How to change header logo link

Is there a way to customize the header logo link to something other than the default homepage url?

I have a subdomain, like shop.mydomain.com, and would like the header to link back to my main site — mydomain.com. (I use the same Epik theme and logo/navigation for both.)

I found this code to “modify the header url” in Studiopress:

http://my.studiopress.com/snippets/header/

But that made the title of the site show in the header along with the logo. (So then the title was linked to the custom url, but not the logo.) I was not able to remove the text title and just have the logo with the new link.

So, I was wondering how I can just change the url for the logo.