Originally Posted by
RMC
Hi mortron,
Somewhat late to the party, but this might help you.
The Enclosure Guide's 1.5 CF, Fb 80hz, is good for E120 as woofer in a two-way system for example (read the note at bottom of page 1 of Enclosure Guide, the E120 is not mentioned there, indirectly confirming my statement).
As i understand it (since i'm late), your driver application would be to use E120 for low-mid. Checking the TS for the driver, Qts is very low at 0.17 which helps in reducing box size to house the driver.
In such application driver is usually housed in a small closed sub-chamber. But the best way to know for sure which size box is to model the driver in speaker design software.
According to Eargle's Loudspeaker Handbook the upper limit for a 12" is 875hz @ DI 6 db, and somewhat stretched is 1313 hz @ DI 10 db. So more directional (this being a musical instrument driver it most probably has a rising response that you may benefit from, with the inconvenience of having more directivity).You decide if proper
Driver EBP is 315 in principle driver more suitable for horn, but not necessarily a no here. Regarding the Graphs:
First assuming 2 Pi box placement, then second one with baffle diffraction loss (no 2Pi), somewhat better for low-mid (you're actual result may be somewhere in between)
Standard QL 7, this can be increased to QL 10 due to small box size, if well made, higher QL means little smaller box can be used because of reduced losses, but at some point need to have enough volume to fit the driver in.
1 or 1.5 cf response graphs i get from modeling are practically the same.
At first sight, 1 cf sub-box seems feasible as per dimensions given to me by Winspeakerz software, with a little "cheating"/adjustments (H vs W vs D).
I'll post my graphs and sub-box dimensions later tonight, gotta go now...
Richard