I'm going to be using the Delta 12LFA with the Denovo 360 on a SEOS12 for my design. I originally chose this design due to having found a deal on the Delta 12LFAs used. However once I began looking several of their features I found desirable. First they are happy in a much smaller sealed box than the Delta 12A. The response curve is pretty flat with an internal volume of 2.0ft^3 while keeping excursion under x-max down to 80Hz without a high pass with 125W. I like the concept of sealed mains since my subs are sealed and I never really liked mixing the two... Ive contacted someone to help me with the crossover, but this will take some time as I'm not in as much of a hot hurry and have some other projects in front of this.
Update: Got my shipping confirmation from Erich Today. Eminence Delta 12LFAs will be here this week and I had one shipped one to a charitable soul who is going to check out Bwaslo's crossover on it with the SEOS and 360...... OK, I would like to ask for advice on the enclosure for the Eminence Delta 12LFA. It is already programmed into Winisd so not that hard to model up. As previously mentioned I am leaning toward sealed but I'm concerned that the roll off is too steep. Its -5db @80Hz sealed in 2.0ft cubed. I can get the design flat to 80 with 60Hz tuning and F3 of 80 with 50Hz tuning in 2.0 ft cubed. Subs Sealed. Questions: 1. Is the -5db @ 80Hz too much of a roll off? 2. Assuming 80Hz crossover from mains how far does the tuning frequency of the mains need to be away to avoid cancellation from port interaction? 3. Which alignment would you choose? Sealed, 50Hz, or 60Hz tuning?
With subwoofers available, sealed. Don't forget that a port is only "in phase" at specifig frequencies and out of phase at others. That makes subwoofer integration tougher. A couple of hertz is no big deal at those xover frequencies. It is only a difference between a low E and low F: http://www.phy.mtu.edu/~suits/notefreqs.html
Thanks thats kinda what I was thinking. Its easy to become obsessed with a db or two. If the response dips at all a small boost in EQ with the subs will smooth it out anyways since theyre both sealed they should be playing nice. I plan on stuffing the box even though its Q is already .710 so it might help out the low end by a db who knows....... that makes the box easier too.
Thanks I still think it will work at 80Hz on paper maybe a little lower or higher in-room, just depending on how it measures...... Nice avatar, MJ is on of my all time fave BB players.
Woot! The drivers came in yesterday and the waveguides and CDs today.... Guess i can get started with the cabs in my spare time. Prob build a test box first to see how the LFA behaves in 2.0ft cubed.....
Bill was kind enough to test the Delta 12LFA with his crossover and also did some extra tweaking to get it to work. Crossover: Now I just have to finish up my ventilation project in the HT so i can start building these! P.S. I go by NicksHitachi on AVS. ;D THANKS BILL!