Lest you think all I do is lurk in the shadows and ask an occasional dumb question, here's what I've been up to:
I stumbled across this thread back in January or February when I was looking for some information about alternative drivers and cabinets for my Altec 811B horns. Well, I was completely mesmerized by the whole collaborative design exercise, so I started trolling eBay and the Lansing Heritage marketplace for a pair of cabinets to e-wave, in addition to the pair I needed for the 811B’s.
Early on, I decided that cabinets with removable front baffles would be easier for me to modify, so I concentrated my search on early 1970’s era Altec model numbers. The short integral pedestal of certain models seemed to have saved them from the wet basement or carpet storage splitting and swelling of other floor-standers, and or course, the Santana pseudo-slate plastic tops eliminated the death-by-houseplant syndrome. In the end, I wanted to wind up with something I could put in the living room, an otherwise formal space with no audio gear.
To make a long story short, after a false start with a pair of Yamaha cabinets that were just too cheaply made to fool with, next thing I knew, I was in Columbus, Ohio at Ron Speakerman57’s house, picking up a pair of Altec Santana II’s, a pair of Altec 879A Santana’s, a pair of Altec 891A’s and a pair of JBL 123A-1 woofers. A couple of weeks later a pair of Altec 872B Madrid’s, which amazingly had never been used as a plant stand or wet bar, fell into my lap.
To top it off, this affair is my FIRST speaker project ever. Never built a crossover or made a front baffle before, never took a Sawzall or sabersaw to a speaker cabinet. No real experience with a router. Since then, I’ve become pretty darn handy with the router, which has become an invaluable tool for fabricating front baffles.
I also either already owned or accumulated a pair of JBL LE120H-1 woofers, two pair of LE14A woofers plus the pair of 123A-1 woofers. The Altec Madrid’s came to me with a usable pair of Altec 420A 15” bi-flex woofers.
So my current layouts are thus:
Santana II: I’ve cut the front baffles out of the Santana II’s and made new front baffles that accommodate the 811B’s and the pair of JBL LE120H-1’s. LE14A’s will physically fit, but would require fabrication of a new baffle, which is now almost a trivial undertaking. These need the most cosmetic help, if only because they have the most edge-banding to replace.
Altec 891A: I originally bought a pair of the 8”x8” JBL PT 365124 waveguides for the Altec 891A’s, but the original offset tweeter meant that the new waveguide would have to be offset too, so I shelved them and cut the front baffles for the standard 338800 WG. The JBL 123A-1 woofers drop into the original Altec woofer recess, but require new mounting screws. Cabinets are sanded, rubbed down with 0000 steel wool , oiled and look good. Cosmetically, these are essentially done.
Altec 872A Madrid: The 338800 WG would not fit between the 420S woofer and the top of the baffle, so I made new baffles relocating it down about 1”. Since the 420A mounts from the rear of the baffle and the WG from the front, they can now overlap and just fit. Cabinets are sanded, rubbed down with 0000 steel wool , oiled, looks good. Cosmetically, these are essentially done.
Altec Santana 879A: Cut new front baffles for the 338800 WG and a JBL LE14A. Still need quite a bit of work in the cosmetic arena. The front beveled edges were pretty beat up, so I bought a piece of black walnut board and had a friend cut new solid walnut replacements for the old veneer-wrapped MDF originals. Still have to cut the old off and install the new and replace the edge banding around the top.
So, it looks to me as if I will need to build three different versions of the E-wave crossovers:
standard for the 891/123A-1 setup.
high-efficiency for the 97 dB 420A/872A.
900hz low pass for the LE14A/879A Santana.
I’m using the available E-wave crossover PCB’s.
How critical are the crossover resistor values? When I was trying to order parts for the non-standard C/O’s, I found that PE didn’t always offer the 10 watt resistors in exactly the spec value. Is 25 ohm close enough to 24 ohm, or 15 close enough to 16 to suffice? Does anyone find fault with my driver combinations given what I already own?
ara: 
