"soft power" control of IDE drives?

Is it possible to configure (with jumpers?) an IDE drive in such a way
that it *doesn't* automatically spin up when power is applied to it, but
it rather goes into "standby" mode and waits for a software command from
the computer to fully turn it on?

The reason I ask is because I'm considering getting a dual drive
enclosure (the OWC RAID enclosure:
http://eshop.macsales.com/item/Other%20World%20Computing/MEFW912AL2/),
but set it up for two independant hard drives where one of the drives is
used normally, for video/audio, while the other one is used only now and
then for backing up the first drive.

To save tear and wear on the backup drive (and any additional noise) it
would be great if it could just turn it on when I need to do a backup,
and otherwise have it turned off.

A dual-drive enclosure would save me the clutter of yet another AC power
adapter, another Firewire cable and yet another "box" on my desktop.