I've built a 30W amp that is basically a Z-Wreck-like front end driving a pair of El-34's (not a quad of EL84s), and I'm looking to find the perfect speaker matchup for it. It is a head and cab config, the cab is a Swanson closed back 2 x 12". Right now I have it loaded with 2 x Celestion G12H-75 Creambacks, and I am not liking the result. The high end of the G12H's I have in there is too strident. I'm thinking either in terms of the G12M-65 Creamback, or maybe G12M Greenbacks. Celestion confuses me with their model designators -- what is the difference between a Greenback and the Heritage Greenback? How do Golds perform in a closed back cab?