AK Design Collaborative - Insignia-Class Economy Speakers (a.k.a Indignia)

RayW said:

Adjust-o-bass. :thmbsp:



Yeah, you want everything flush on the front if you can get it. Rounded edges are even better.



I usually set it up so the mounting screws line up somehow on the front and just cut the terminal access where that puts it.



Yeah, the ones I've done have all been buttoned up and XO, terminals, etc. were done through the driver hole.

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Ray, how do you do those little grey quotes in your posts?

Russellc

By using the quote tags. QUOTE and /QUOTE both encased in brackets.

Russellc said:

Ray, how do you do those little grey quotes in your posts?

Russellc

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Magic.

Newman nailed it. I'm an old school geek who still knows a bunch of html tags. I'd rather type a few characters than drive all over the screen with a mouse any day.

RayW said:

Magic.

Newman nailed it. I'm an old school geek who still knows a bunch of html tags. I'd rather type a few characters than drive all over the screen with a mouse any day.

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Or you can cheat and used the "go advanced" feature of the reply box. See the little cartoon bubble thingy above the box I'm typing in?

Type some text, highlight it, then clickthe bubble

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There, you did quotes!

The multiquote feature is cool too....

See this page for cool editing features for forum messages

specialidiot said:

Or you can cheat and used the "go advanced" feature of the reply box. See the little cartoon bubble thingy above the box I'm typing in?



There, you did quotes!

The multiquote feature is cool too

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....

See this page for cool editing features for forum messages

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Thanks guys, I'll dust off my magic wand!

Russellc

jimbofish said:

A-OK (In moon landing mode today:thmbsp

If I get time tonight, I'll post some of the pics of my solutions for cutting the circles w/o the fancy jig.

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Ok now, I think I've got it!

Baffle Milling solutions

After fussing with the circle-cutting jig that I have for my router, it became obvious that it wasn't meant to cut the smallish circles needed for the Indignias. Some hours later, I realized that I could use the 'fly-cutter' in my drill press for the tweeter opening, and Forstner bits for the port hole. Setting the radius to the outer dimension and adjusting the drill press depth stop for the required depth, I moved the the cutter inward after each pass till I reached the through-hole point. Re-adjusted the depth stop to cut all the way through the board. The resulting 'wheel' ended up being used later in the project, but not by design! Careful paring with a sharp chisel removed all the ridges between cuts. The woofer would need some other solution. :scratch2: (Pics 5, 1, 2)

Since my router base is almost exactly 6" and the woofer recess just under 7", it's radius, plus 1/2 the width of the router bit, plus the radius of a center pivot should be able to come pretty close. Using a 1/2" bit and a 1/2" center pivot came to just over 7". By using a 1/2" washer, held down loosely with a flathead wood screw, I was able to micro-adjust the effective diameter of the center point... by loosening the screw, the washer was free to slide inward under the beveled head slightly as the router rotated around it. It actually worked better than expected. :thmbsp: (Pic 3)

I was just planning to use a jigsaw for the cutout, but found the radius needed exactly matched the distance of one of the baseplate screws to the opposite edge of the bit. Inserting the same center screw through the baseplate hole and using a 1/4" through-cutting bit worked really slick... 4 or 5 passes and it was through. A bit of freehand routing removed the remaining material between the two operations. (Pic 4)

The narrow strips of wood on the back of the baffle are to compensate for the rabbet on the front edge of the case, to bring them flush with the front edges. Originally I was going to leave them recessed and make a traditional grill, but took the advice of the designers and set it flush. Now to come up with a new idea for a grill... :scratch2: (Pic 5)

Most Excellent, Jimbo!

I'm sure glad we have Dave and Ray to do the baffle milling for us; I'd be missing some digits if I tried that stuff.

Consider buying the magnetic Indignia grilles from PE, if the size is right. Four flathead screws for them to grab, and you're done.... :thmbsp:

Zilch said:

I'm sure glad we have Dave and Ray to do the baffle milling for us; I'd be missing some digits if I tried that stuff.

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That cutter IS a bit intimidating! Standing rule here at the assembly line is "unless the house is on fire, don't interrupt when machinery is running!" :nono:

Zilch said:

Consider buying the magnetic Indignia grilles from PE, if the size is right. Four flathead screws for them to grab, and you're done.... :thmbsp:

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Buy something that I can make... I don't think so!

jimbofish said:

Buy something that I can make... I don't think so!

