New project half folded horn.

Datasheet says 45Hz to 4.5kHz and I bet it sux at that high frequency like most woofers do.

I don't understand the enclosure photo in the first post, is there a diagram or something with the completed design?

Its the 12-500LF not the 12-500.
It goes to 5KHz according to the pdf on it.

I just scribbled down a rough drawing of the half folded horn.
I got it from one on sale on ebay.
Hopefully my dimensions aren't too far wrong.

I will put up another picture when it has progressed a bit.
There are 3 panels missing from the op to fit yet.


2016-02-25 11:27 pm
Its the 12-500LF not the 12-500.
It goes to 5KHz according to the pdf on it.

You didn't say LF in the OP, here is that data sheet: Sovereign 12500LF DS030513.pdf

The inductance they quote is 2.36 mH at 1kHz which will obviously effect the slew rate at higher voltages and frequencies. You can see in the frequency response chart that it drops off a cliff at 4KHz so the 5kHz claim is most likely a mistake, even at their +/- 6dB spec. (Manufacturers generally quote +/- 3dB for frequency response)

Most speakers have a realistic useful working range of around 2 octaves at decent power.
In a cavity setup like that 5k is dreaming. It'll be interesting what measures look like when you're done.

I will put the sig gen on it once it is built and see how it performs.
It will only be by ear though.

I was told a similar story about my full folded horn speakers but they work very well up to mids.

I can see the sound is going to be quite complex.
The sound comes out of the back of the driver into a cavity so there will be lots of reflections from the four holes in the back of the driver and the box.
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You're still not going to get 5kHz out of that 12 without severe beaming & rolloff, especially so with reflective cabinet surfaces & a magnet in the way. There's nothing magical about the design which will extend & widen the driver's useable HF coverage.

I hooked up a sig gen to the speaker.
It works fine up to a few hundred hertz around 400Hz.
It has a peak around 7KHz for some reason.

What is odd is it sounds ok with music.
The tops aren't too bad.

I will be using it with a dual tweeter so that should even things up a bit.