Beginning the RCA LC-1A adventure.

I hope you'll forgive a little backstory here, but it's a necessary in getting to how I found a speaker I thought to be near extinction...

A month back I was at work on a Sunday afternoon (as sometimes happens) and decided to kill a few minutes running a set of searches I run from time-to-time. This one kicked back a few results that made me spit out my drink - RCA LC-1A drivers on craigslist at prices that seemed to be missing a zero behind them. A LC-1A (with the humps) listed in the collectible section of CL, and its predecessor, the MI-11411, listed under musical instruments. They'd been up for 10 days. Had I missed something, or had this somehow flown under the radar?

The downside: the speakers were a few states over, in a suburb of Kansas City. Despite the distance between them and myself I contacted the seller and found out they were still available, somehow. I called a buddy from college who lived nearby and asked if he'd be willing to help me out - he was. I Venmo'd him the cash and prayed this thing worked out.

I biting my nails for half a week, but he got them.

As i wasn't sure of their exact condition, I didn't think it wise to ship them. And I certainly didn't want to ask anything more of my friend. I would just have to wait until I'd have time to go and get them.


I got them last week.

The good: they work. The cones are intact, but they'll need some work. The LC-1A is the worse off, sadly. It's missing one of its famous bumps, the others are pushed in slightly. It looks like part of the cone had water damage at some point and the paper surround wlll need to be reinforced. The single capacitor, acting in lieu of a crossover, is bad - a new cap of the same value is arriving today. The MI-11411 is in much better condition. It has a slight tear in the cone at the surround, but is in fantastic condition otherwise.

I'll be working with a local shop that handles speaker repairs on finding solutions for preserving the original cones. If not, I'll reach out to some gurus I've had contact with to see if they have any advise.


Throughout the past week, I've taken time to listen to the MI-11411, treating it gingerly as I don't want to put any further wear on the existing tear. Feeding it off the 16-ohm tap of one of my Altec 128B's, I can hear already why this speaker is as sought out as it is. Two records in particular have encouraged me to put in the work to get these speakers right - Frank Proffit's Frank Proffit of Reese, North Carolina (Folkways FSA-1) and Dock Boggs Legendary Singer & Banjo Player (Folkways FA-2351). I've listened to these albums on a few different speakers and have never felt that I've heard them correctly.

Even through one of these speakers sitting on the ground there's life and presence in Frank Proffit's voice that belies the age and quality of the recording. Dock Boggs, too, has reality given back to him.

Subjective language, sure, but they're my ears.

I'll update this thread as I'm able to devote time and funds towards the preservation of these speakers and cabinets I'll build for them.

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Redboy

Knobophobe
I don't mind a preamble, when the story's this good... I'll be following along because I think these RCA drivers are just so cool!

There's a fella on AK who recently built a pair of cabinets for his, based on the originals. Have you seen them?
 

Audionut

Next Round Is On Me
Signed up! Should be interesting how you source or make more of those cones; maybe something like papier-mâché?
 

gable

Senior Member
I think the back-story adds charm to finds like these. LC1-A's are very high on my list to try and acquire one day. I've heard they are very, very special.

Excited to follow your adventures with them.

Cheers,
Gable
 
I don't mind a preamble, when the story's this good... I'll be following along because I think these RCA drivers are just so cool!

There's a fella on AK who recently built a pair of cabinets for his, based on the originals. Have you seen them?
I don't know if I've seen those yet, though I've seen several different cabinet designs that RCA put out for these. I'm waiting until I have enough time to be bored so I can take a chance at producing a digital model for this cabinet, just to gauge the difficulty of building one for real:

http://www.itishifi.com/2010/03/harry-olson-folded-horn-1956.html?m=1
 

gable

Senior Member
This pair belongs to a friend and the original Art Deco-style cabs are loaded with the earlier smooth cone MI-11411s. They sound great!
I love the style of those cabinets. I've seen several different versions and they all have great esthetics.

Cheers,
Gable
 

gable

Senior Member
I don't know if I've seen those yet, though I've seen several different cabinet designs that RCA put out for these. I'm waiting until I have enough time to be bored so I can take a chance at producing a digital model for this cabinet, just to gauge the difficulty of building one for real:

http://www.itishifi.com/2010/03/harry-olson-folded-horn-1956.html?m=1
Looking over the images I don't think it would be _too_ complex of a build. It's not going to be an easy one per se, but all in all I think it's fairly straightforward.

