I recently had the good fortune to pick up a slightly used Newform R630 kit (2 30" ribbon, 2 18W/8545 woofers) that hasn't been put together yet. A friend and I are going to build a 4-6 woofer array using one or two NFR ribbons per channel. Plan right now is to have the overall height to 60" and incorporate 4 woofers, spaced 180mm ctc. The ribbons will be positioned to the side similar to Brad Virgils original R45 ribbons in the Excelarray. I've ordered 6 more 18W-8545 drivers (total 8) from Solen for this project. I may add 4 more woofers if necessary but would like to take a modular approach before adding the extra 2 per channel, is this feasible or would it be better to build the project from the start using 6 mids/channel. With 4 8545 and 1 R30 per side nominal impedance will be 8Ohms but there will be an efficiency mismatch from my calculations. 6 mids and a pair of R30's per channel give a lower nominal load and a 94dB sensitivity match if my calculations are right.
I've been diligently reading Jim Griffin's white paper the last couple days and any help would be appreciated.