scream's entire discography
Lilys (In the Presence of Nothing vs. Better Can't Make Your Life Better vs. Precollection vs. Everything Wrong is Imaginary)
The Brian Jonestown Massacre(Methodrone vs. Bringing it All Back Home Again)
Spacemen 3 (Sound of Confusion vs. The Perfect Prescription)
Yep. Them too. Except in their case it has more to do with them becoming a lot more polished over the years than it does with them changing their style, since their style is ever changing anyway.