That's a tried and true design by renowned speaker designer D. B. Keele Jr. Works very well.
I wonder about making a side by side 2x15 version. Probably too heavy. Did you use an Electrovoice speaker? How much does it weigh?
The TL606 is probably the most knocked off bass cab in history, and for good reason.
A tried and true excellent all around full range bass guitar cab, I wouldn't
personally muck it up with a compression driver but to each his own...
Reeves has the Trace Elliot version of the TL606 that we used for comparision when testing designs for the Reeves 115 cab.
This is
half of the speaker compliment of EV TL606's my buddy Chris uses for his live rig, with one of
his EVM loaded 215S cabs on top. That's the Reeves 400 watt prototype sitting on it, but he drives his personal rig with SVT's; and runs them wide open.
Instant, permanent hearing damage without ear protection but kinda fun if you are prepared!