For what it's worth, I think modeling in sketchup or similar to work out bevels and miters of each panel is a great idea. I will say from experience that you typically will need to adjust ever so slightly when transferring 3d model to reality. What I've done in the past that's worked well is to use the model to help you create the first one, typically from inexpensive material, like horrible-awful-terrible-gross-dusty-heavy-stupid MDF. That is it's official name, btw.

As you build the first prototype I suggest building any jigs, sleds, etc to make replication easier and most importantly, consistent.

In short, I say go for it!

Cheers,
Gable
 
Congrats on acquiring very fine speakers!

This pair belongs to a friend and the original Art Deco-style cabs are loaded with the earlier smooth cone MI-11411s. They sound great!
There's an exhibit currently mounted at the Dallas Museum of Art that's had me wondering how audio gear has remained as a blind spot within the space of design criticism - link here if you're curious: https://www.dma.org/art/exhibitions/cult-machine-precisionism-and-american-art

I have to wonder who it was at RCA that gave these designs the little bit of flourish that visually makes them sing...

I'm going to spend some time around Christmas building your open baffle design - I'll report back on how this speaker responds to that application.
 
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Looking over the images I don't think it would be _too_ complex of a build. It's not going to be an easy one per se, but all in all I think it's fairly straightforward.

For what it's worth, I think modeling in sketchup or similar to work out bevels and miters of each panel is a great idea. I will say from experience that you typically will need to adjust ever so slightly when transferring 3d model to reality. What I've done in the past that's worked well is to use the model to help you create the first one, typically from inexpensive material, like horrible-awful-terrible-gross-dusty-heavy-stupid MDF. That is it's official name, btw.

As you build the first prototype I suggest building any jigs, sleds, etc to make replication easier and most importantly, consistent.

In short, I say go for it!

Cheers,
Gable
That's exactly the process I think I'd be putting myself through. I'm fortunate to have some friends with very well equipped shops so building it would not be an impossible task.

The speakers are going through a triage process at the moment. Sadly, I might only need to build one cabinet - the LC-1A might have an open voice coil, and its cone and surround have some water damage which would require some solution which will require some consultation. I'm deaf in one ear so it's not an absolute loss - I might just have a great mono setup until the LC-1A can be fully revived.
 

je2a3

Junior Member
There's an exhibit currently mounted at the Dallas Museum of Art that's had me wondering how audio gear has remained as a blind spot within the space of design criticism - link here if you're curious: https://www.dma.org/art/exhibitions/cult-machine-precisionism-and-american-art

I have to wonder who it was at RCA that gave these designs the little bit of flourish that visually makes them sing...
Very interesting programs and exhibitions!

Many unsung artisans and engineers at RCA, WE, Altec, etc. during that era whose ears were exposed to live un-amplified classical and jazz music.

I'm going to spend some time around Christmas building your open baffle design - I'll report back on how this speaker responds to that application.
The owner of this pair has a spare pair of LC-1s which were tried in the OB, less bass but no cabinet coloration. It's always a compromise.
 
In the past few months I've done what I can with these speakers.

The non-hump MI-11411 received some care from a speaker repair shop here in Dallas, Freeman-Tuell. Metal shavings had built up around the spider and were removed - it doesn't appear that this had damaged the voice coil, fortunately. Some other separation is occurring, however, at the juncture of the tweeter cone and the bass cone - during playback this produces a slight click, which I imagine would only worsen over time with further playback.

Disappointment, there.

The (with-humps) MI-11411A's tweeter has an open voice coil. Simple as that.

I've reached out to Jonathan Weiss, as he's helped me in the past with other RCA gear, to see if he knows of any extant replacement parts for these speakers. I might reach out to Steve Schell if I can find some contact info, as he seems to be the other expert in the world of RCA equipment.

This is sort of a shot in the dark, but might anyone here know if replacement parts, original or otherwise, for these? I would love to have a functional pair; if that isn't possible these might have to go on to another hopeful soul.,,
 
. . . I might reach out to Steve Schell if I can find some contact info, as he seems to be the other expert in the world of RCA equipment.
I chatted with Steve Schell a long time ago when he was building Cogent field coil drivers and have an old email address. It's the same one listed on the Piano Tuners Guild, which can be found here: Steve Schell contact info
Don't know if it's still current but worth a shot.

---Gary
 
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