Hallicrafters Model R-12 Console Speaker (1940)

     

Many Hallicrafters SX-28 owners are familiar with the metal PM-23 speaker like the one shown below. A much rarer bird is the Hallicrafters console speaker, shown in a 1940 QST Magazine ad.

  

Housed in gray wooden cabinets, the console speakers featured a bass reflex design and superior audio quality. The ad gives their basic dimensions. The R-12 was big enough to serve as a stand for the SX-28, while the smaller R-8 was suitable for a table or wall mounting.

In 2009, I was contacted by a collector familiar with the the Western Historic Radio Museum in Virginia City, Nevada. The museum owns an R-12, and Henry Rogers was kind enough to provide detailed photos, measurements, and notes for anyone who is interested in building a replica.

Henry's notes and photographs appear below.

This R-12 is an original example. I had to restore it because it had
been stored in a basement for years and was on the verge of falling
apart. I had to disassemble the box and reglue most of the soft wood
veneer. I repainted the box, too. I matched the paint to a part of 
the "h" grille piece that was protected and that provided an accurate
color match. Hallicrafters called the color "gunmetal."

The original speaker is a Jensen "Wide-Range Dynamic" (read PM) 12"
speaker painted dark green. The speaker has a matching transformer
to provide 8 ohms Z for the speaker and 5000 ohms Z to the SX-28.

Overall cabinet dimensions: H: 29 3/4"  W: 22 1/4"  D: 16"

Front panel thickness: 7/8". All other panels: 3/4"

Back, top and bottom: plywood. Side panels: solid (probably pine).

        

The round speaker opening is 10" in diameter. The "h" grille is 1/4"
plywood. Height is 14" from cabinet bottom to lower speaker opening.

     

The wire screen grille was originally "flocked" with a champagne or 
beige colored felt. I think the felt "blew" off with use, since every 
R-12 photo I've seen appears to be just screens now. When disassembling 
my R-12, I found that where the screens were protected by how they
mount, the flocking was still present and in good shape.

The rectangular reflex port is 11" x 5 1/8". Height from cabinet bottom
to bottom of the reflex port is 6 3/8".

  

The front cut-outs for the speaker and the reflex port are pretty rough,
since they are cut out of the plywood front.

I think Jensen used high quality marine-type plywood which has a lot 
of laminations and therefore gives a fairly good finish. The only screws 
that hold anything together are the screws for the back. All of the other
pieces are held together with the clamps that fit into incised slots and
are held to the opposite piece with a wood screw.

The clamp construction was to allow the speaker to be shipped 
disassembled. Replicas could be built with glue blocks instead.

18 clamps total: 6 bottom, 6 top and 6 front.

           

The back of the R-12 is a solid plywood piece with a small 1/2" hole in 
the center of the back for the speaker cable to exit. The speaker cable 
is black AC line cord.

Back screws are 1 1/2" wood screws, oval head. Back wood pieces are 3/4" 
square material. The back screws into these pieces.

Front wood piece is 1" x 3/4" material.

Incise: 1/8" width.

The front "waterfall" treatment of the top edge: that is a solid piece
of wood and you can see in the photos the seams from the pieces that 
were glued together to make it. It would not have had a suitable 
appearance if it had been made out of plywood or lumbercore. This 
solid wood piece could be shaped and would have the correct curve to 
the waterfall front. With the ogee that is on the sides, since they
are lumbercore and edgewise, that works out fine for that finish.

  

You can operate the SX-28 receiver at loud volume with it sitting
on top of the R-12, with no microphonics. As for the reflex port size,
the R-12 is very similar to many of the Jensen Bass Reflex boxes 
that were available in the late 1930s through the 1940s. The R-12
was built especially for Hallicrafters and has some exterior box 
changes to match the SX-28, but the basic interior design is just 
like other Jensen bass-reflex boxes of the day.

The history of this R-12/SX-28 combo: It was sold to W6ANX, Theron 
Woods of Los Angeles, CA in 1940, along with the SX-28 receiver 
SN H-130170. Both the receiver and the speaker were found in Woods' 
basement at his home in Auburn, CA in the late 1990s. I have 
rebuilt the SX-28 and use it several times a week, listening to 
various types of signals, from AM-BC to AM-SW to hams. Audio 
reproduction is impressive with lots of bass.

Hope this gives you enough data to build some replica R-12s. They 
are really fabulous sounding speakers when driven by the SX-28.

Henry Rogers

Thanks again to Henry for this information, and to Bill Ramsey for putting me in touch with the museum. If anyone builds a replica using these instructions, please email me. It would be fun to add your photo to this article!

©1995-2017 Philip I. Nelson, all rights reserved