1" Horn Flares - educate me!

 I'm about to complete a design for a 12" + 1" compression driver (both Celestion) and currently have a DAS BC-1 horn in the box. The horn is not bad but I'm thinking there might be something better available. By 'better', I mean a smoother frequency response and a more natural sound.

The last time I tested a bunch of 1" horns was about 15 years ago. I hear the technology has moved on a bit since then. I'm particularly intrigued by the JBL Econowave-type horns, which are very inexpensive. The only way I can try one of these is to buy one - so I thought I'd canvass opinions first.

I need a CD 90 x 40 (ideally), 12" wide (approx.) and ideally with a screw connection to suit my compression drivers (are adapters 'bad'?). Crossover is 4th order at 1k6.

Thanks b grade, but that's an exponential horn and I really need a constant directivity-style response. The speakers are going to be used on their own most of the time as a band PA.

Has anyone used the JBL Progressive Transition waveguides? Are they an improvement on older CD horns? They're available at very low cost in the States but can you get them in the UK?


Edited by stevie - 07 December 2012 at 9:48pm

Cheers, ceharden. Maybe it's a mismatch between the compression driver and the horn, but the frequency response I'm starting off with isn't very pretty (not just the HF rolloff, which is not normally a problem). I've used various methods of correcting this and at one stage had two notch filters in the circuit, which is ridiculous. I would prefer a horn that gives me a smoother response.

After two weeks of fiddling with the x-over I seem to have got something that works. The only downside is that the electrical phase rises to around 70 degrees at 2kHz. Do you think it will matter?

Edit: the crossover is passive.


Edited by stevie - 08 December 2012 at 11:11am

Re: "The only downside is that the electrical phase rises to around 70 degrees at 2kHz. Do you think it will matter?"

Can you be more specific on this please?


Mik

Here are the measurements. The frequency response curve is unsmoothed and the sharp dips above 6K are probably grille artefacts. Ignore anything below 200Hz. Drivers are a 4-ohm Celestion TN1230 and a CDX-1 1731 compression driver.

The electrical phase is shown in the impedance curve. What I'm concerned about is the swing to about 70 degrees between 2 and 3kHz, which I believe amplifiers might not like. What say ye?






Edited by stevie - 10 December 2012 at 1:06pm