I use both the 2012 & the 2123 in small SR cabinets ( delay +/or front-fill boxes that don't handle much below 100hz ).
- In that capacity, I find the two models interchangeable ( & audibly, mostly indistinguishable, once EQed ) .
Ultimately though, (at the end-of-the-day PLUS all those other tired cliches ) the 1/2" deep gap ( of the 2012 ) should offer the listener, a higher resolution listening experience .
The trouble is, there are countless different ways to derail arriving at that audible benefit .
- For instance; nothing turns great audio quality ( quicker ) into some piss poor sounding ( MP3-like ) listening experience, than lousy acoustics ( which is normal in my work experience ).
Anyways, Good Luck NWCg with your project !