Altec 815 question

[hatrack71]

So, I have a line on a pair of these double 15" flairs. I already have two pair of 8 ohm 416s, a pair of N501-8A crossovers and will have two pair of 299-16As on dual throats with 804Bs. I plan to bead blast the horns and have them repainted at a buddy's auto body shop before I do anything. My question is the impedance mismatch problem with the woofers at the crossover. If they were 16 ohm, I could just strap em together and be good. But they are not. I am wondering if I can just use one 416 and either block the other opening or make an adapter plate with a tuned port. Any suggestions?

[Altec Best]

The 804B's are they tar-filled or do they have Aquaplas on them ? If they are Aquaplas you don't want to remove the Aquaplas dampening coating on them.I also think single throats are all you will need in a home enviroment...

With large format drivers dual woofers are the best way to go IMHO. YMMV though. You will need to really pad down the HF to get them to play equally (HF & LF).

[bowtie427ss]

Bi-amp, and probably start looking for some kind of woofer solution to cover the bottom octave. 815 rolls off fairly steep below ~100hz.

If you run them wide open on the bottom(no hi pass filter) you really want to be careful about putting much power to them or you risk damage from over excursion.

Altec recommended a fairly steep(18db/octave) hi pass filter at a minimum of 70hz which is a bit lower than i ran them.

They have the most awesome mid-bass punch combined with the midrange you'd expect from Altec.

EDIT: You could also swap out the LF section inductor and cap in the N501 with 56uF and 1.8mH, to give you 500hz at 4 ohms. But, i think this will create a wider than ideal impedance swing for transformer coupled amps. Not as much an issue if you're using solid state to drive them.