1 iMac, 2 iTunes Match

[canuckle]

We have an iMac, 2 iPhones, 2 iPad's. We have separate iTunes accounts. But, the iMac can only be used with one iTunes Match account?

Say it ain't so, I have something wrong, yes?

[HazyCloud]

I don't see why it couldn't, but you'd have to sign in and out of the iTunes Store to get access to each account.

Also, are you trying this under the same login or separate?

[bucksaddle]

iTunes match invokes the 90 day Apple id rule, so in answer to the question you cannot use 2 iTunes match accounts on one computer unless you are willing to wait the 90 days.
Note that the 90 day rule applies to the computer as a whole, not OS X user accounts - so even if you create another user account on your iMac for the 2nd iTunes library you still cannot activate iTunes match on that account.
I use a VM to manage my 2 seperate iTunes match accounts.

[canuckle]

HazyCloud, it is 2 user accounts.

This makes no sense to me.