Edit: changed final build to a 10cu ft Coffin tuned 19Hz, too late to rename the thread title! Doh
Well, it's that time of year again to build another sub. I decided to replace my current 15" nearfield drivers with a single and lower tuned 21" pro audio driver that seems to be all the rage these days. For father's day, I ordered the LaVoce SAN214.50 21" and a gallon of duratex for less than $500 using the $50 off coupon: https://www.parts-express.com/lavoce...8-ohm--293-732
finished his testing recently of this driver, and he said "at the current street price it represents an outstanding value." To me, it appears to be almost identical to the 21" B&C 21DS115 for $140-225 less (currently on sale for only $375 on PE!). Unfortunately, the only SAN214.50 available for sale is 8ohm (LaVoce website states they're built in 4ohm or 8ohm but not finding any yet), but that's OK, because I won't need 1700watts pounding me in the back anyway. I'll be powering it with an iNuke 6K, so should get a good 800-1,000w into an 8ohm load. I modeled it with 1,000w at 18" distance from the driver if you're curious why the SPL graph is so high, but will likely never run it anywhere near that loud.
I played with winISD a while to get these measurements and box sizes down to something more manageable to replace the two slim boxes behind my couch that
helped design only a year ago (they still rock John!). Everything seems to be a solid fit for excursion, port velocity, amp load, signal shaping and and final tuning for the box size. There’s probably a little more that could be done, but I’m pretty happy with the results.
Also, without flush mounting on the double baffle, the driver will only have 1.5" of clearance from the port back wall in such a slim box. For the final dimensions, I also took a little more than half the port width, which was 11”, off the port length from the WinISD estimation to account for the back wall. Hopefully everything checks out.
Edit: changed final build to a 10cu ft box.
I'm excited to start this build in the coming weeks! The driver arrives Wednesday. Cab will be 72”x24”x16” to replace these:
for these mock-ups!
Any questions or concerns regarding my build?
That’s a big thirsty driver!
Cab coming along:
Red is the LaVoce SAN214.50 21" tuned to 19Hz in 10 cu ft with EQ, yellow is 20Hz tune same cab different EQ, and green is the current nearfield RSS390HO-4 15" tuned 22Hz in 3.2 cu ft cabs. Depending on which EQ configuration I go with post calibration shown in the two SPL graphs, The Coffin will have a ton more output at both ends of the spectrum than my current 15” driver; I have two 15” drivers behind the couch now though spread out, so even subtracting 3-4dB for the second sub, it’s still a pretty killer upgrade across the bandwidth at only 60% power to the 21” LaVoce.