Speaker build

Tube Radio

Super Member
I recently got these speakers from an Emerson console radio.

One Jensen P15S woofer
Three Jensen 5" cone tweeters

I made up a temporary two way crossover based on the frequency the tweeter was crossed over at and installed them temporarily in a cardboard box with the tweeters in a horizontal row at the top of the front of the box.

The speakers sounded quite good with decent bass response being driven by one channel of a FiiO A1 14WPC amp and I know the bass response will be better in a proper cabinet.

What I would like to do is have a proper open back cabinet built for the speakers.

What would the deminsions of the cabinet need to be, what should the cabinet be made of and should I keep the tweeters in a horizontal row or is there some other arrangement of the tweeters that would sound better?

Here's the crossover.

Impedances were found using the Dayton Audio DATS speaker tester. Also used it to make the inductor by unwinding a larger inductor until I reached the right inductance.

The crossover components are in the negative side because when I wired the speakers up I wasn't sure of the polarity of the woofer and a battery test looking for which direction the cone moved showed me I had the positive and negative reversed and it was simpler to just reverse the wires to the amp versus desoldering and resoldering the crossover components.

Jensen speaker crossover.jpg

I did notice a slight harshness to the upper midrange which could just be the woofer itself reproducing higher frequencies it cannot reproduce properly, but the cone did have a few small tears when I tested it that I later fixed with Elmer's school glue since the cone is paper.

I might connect the audio generator to the amp tonight and see if I can find the upper midrange frequency that is sounding harsh. I could fix it by lowering the crossover frequency, but the tweeters sound so good crossed over so high to the point where I more than likely wont need a dome tweeter for the upper treble above 12KHz and I don't really want to risk mucking up the sound by lowering the crossover frequency.

For the time being this will most likely be used with a Sylvania RM-300X radio until I find another set of these speakers and make another cabinet at which point they may replace my KLH 22A speakers in my smaller stereo system provided they sound better than the KLH speakers.
 
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