OK, be brutal, what do you think? PART 1
This is one of my 9844-8Bs pictured with a Genelec 1031 (boo,) and a Westlake BBSM-8 (yay!) behind. Please no comments on the ill-placed Sonex foam you will see scattered about, it is not my doing as this is not my control room or studio. I don’t own the other speakers either. In fact I did own Genelecs and happily sold them last Summer. If I can get the Altecs running satisfactorily, I will try some mixing with them in this place to hear how the result translates.
http://i183.photobucket.com/albums/x...B/IMG_1755.jpg
Inside one cab showing new GPA covers over the 902 drivers:
http://i183.photobucket.com/albums/x...B/IMG_1731.jpg
Inside the other cab shows one 414 appearing different, though it is stamped 414-16. Does this seem correct?
http://i183.photobucket.com/albums/x...B/IMG_1732.jpg
Close up of renegade woofer:
http://i183.photobucket.com/albums/x...B/IMG_1733.jpg
Compared to its room mate:
http://i183.photobucket.com/albums/x...B/IMG_1734.jpg
As you can see the previous owner had port tubes which I pulled off. Once I get things sorted out, I might want to try that to help the low end.
I measured and aligned the rear of the voice coils for the 902s and the Eminence APT200s. The tweeter’s setback position will cause bad reflections off of the cab:
http://i183.photobucket.com/albums/x...B/IMG_1739.jpg
So I went ugly and put on a sound blanket:
http://i183.photobucket.com/albums/x...B/IMG_1742.jpg
I made the next several unscientific measurements using my new DEQ2496/companion mic, from a 3 foot distance with the mic height exactly between both horns. Kind of aimed at the blanket. The room is a studio which has non parallel walls, though the ceiling and floor are. I used a Sonex gobo to help kill reflections from the close wall:
http://i183.photobucket.com/albums/x...B/IMG_1741.jpg
Continues in next post....
OK, be brutal, what do you think? PART 2
Continued from previous post.....
This is the result with both L-pads turned to minimum output:
http://i183.photobucket.com/albums/x...B/IMG_1744.jpg
The 902 brought in:
http://i183.photobucket.com/albums/x...B/IMG_1745.jpg
And the APT 200 brought in:
http://i183.photobucket.com/albums/x...B/IMG_1746.jpg
Since I don’t really know what the hell I am doing, I tried to get levels across the spectrum as even as possible, but I was looking from the other side of the room and should have done better. Here are the L-Pad settings:
http://i183.photobucket.com/albums/x...B/IMG_1747.jpg
Left pot is 902.
I then rolled the whole mess into a typical rectangular room with the idea of giving a listen. I also took some readings there as well. The room (a classroom) has hf absorptive panels on the left wall -- which you can’t see -- so I brought in the Sonex gobo for the right side against the blackboard:
http://i183.photobucket.com/albums/x...B/IMG_1764.jpg
For the next two readings, I can’t remember what the mic placement was...
I think it was about the distance between the speakers; first with 902s in “normal” phase, which is reverse polarity:
http://i183.photobucket.com/albums/x...B/IMG_1756.jpg
And now with 902 leads reversed so that they are actually in phase now:
http://i183.photobucket.com/albums/x...B/IMG_1757.jpg
Now for some potentially bad news. I decided to do a close check in this room for each speaker, which I did not do in the studio room (don’t know why.) So I went back to the 3 ft placement as shown previously, but stayed in the classroom. Left speaker:
http://i183.photobucket.com/albums/x...B/IMG_1761.jpg
Right Speaker:
http://i183.photobucket.com/albums/x...B/IMG_1758.jpg
Looks like the left 902 is 5 dB down at about 2.5k. And generally the curves are not as similar in that range as I would expect. But I have not done this before, so I don’t know how significant that actually is, given room placement differences. I did not roll each speaker into a single location. I simply measured them positioned as they were in the classroom image. Here’s the approximate L-Pad settings:
http://i183.photobucket.com/albums/x...B/IMG_1762.jpg
Right now I’d like to hear your opinions. After digesting what you guys say, I will see what I can do to make the 3way as good as I am able. I may also try the cascade filter modification suggested by Art J. Then I will definitely compare one three way to one 2way. And for this I don’t know if I should modify one of my existing crossovers or do you think I should build a copy of the original network?
I now see an attractive benefit of going active --- being able to change things on the fly.
Thanks for all the help!