Tom Danley mods for Altec VOT A7?

[mcds]

I understand Tom Danley once proposed some mods to the A7 which are supposed to improve the sound greatly. I couldn't find anything on the net, and paging Tom on AA brought no result.

Anybody happen to know where I could find further info?

[louped garouv]

there's an old Sound Practices article by Jim Dickinson that you may want to search out also....


if you can still buy the Sound Practices Archive CD on Ebay, I thought it worth the admission price....

[mcds]

there's an old Sound Practices article by Jim Dickinson that you may want to search out also....


if you can still buy the Sound Practices Archive CD on Ebay, I thought it worth the admission price....

Thanks, I'm aware of the Sound Practices article as I have a full collection of the mag. However, according to an old thread on this very forum, Tom Danley said somewhere that his mods take several hundred degrees of phase distortion out of the design, an aspect which is not covered in the SP article.

[JBLRaiser]

Thanks, I'm aware of the Sound Practices article as I have a full collection of the mag. However, according to an old thread on this very forum, Tom Danley said somewhere that his mods take several hundred degrees of phase distortion out of the design, an aspect which is not covered in the SP article.

what do you need to know?

[mcds]

Here's the info that can be found on the Altec User Board:

A-7 mods

Replace stock drivers with JBL-2226 and BMS 4550.

Replace lower vent panel with one having 4 , 4 inch dia ports, 5 inches long.
Pic #60

Reinforce 15” horn flares, glued in with construction adhesive not wood glue or epoxy.
I used boards which were 5 ½ inches by 12 inches with one side cut to a 20 degree angle to better mate with the horn flare.. These are way too live.
Shown in pic # 62
Before and after is shown in measurement, gets rid of a few dips.

Optional, it wouldn’t hurt to put a 2X2 diagonally on the lower cavity side walls with a 2X2 added to tie the sides (from one side to the other) together.
I would use construction glue to adhere the 2X2’s to the walls and when dry, use screws to attach the cross brace.

Apply damping to the under side of the final bell of the 511 (not visible).
Mount the horn on the rear side of the wood, setting it back from stock.

Mount the 15’s with an extra front gasket for clearance at Xmax.

Use foam tape to seal all removable panels and replace the wood screws with 1 5/8 drywall screws.

Drizzle some extra glue at the front edge of the flare on the interior (the glue joint at the front where the bent plywood attaches. Use that gorilla glue (polyurethane) for this as it fills gaps. On this one there was a gap in the wood (on the inside).

Remove and remount the horn mounting board, remount 2 ¾ inches rearward and use the foam tape under it (which dampens the box top panel).

I'd love to see the pics, of course, but most importantly, I can't imagine that TD did not make any suggestions for the crossover.

Also, which version of the 2226? Not sure I'd go with the BMS, but TD usually knows what he's talking about.

[Zilch]

Not sure I'd go with the BMS, but TD usually knows what he's talking about.

Unity horns are built with BMS 4550s, I do believe....

[Russellc]

Here's the info that can be found on the Altec User Board:



I'd love to see the pics, of course, but most importantly, I can't imagine that TD did not make any suggestions for the crossover.

Also, which version of the 2226? Not sure I'd go with the BMS, but TD usually knows what he's talking about.

Well I can tell you one thing, when you hold a 2226H or 2225H driver up to the hole in my 828 A-7 cabs, you're going to need a hole shrinker! Driver aint quite as big as the original I have, 416 8C and 515 8G anyway......

Russellc