View Full Version : Altec 515b Woofer Cabinet Suggestions

02-09-2010, 11:07 AM
Hello Lads,
Can some of you make suggestions for cabinets for the Altec 515B woofer? I have a pair of A5's with Jabo conical horns, and Behringer crossovers running right now, they sound great, but I do need a better Xover.

The point is, the tremendous size of the A5 boxes is eating into the room space.
If they were even a foot less in length and width, it would be a bit more manageable in my front room.

Are there any of the Altec or JBL bass reflex box designs for the 15" woofer that would help deliver an equivalent sound with a smaller footprint?

Thank you,
Donald Bowm

Earl K
02-09-2010, 11:43 AM
Hi Donald,

Bona Fide A5s are quite rare ( as well as being very large ) .

Here's a rendering from an old catalogue . Is this what you have ?

Even without the wings ( bass extenders ) the basic box is larger than an A7 .

http://www.voiceofthetheatre.com/images/vottcatt1945.10.jpg (http://www.voiceofthetheatre.com/)
http://www.michaelchrist.com/gifs/downstairs.jpg (http://www.michaelchrist.com/vintage2.html)

- There's a good thread here (http://www.hostboard.com/forums/altec-users-board/149644-duplex-within-bass-horn-a6-1945-a.html) that talks about the A5 .
- Dimensions are given ( for the cabinet portion ) if you want to verify that you have A5s .
- Note that one member in the thread was looking for a single .

- If you can't live with the size of A5s the logical step downwards ( in size ) is to the A7-500 .
- Here's a favourite thread of mine (http://www.hostboard.com/forums/altec-users-board/190741-my-a7-500s-journey.html) over at Todds' Altec Hostboard. It's about getting optimizing a pair of A7-500s for the best in room response .

>< cheers :)

02-09-2010, 12:15 PM
Thanks for the reply's. These cabinets are loaded with 515B Lows, and came with 288C HF drivers with 311-60 horns.

I have been told they are A-5's by some on this board in another photo, but here is a photo of them in my living room.
They cam out of a college that had made the original purchase in 1969

Thank you,
Donald Bowman

Earl K
02-09-2010, 01:31 PM
Sounds like you have A5's not A7's. The cabinet is the same.

I have been told they are A-5's by some on this board in another photo, but here is a photo of them in my living room.

- Yes , I now see the source of your confusion ( funny that ) // whatever // the fact is, you aren't happy with the size of these cabinets and want smaller boxes .

- You should also post this question over at Altec Hostboard (http://www.hostboard.com/forums/altec-users-board/). ( Since I don't have any 515b speakers or VOTTs , my ability to help is pretty limited . )

- GM might reply and may tell you to build BR boxes ( or MLTL ) equivalent to the size of the 515b(s) VAS / tuned to the woofers' Fs ( IIRC ) .
- Apart from the compromise this forces upon "Xmax at full full power" // this appears to be his standing advice / which has never resulted in any blowback ( that I'm aware of ).
- Also, driving them with a period amplifier ( tube amp with lowish damping factor ) is another bit of standing advice .

<> cheers

02-18-2010, 03:21 PM
Just wandering what Duplex model is seen on that picture of the A6.