Lets restore some RCA PRO-X880AV's w/ Linaeum Tweeters + Fiber Woofers

[QUiKSR20]

Recently came across a marketplace ad for free speakers, Thinking these were Minimus 7s which I love I ran and grabbed them.
When I saw them in person they were labeled RCA 40-5035 and larger. Free is for me so I still grabbed them and when I got home
I googled them I came across an ad that showed them with these odd looking tweeters ( Linaeum ) and yellow fiber woven woofer cones.

Based on the shack catalogs they look to be from 2002 ( Featured on page 175 )

2002 Radio Shack Catalog

Flip through the 2002 Radio Shack catalog containing: stereo systems, tape players, radios, computers, scanners, gaming devices, HAM radios, TVs & VCRs, phones, electronics, test equipment & more!

www.radioshackcatalogs.com

These speakers are very similar to Minimus 77 / Optimus 77's with a familiar metal we see on most Minimus speaker lines. Like most of the
later generations from RCA these are ported. After popping the grills off and cleaning them I realized the foam was a gooey disintegrated mess.

Internally there is some sound deadening material and a crossover that has one Nichicon Film Capacitor ( forgot to grab the specs but a recap wont help here ).
These metal cabinets can usually be improved by lining the walls with Dynamat or equivalent sound deadening material but I didnt have any on hand.

For most of my refoams I call Simply speakers for parts but they said they didnt have the foam so I reached out to Midwest speaker who asked me
to send measurements... Once confirmed they recommended the kit below ( they have always come thru for me on non standard speakers ).

Optimus 5″ Refoam Kit (F4-2) | Midwest Speaker Repair

www.midwestspeakerrepair.com

Prep - ( I scrapped most off with my finger / plastic spudger tool and cleaned the cone with non acetone nail polish remover ( alcohol may work too ymmv ).



Found a pro-tip in a previous post that said "LEAVE THE CARDBOARD RING" on the outer edge which helps with the new foam adhere ( great tip )
Post link - https://audiokarma.org/forums/index...ter-equipped-optimus-and-rca-speakers.637756/



New foams should be here this week and ill tackle the installation and update the thread.

 

[jimreeves]

Great find! Those are really fun speakers.

 

[swechsler]

Hmm. I used to have a couple of pairs of Optimus Pro-LX4, which was somewhat similar, although with a smaller woofer in a wood cabinet. But then I looked a little closer and noticed that the Linaeum tweeter in the X880 is different from the monopole Linaeums I've seen in other RS speakers. Note that the earlier tweeter has only about 1/4 of a cylinder for each half of the diaphragm (below) while this one seems to have a half cylinder on each side. In fact it more closely resembles the tweeters sold on Linaeum's own speakers.

BTW, it looks like the Lineaum tweeter and its inventor are still around, at a company named MC AudioTech. They are not cheap.

 

[QUiKSR20]

Hmm. I used to have a couple of pairs of Optimus Pro-LX4, which was somewhat similar, although with a smaller woofer in a wood cabinet. But then I looked a little closer and noticed that the Linaeum tweeter in the X880 is different from the monopole Linaeums I've seen in other RS speakers. Note that the earlier tweeter has only about 1/4 of a cylinder for each half of the diaphragm (below) while this one seems to have a half cylinder on each side. In fact it more closely resembles the tweeters sold on Linaeum's own speakers.

BTW, it looks like the Lineaum tweeter and its inventor are still around, at a company named MC AudioTech. They are not cheap.

Thanks for sharing the above info!

I was aware of the models with the tweeters on top such as the RCA 40-5007 aka Pro LX5 but never saw them incorporated in these models.
The wooden ones you posted look cool and ill take a look at that MC Audiotech link, The only link I found was this - https://www.hifianswers.com/2023/03/linaeum-corporation-what-happened/

I have a bunch of better small speakers but I figured why not bring these back to life for a fun weekend project + I hear they sound pretty good for what they are.

 

[QUiKSR20]

Foams arrived and I was able to assemble, it wasn't the easiest with these fiber cones but I think its going to turn out good enough for basic speakers.



Just waiting for the glue to dry and then I can center the voice coil via feel and or a small test tone, The glue dries clear and wont be that visible when done.

 

[stereofanboy]

Having the disassembled speakers in hand, could you follow Srinath's reasoning on attaching on top of the trim rings? I don't quite get it.

 

[QUiKSR20]

I left in in place per his notes but honestly im not sure what he means about the foam not getting squeezed.. The surround is no where near the screws.
What I can say though is by leaving it, it lets the foam rest on a nice level edge vs being pulled down lower.. Regardless I glued it to the top and now that
it dried it looks and works perfect.

Ill post pics and a demo video in the morning, they are done and sound great ( for what they are ).