Speaker cabinets for 416B's and 811 horns

[Gerald DiMauro]

Hello Everyone,
This is my first time in this forum and I love it since it's *****d with Altec lovers like myself. I was introduced to Altecs in 1970 when my father bought our new Heathkit family stereo system with 416B's and 811 horns. I was absolutely blown away then and I still am to this day. Recently I picked up the same components but I need cabinets for them. My floor space is limited so I'm leaning toward something like the Valencia or there about in size. Can anyone tell me if there is a difference in sound quality with regard to highs and lows if I use a speaker cabinet of this size for my Altecs? Most important is the fact that I am looking to buy a set of cabinets now. Please point me in the right direction.

[Charles Chance]

I'll leave the tech. info on cabinets to those more knowledgeable than I. I would only warn you that the word f_i_l_l_e_d is a bad word on this forum. I got caught using it and I'm very ashamed of myself.

[Gerald DiMauro]

Hi, Charles
What on earth is the problem with f-i-l-l-e-d ?

[Fitts]

Hi,

No comment on the F word.

The cabinet is primarily going to affect the low end. The horn is the high frequency "enclosure" and needs little consideration except that you should try to design your cabinet so as to align the horn and woofer sound producing surfaces in the same plane. This can be quite a trick and not always possible if you are going for a really small box.

Using the T/S parameters I have for the 416-8B it seems the very best cabinet would be one that has an internial volume of 7.6 cubic feet into which you cut a vent or vents having a total area of 130 square inches. When doing the caculations, be sure to remember that the speaker is taking up some of the internal volume and has to be allowed for, the same applies if you mount the horn inside the cabinet.

All this means that for two 416 woofers you will need about 15 cubic feet of cabinet to get the best sound out of the 416's. Maybe you could design a cabinet that doubles as a entertainment center or maybe some one else has a smaller cabinet design they could offer if you need smaller.

Happy listening,

[David Deratany]

What am I missing?

604b in 7.5 foot box. Granted the lf transducer is not a 416, but it isn't that far away.

An Altec engineer said that a ~20 sq. in. vent would give me an F3 just under 40 hz and that it would be satisfactory. Others have said 12-16, since it has a D/E cone, would take the corner a tad lower.

[Gerald DiMauro]

Dave

Thanks so much for the cabinet specs. Seems like I'll have to have them built afterall. Thanks again.

[Fitts]

Looks like the vent size is questionable. Perhaps making the cabinet with a small vent to begin with and experimentation to get the best performace would be in order.

Best wishes,

[David Deratany]

Could that 130 be sq. cm.? That would get us to 20 sq. in.

David Deratany

[Steve Burger]

We at Iconic Manufacturing have several options for you. Our cabinet maker David Florio does excellent work. You can find a post earlier from Jeff Marquart who recently had us build a set of custom enclosures for his 604b Duplex speakers. We have several different designs as well as the ability to reproduce a number of cabinets from several of the famous "West Coast" speaker companies. We are also hypersenstive to the needs of many to have speakers/furniture we build maintain a high level of SAF (spousal approval factor). If you email me I can send you some pics of some of our finished products.