THD 2x12 guitar cabinet for BASS?
 

I have this wonderful stock THD 2x12 cabinet that I use for Guitar.
Can I also use it with a BASS head?
I am primarily using it for home practice with an ASHDOWN 300 MAG head.

Keep the volume low or you will wreck the speakers.

I wouldn't even consider using that as a bass cab. Get a dedicated bass cab unless you plan on buying guitar speakers regularly.

+1 bass can kill a guitar cab with little effort. I wouldn't do it, even at low volume.