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Replacement woofers for Altec A-7?

There are some pics and a brief description of the A-7/Lab horn sub set-up I heard at the second Midwest Audiofest here (under the Chicago Horn Club heading).

I remember that system. I almost bought those Edgar Trimlines, but by the time I had made a phone call and grabbed the checkbook, they were gone.
 
Drivers came in! WOW I am impressed. I lowered my port to 3.5" and like it right there, now I am going to experiment with the crossover.

I have the 511B/902-8B. Im going to try switching to 800hz. Probably pick up some 902-8A's down the road since I already noticed a strange type of "shrill" in the female voice in one song I was listening to. Not sure if its my Lpad setting too high, xover, or the 902-8B....problem too is that I cannot remember the song so I have to wait to hear it again

Bowtie will tell you that the 902 CD won't match properly with the 811/511 horn since they are actually slightly smaller sized, 7/8" versus 1" IIRC. You may want to look at 800 series drivers instead...

Agree here with Bowtie and Bill, if you want low bass you ain't a'gonna get it with a 825-828 box.

I dig 416 woofers and not because of their ability to do low bass but the gorgeous way in which they reproduce upper bass and midrange, IMO there's only one better driver in that range, the 515. Which by the way makes even less bass than a 416 when in a 825-828. The 414 12" is swell too.

Anyway if you want deep bass with 825-828s you gotta use a sub and it better be a big one that can track the dynamics of the VOT. When I had A5s I used a pair of JBL 4648s below 100hz. That gave me 4-15s. They were placed along a wall and EQed +6db at 30 hz. They kept up with the dynamics of the A5s and were flat to 25hz, measured.

Tom is right. I use a pair of JBL 4685's each with 2 JBL 2225h 15" Drivers powered with a pair of Ashly FTX-2000 pro amps, good for 800 watts each in bridged mono operation. You really need something with some real kick to keep up with big Altecs....



 
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I found a quote from Bowtie: "You'll find the number of applications where Altec used it below 1.2khz very limited.

902's were optimally designed for the Mantaray series of horns which had 7/8 inch throats to mate the 7/8 inch aperture of the 902.

511's have a 1 inch throat, and the 800 series drivers designed for it have a matching 1 inch aperture.

You can run 902's on 511's. But it's a less than optimum match as it puts a step in the throat and doesn't maintain a constant throat angle, the higher the XO the better. Altec ran 902's on 511 only for pro(read high power) applications and above 1.2khz."





Seems like I am working backwards due to my very limited knowledge with Altec. I know i'm not satisfied with the 902B/511B setup so I need to get this resolved.

As far as subs go, I am covered. I use two custom cabinets. Each cabinet houses 4-18" Stereo Integrity subs. 4 Behringer EP4000 amps supply power. They are blending well with the 515LF's.

I need to get my horn dilemma figured out.
 
Thanks guys,

Analog Addict- I like those horns!! Nice setup btw :)
I bought the 828's for three reason primarily, better midrange, snap, match my 125wpc tube monoblocks. The least of my concerns was bass although they are better now that I decreased the port size.

What model are your Altec's? Very nice!! EDIT: A4's now those would be nice next to my behemoth subs!
 
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Now that you mention it....

Thanks guys,

Analog Addict- I like those horns!! Nice setup btw :)
I bought the 828's for three reason primarily, better midrange, snap, match my 125wpc tube monoblocks. The least of my concerns was bass although they are better now that I decreased the port size.

What model are your Altec's? Very nice!! EDIT: A4's now those would be nice next to my behemoth subs!


Well not exactly. That's my center channel, a 210 cab with two 515s and a 288B on a TF 1005. The A4 is a 210 cabinet with the wing on either side, giving it extended bass response. I may try to put together a set of A4's before the end of the summer....

Anyway, here's the right side stack...The 828 cabs you see there have a set of 604-8Gs that I run at the same time as the big stacks via a speaker selector box. The 816VI/MR94 combo is not currently hooked up.



And the left....



As folks here can tell you, I never miss the opportunity to blow my own horn(s)....:D

I had my old buddy HomerJSimpson over Monday night, and I can't tell you how long it's been since I've had someone over who actually sat and really listened to the music.
 
Seems like I am working backwards due to my very limited knowledge with Altec. I know i'm not satisfied with the 902B/511B setup so I need to get this resolved.

As far as subs go, I am covered. I use two custom cabinets. Each cabinet houses 4-18" Stereo Integrity subs. 4 Behringer EP4000 amps supply power. They are blending well with the 515LF's.

I need to get my horn dilemma figured out.

If you want a 1" version of the Altec compression driver with ceramic magnets, but don't care if it says "Altec," seek out some Emilar or Renkus-Heinz drivers from the 1970s and 1980s. The elder Renkus designed both after he left Altec. I have a pair of R-H SSD1801-16 drivers bolted to 511B horns, and they sound fabulous.
 
The only problem with the Emilar and R-H drivers is the rather flaky diaphragm availability. Orange County Speaker still has 16 ohm SSD1801 diaphragms, but they want a stupid amount per unit. Fortunately they're pretty indestructible if you don't do anything stupid to them. There are also full mylar replacements available for R-H.
 
Damn those some nice horns!! very nice stuff!!!

Well not exactly. That's my center channel, a 210 cab with two 515s and a 288B on a TF 1005. The A4 is a 210 cabinet with the wing on either side, giving it extended bass response. I may try to put together a set of A4's before the end of the summer....

Anyway, here's the right side stack...The 828 cabs you see there have a set of 604-8Gs that I run at the same time as the big stacks via a speaker selector box. The 816VI/MR94 combo is not currently hooked up.



And the left....



As folks here can tell you, I never miss the opportunity to blow my own horn(s)....:D

I had my old buddy HomerJSimpson over Monday night, and I can't tell you how long it's been since I've had someone over who actually sat and really listened to the music.



I started a new thread for questions about my horns and posted some pics of my subs:

http://www.audiokarma.org/forums/showthread.php?p=8879332&posted=1#post8879332
 
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