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Excellent work, Jimbo! Macgyver would be proud!

I have one more set here that I have to do. If I can find the camera I'll see about documenting the way I do it. Not that it's anything special or creative like Jimbo's adventure, just might be nifty for some to see how theirs were done.

Thanks!

Karma must have been with me that day 'cause everything seemed to just work out perfectly. :yes: Didn't even have to waste a lot of time looking for stuff... "Where the #%&* did that thing go now?"

RayW said:

If I can find the camera I'll see about documenting the way I do it.

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Oh, sure... NOW you show us how!

jimbofish said:

Oh, sure... NOW you show us how!

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Job security.

Cabinet Assembly

Since I was using some old EV-4A cabs that I picked up from the curb, the actual construction was a bit more complicated that it would have been with fresh, new material due to bad veneer, swollen corners, etc. My inspiration was to recycle them into something that would still retain some of their original style, yet work with current design practices.

The baffle is inset in the original rabbet from the front edges of the old cabs. Oddly, the baffle setback on both original EV-4a's was different, thus a 1/4" difference that had to be made up. This turned out to be a minor problem as both had to be shimmed to bring them flush anyway.

The rear panel was dadoed into the sides so I decided to retain that feature. It makes a tight, rigid case that self-aligns when gluing... IF you made all the cuts accurately. :yes: The back panel was cut out from the center of the original in order to preserve the EV-4A sticker.

The round cutouts from the tweeter hole are shown in a couple of the pics. They turned out to be almost a perfect fit for the original terminal hole in the back panel. They're attached to a scrap of 5/16" T&G pine paneling, that's attached to the inside of the cab with 4 screws. The black stuff around them is the original putty that was sealing the woofers on the original EV-4a baffles. Surprisingly, it was still supple after, what, 30-40 years? A little kneading and rolling and it was like new. :yes:

Washed the completed cabs down several times with naphtha and alcohol, and stained with Minwax Early American stain. A coat or two of Minwax Antique Oil will finish off the cabs. lI used some poly batting that the wife had sitting around for at least 10 years to line the interior. Not sure if it's the good kind to use or not, but an easy change if it turns out that it isn't.

Had a few challenges with the crossovers. Seems I forgot to add in the jumper from the + terminal to T+, thus only the woofer was working... and only on one channel! After taking them out, finding the missing jumper and adding it, re-installing them, still only one channel worked! WTF? Removed the offending xover again, tested with DMM... looks ok. Why isn't it working? Luckily, I noticed the meter indicate 'open' for just an instant. Hmmm??? Somethings intermittent. A closer exam with a magnifier turned up the solder joint was moving at the + wire where it connected to a push-in terminal on the board. A quick re-solder and it was solid.:yes:

Managed to only get a half hour or so of listening last night but I'm liking what I hear so far.:thmbsp:

Of Note:

Snell's Indigniaesque K7, a Joe D'Appolito design, rear ported, comes with a port plug for boundary compensation, much as we described earlier in this thread:

http://www.snellacoustics.com/K7Lit_31508.pdf

Indignias submitted for official serial #s ?

Indignia v/EV4A completed and playing!

Complete with battle scars, dents, and scratches!

I was going to look for black screws for the drives, but I'm liking the silver look.
(Forgot to mention that I also re-used the T-nuts from the originals to mount the drivers.)

:tresbon:

And Jimbofish's EV4A Indignias are S/N 33 & 34, handsomely done! :thmbsp:

http://audiokarma.org/forums/showthread.php?p=2269528#post2269528

First time we've seen them horizontally deployed, I believe. How do they sound that way?

Zilch said:

First time we've seen them horizontally deployed, I believe. How do they sound that way?

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Robie uses his horizontally in the nearfield and they sound pretty good there. I'm sure he'll chime in when he catches this.

RayW said:

...
I have one more set here that I have to do. If I can find the camera I'll see about documenting the way I do it. Not that it's anything special or creative like Jimbo's adventure, just might be nifty for some to see how theirs were done.

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That would be great! I'm probably going to get a Router Buddy, unless you have a better suggestion. It would be very helpful to see you do one, even if the gear isn't exactly the same.

RayW said:

Robie uses his horizontally in the nearfield and they sound pretty good there. I'm sure he'll chime in when he catches this.

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They certainly LOOK cool that way....