Are High Speed CD-RW discs (4x-12x) readable in older CD-RW drives?

[jrichrds]

Is a High Speed CD-RW disc (4x-12x) readable in an older CD-RW drive that only writes 1x-4x CD-RW discs? I know as far as writing is concerned, High Speed CD-RW discs aren't backwards compatible with older CD-RW drives...just not sure if that applies to reading as well.