Old Console drivers in open baffles

[Geoff H]

Hi GM, I noticed your reference to Cohen. Would that be Abraham? I have his "Hi-Fi Loudspeakers and Enclosures" A great reference. The covers are falling off. I have an idea though. I'll check out the 2nd hand book shops. I once saw a book that had black hard covers, and gold leaf titled "Old Testament" and rebind Cohen's words of wisdom. LOL

Once Bob gets away from his keyboard and cuts those baffles he could kick of a new thread "Restoring Toobs"

Cheers,
Geoff

[Smokehouse Bob]

Speaking of cutting, Geoff, do you (or anyone else) have any tips on a cutter or technique for making a nice, round hole in the sheet plywood?
I've never had to produce a nice hole that large before. Is the thickness of the ply (say 3/4 versus 1/2 inch) a big variable to consider? I realize MDF is much more dense than ply, so that may make that choice easy.

[Dumbass]

You could make a dead-simple circle jig for a jigsaw.

The best results come from routering, I believe.

[renfrow]

If you're mounting the speakers on the front of the baffle, just draw a circle of the appropriate diameter and free hand it with a jig saw. You're steady enough to be within a 1/16 of an inch. Any deviations from the line are going to be covered by the rim of the speaker, and can tolerate much more than 1/16 of an inch . Been there, done that .

Tom.

[Geoff H]

Bob, as the others say, jig saw.

I draw 2 circles, one for the hole, and one for the PCD of the mounting bolts. Drill the mounting holes, then cut the circle. Not so critical with ply or mdf, but chipboard is fragile if the circle gets to close to the mounting holes.

Just take your time with the big circle. Mount the driver from behind, and if you can, chamfer the circle, leaving enough timber near the mounting holes. Let us know what they sound like.

Geoff

[Smokehouse Bob]

Originally posted by Geoff H
Bob, as the others say, jig saw.

I draw 2 circles, one for the hole, and one for the PCD of the mounting bolts. Drill the mounting holes, then cut the circle. Not so critical with ply or mdf, but chipboard is fragile if the circle gets to close to the mounting holes.

Just take your time with the big circle. Mount the driver from behind, and if you can, chamfer the circle, leaving enough timber near the mounting holes. Let us know what they sound like.

Geoff

Okay, easy enough to follow. Rear mount and cham on the front edge should be nice. My hands aren't as steady with the jig saw as they should be, so that'll be the real challenge. Excuse my ignorance, but what's a PCD?

[Geoff H]

Pitch Circle Diameter = the dia of mounting screws / bolts pattern

[Smokehouse Bob]

"I see" said the blind man! Thanks!

[no xo]

I just read this thread today and it is interesting to me. A couple months ago a friend gave me the "guts" from an old Magnavox console. There is a vertical mount tubed reciever, 2 15" drivers with small magnets, that were firing out of the sides of the console and 2 mid-hf horns and drivers ( small driver, both horn and driver painted orange), and Xovers. Everything look to be in good condition, but I don`t know what to do with these. Anybody in the Chicago area, who reads this forum, would be welcome to have them if picked locally. I don`t have a digital camera or I would post a pic of the stuff. If you`re interested let me know.

[GM]

Greets!

Originally posted by Smokehouse Bob
Hi ya GM! I'm up in Woodstock, nice to hear from a local and an interesting history you have with these and other audio.

I use to play at racing over your way back when it was 'God's Country'. Good to know there's another one of 'us' ~locally, we're few and far between AFAIK, with only a few others scattered from Tyrone to around the corner from me coming to mind at the moment. When we had the few Atlanta DIY Meets, most of the relatively few 'FR' folks that attended were well away from metro Atlanta, mostly from Tn. and S.C.. Small cone/dome two ways rule around here, so the vast majority of local DIYers hang over on the MAD and PE boards.

Originally posted by Geoff H
Hi GM, I noticed your reference to Cohen. Would that be Abraham? I have his "Hi-Fi Loudspeakers and Enclosures" A great reference. The covers are falling off. I have an idea though. I'll check out the 2nd hand book shops. I once saw a book that had black hard covers, and gold leaf titled "Old Testament" and rebind Cohen's words of wisdom. LOL

Once Bob gets away from his keyboard and cuts those baffles he could kick of a new thread "Restoring Toobs"

Cheers,
Geoff

Yep, my hard bound 1st edition 'bit the dust' about the time the 2nd edition went to paperback, which is now held together with 3" wide book binding tape and mass quantities of PVA glue. As far as it goes, it's a timeless reference for the DIYer, as is Badmaieff's/Davis's 'How To Build Speaker Enclosures', especially for folks who are rooted in tube era systems.

GM