My Zenith Circle of Sound Project

I acquired a pair of these for free from the side of the road and wanted them to sound better.

My first step was to reseal the cabinets, as the bottoms have holes in them. After that, I am thinking car stereo coaxial.

BTW, the bodies are cardboard (think Sonotube) with steel rings top and bottom for strength. Legs are held on with screws through the cardboard. Bottom is pressboard. Top is a plastic screen material. "Top hat" is pressboard. Diffuser cone is hard plastic. All covered in woodgrain vinyl.

Pretty cool to look at, let's see how they can sound...
 
OK, step one: get them back to factory condition.
That was easy, I just cleaned them out and made new bottoms for them to reseal the cabinets.

Result: medíocre. Not great, but better than I expected. Very highs and lows are not there, but the mid is OK. My Mac 4100 has a built in EQ and variable loudness. If I crank the 10K EQ and crank the Loudness to boost the bass, they are not bad at all.They pull quite a bit of power, 3 W at mid volume which surprised me; not efficient at all. (This is what my AR-3s draw at a much louder volume.)

Next step: better drivers.
 
OK, better drivers have been found. I was given a pair of Leviton SGC-65 in-ceiling speakers that I forgot about, but tripped over on Friday. Hmmm, they are coaxial, with a small crossover and are 6.5" across.

I pulled one out and they are a perfect replacement size, even the screw holes line up perfectly. Only issue is that the tweeter sticks out quite a bit, so I made some spacers. I also added some proper speaker terminals I scrounged up. Here are some picts with more info.


What I used:
IMG_0592.JPG

IMG_0593.JPG

The tweeter stick out too far to clear the grille, so I made some spacersIMG_0594.JPG

Mounted in the enclosure:
IMG_0595.JPG

Reinstalled the insulation:
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Repaired the original bottom, added proper terminals and painted it:
IMG_0598.JPG

Next stop is to test them, but will have to do that later. I'll report back.
 
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Had a chance to test them out - not too bad, about what you'd expect for bass, but the tweeter actually sounds pretty good.

I boost the bass with the Loudness on the receiver, and they actually sound pretty good.
 
Good on you for preserving these classic pieces of Americana, even if they were more marketing than engineering. I always thought they were cool looking. I was going to suggest a Bose drivers since they can sound pretty good in the right setting.
 
I was going to suggest a Bose drivers since they can sound pretty good in the right setting.

Not a bad idea. Can not think of a Bose coaxial off the top of my head, but they do know how to make small speakers sound pretty good.

I am listening to the Soggy Po' Boys first album on them not and am not missing my other speakers as much as I thought I would.
 
I don't know of any coax Bose drivers but full range the highs still seem to come out ok from their speakers.
 
LOL ...seriously "Hard Core!" Do you have it all put back together?? If it looks good (the same) and it sounds good and it seems it does. Add "Bluetooth" to it and put on it ... Etsy.com, if you do want to sell it??

It is a good size and it looks retro cool and if I can use my "Phone" with it??? It has a new market it never had when new! Just a thought. :)
 
Well, they do not have internal amps like BT speakers do, so it would have to run an external amp.

No plans on marketing them, just a for-fun project.
 
If it has an aux input, you have your "BT" solution! Even I can do that! We'd like to see a "pic' of it all put back together ... it "sounds" (no pun intended) cool! :)
 
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