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Altec 846B Foam Horn Surrounds - Pix Please?

Zonker92

Zonker92

All shiny and chrome
I have asked Paul Darst, the kind fellow who makes replica Altec Model 19 foam horn surrounds, to make some for my model 846Bs (AKA second generation Valencias). I have never seen any original foam surrounds for this speaker. Mine originally had fiberglass instead, but some people have suggested that it sometimes came with foam around the horns.

I have made a good template for Paul in terms of the vertical layout, but as for its depth, I can't tell if the original foam would have been flush with the front edge of the trim strip that supported the grille, or the back edge of that trim strip, or some other design.

If in fact there is such a thing, can someone who has the original 846B foam surrounds please post or send me some good photos or information? Thanks so much!

Eric
 
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I've never seen such a thing outside of the stock foam grilles that will have given up the ghost decades ago. Went back through the Altec catalogs at Lansing Heritage and I don't see a model from the brochures there, either.

Interesting idea, though.

Cheers,

David
 
Holy probable refutation of doubt, Dan! I wasn't sure they even existed either. You da man!

You wouldn't happen to have their measurements, would you? :) (Actually, with those photos I can pretty much measure them out myself, if they're exact fits to those openings.) But do they have any special cut-outs? And are they slightly oversized for those spaces or are they exactly the same size as each of those openings?

How confident are you that they're original? The reason I thought that some 846Bs came with foam, is because when I posted here a few weeks ago to announce that I had bought a pair, one of the first questions someone asked was whether mine were "the version with fiberglass around the horn, or the version with foam;" something like that. I can't find that post now.
 
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Those look to be cut from less than vintage foam. Their fresh/resiliant appearance contradicts their suggested vintage.

Post at the Altec user's board, i'm very doubtful those are original. But, the fellas that built them and sold them new will put it to rest. I know of no acoustic grade foam available in 1975 that would even remotely still resemble foam today at 35 years of age.

I believe, but cannot confirm that Altec's first use of foam to damp horn mouth area was on the model 19 to be more cosmetically appropriate for the model 19's finished baffles, as a damping material fiberglass is superior and much cheaper.

Just my .02........................
 
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Looks like the foam I used around my horns on my A7
 

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Indeed, it does. Dan's look like they were painted; you can see some lighter areas on the fat ends of the wedges, which are covered when installed.
 
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My pleasure! By the way, what do these surrounds damp anyway? Horn body resonance, sound waves reflecting off the baffle, or both?

As for horn body resonance, I removed the fiberglass because it's so damn ugly, but then my horns seemed a lot harsher on vocals. Last night I put some crescents of Damplifier Pro (similar to Dynomat but cheaper and, in my opinion, much better) on the outside surfaces of the horn mouth "lips", above and below, where you can't see it.

The stuff is awesome. It's black, very dense, and sticks and conforms perfectly, but you can peel it off again in an instant. Anyway, suddenly my horns sound good to me again. Maybe it's all in my head, but to me it seemed to make a huge improvement; that metallic sound is gone. When I remove the horns to put 902 drivers on them I'll use it to cover also the exterior horn surfaces behind the baffle.
 
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OK, I measured what appear to be the dimensions from those photos, off my own speakers:
  • Top rectangular section (Width x Height x Depth): 23 7/16" x 1" x 3 3/8".

  • Wedge side pieces: The side facing the rear of the cabinet is 3 5/8" wide x 6 15/16" high. The fat (outside) end of the wedge is 2 5/8" deep. That end of the wedge comes out at a 90-degree angle from the rear face. The face of the wedge tapers inward to its thin edge. That front face is about 4 7/16" across.

  • Bottom rectangular section (W x H x D): 23 7/16" x 7/8" x 3 3/8".
Does that correspond with your foam pieces, Dan? Thanks again!
 
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Also:

Mustang Marvin said:
Mine are 7315 and 7316. The foam is gray, but painted black where you see them. There was a foam grill which was removable. It disintegrated long ago. The foam around the horn is still good. I replaced the foam grill with black acoustical fabric. I had the compression drivers (806) rebuilt by GPA. I have always taken the best of care of them. They still sound great.
MM
Click to expand...
 
Zonker92 said:
OK, I measured what appear to be the dimensions from those photos, off my own speakers:
  • Top rectangular section (Width x Height x Depth): 23 7/16" x 1" x 3 3/8".

  • Wedge side pieces: The side facing the rear of the cabinet is 3 5/8" wide x 6 15/16" high. The fat (outside) end of the wedge is 2 5/8" deep. That end of the wedge comes out at a 90-degree angle from the rear face. The face of the wedge tapers inward to its thin edge. That front face is about 4 7/16" across.

  • Bottom rectangular section (W x H x D): 23 7/16" x 7/8" x 3 3/8".
Does that correspond with your foam pieces, Dan? Thanks again!
Click to expand...


Close. I measured the top and bottom sections as: 23 1/2 inches wide, 3 deep, 1 inch thick. Corners are 7 inches tall, 4 inches wide, 2 7/8 from the 90degree back edge each way. The areas that are visible are stained black.

I have had this set for about 4yrs. I purchased them from a gentleman who claimed to be the original owner. I have no way of knowing when or if he replaced these pieces with ones that had dry rotted. Logic does seem to suggest they can't be original.
 
Wow. Thanks so much, Dan. I am assuming they made the top and bottom the same to save labor, and at this point I'm thinking yours are originals, since Mustang Mark says his original foams are still good; they probably last better since they're out of the sunlight and don't get much air circulation.

I really appreciate the help!!!
 
On second thought. I just saw a picture of a pair of 846Us that ended on that auction site and sure enough the same foam is in em.
 
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