Yes you can. There is a discussion of this on a very recent post on the Boulder Cable Circle under www.audiocircle.com

Hey, i am doing the exact same thing. exept i cant afford a good amp so i am just gonna push it through my cheap sony 2x100watt (pre-amp?). Anyhow, i dont have it set up yet but tell me how it goes. Btw, how does the squeezebox sound compared to cd? I read the review on the site but it always helps to have more then one opinion.

The volume control of the SB operates in the digital domain, If you run direct to your amp you will lose info and have degradation of the signal if the vol. is below a certain seting(below 60 ?).
There have also been reports of the "white noise of death" which can blow your speakers(although this is rare.)
Slim Devices CEO Sean Adams does NOT recommend SB direct to amp.
All this can be solved with an inexpensive attenuater that is "audophile" grade.

Go to the SD (slimdevices) website and check out the forums there.
You can find a wealth of info there on the SB and Transporter(I have both)
There are great folks over there willing to help with advice.
BTW, you will get a huge improvement in sound just by pluging the SB wallwart into a power conditioner. An even bigger improvement with the Bolder Cables modded Elpac linear power supply. This cheap upgrade gets you much closer to the Transporter.
The Transporter rivals the Ayre in my system of Watt/Puppies with Jeff Rowland electronics.

Have fun with the SB.