Things don't quite work out like this. What one wants in a woofer is generally a narrower directivity, not a wider one and this is very hard to achieve in practice.
Earl, one thing I've wondered about when you said you had tested coaxials and found them lacking, do you mean coaxials with built in waveguides this too? Or do you only mean conventional "use woofer cone as waveguide" coaxials?
Couldn't a steeper crossover solve that problem?
I though you were going active with your new series?
I have a BMS 4538 1" which could sit pretty in a large OSWG, while I'm waiting for my larger 2" drivers to arrive I may try and knock up a faceted OSWG, if I make the 'petals' from thick enough stock, I have some 1.5" cherry, there may be enough material to turn them round on the inside.
Has anyone tried continuing the round over of the mouth of the horn back on itself ala JMLC?
If these aren't to be mounted on a baffle, then would it be silly not too?
Has anyone tried continuing the round over of the mouth of the horn back on itself ala JMLC?
If these aren't to be mounted on a baffle, then would it be silly not too?
After multisubs, next logical step would be DSP. Something similar to JBL M2.
I expected eliptical waveguide though, when i read that everything will be different few days earlier - but let's wait and see what Mr Earl prepared for us
I'm a big fan of his WG concept.
EDIT:
Something on topic - not OB though. Me and two of my friends making test cabinets for some waveguides with DE250 and Beyma SM115/K (aka 15K200)
http://s7.postimg.org/r873o30a3/image.jpg
An externally hosted image should be here but it was not working when we last tested it.
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Using a baffle is best, but if you don't then taking the radius all the back is best.
After multisubs, next logical step would be DSP. Something similar to JBL M2.
I expected eliptical waveguide though, when i read that everything will be different few days earlier - but let's wait and see what Mr Earl prepared for us
I'm a big fan of his WG concept.
I built an elliptical waveguide. It had tradeoffs just as you would expect. I did not find the trade offs worthwhile. I have only been using DSP lately. The MiniDSP is a very good solution to the crossover problem. Back in the days when these boxes cost thousands, then several hundred, the cost-benefit was not there. But in volume the miniDSP is extremely attractive.
If the problem you get at 1500Hz is caused by the woofer narrowing directivity above your crossover point then a steeper slope would certainly attenuate its effect by 1500Hz...
I don't think that it's that simple. At least changing the slopes did not actually improve the result in the design. Remember that changing the slopes changes the phase which is a critical part of the polar response. The crossover point is well below 1500 Hz so the narrowing is more likely a result of the waveguide than the woofer, but interactions between the two were certainly a factor.
That's awesome! I always thought the 12" is a good size for the average audiophile.
For the life of me I can't figure out why the car audio guys spend $500 on DSP boxes. MiniDSP does so much for so little cost and is so easy to use, it makes it really hard to get enthused about ever doing passive crossovers again.
I've been considering a bit of a 'hybrid' approach, due to the noise of the MiniDSP. Basically use a resistor and a cap on the compression driver to lower the efficiency, which should lower the noise floor. Right now the noise floor with a compression driver and miniDSP is so loud it's nearly unusable for me.
Looks like I have some reading to do:
http://www.diyaudio.com/forums/minidsp/212592-minidsp-high-efficiency-speakers-noise.html
Over on Diyma there have been similar complaints
I had a customer who complained about noise in his crossover. Turns out that he was using amps that had no gain controls. By simply dropping the MiniDSP output gain by 10 dB the noise went away.
Basically the MiniDSP has input AND output gains and these have to be set correctly for your particular situation. Keep lowering the gains until - usually the output gain, until with your volume control all the way up you are at the loudest you will ever listen. Start with -10 dB gain on the input side.
The MiniDSP is not really noisy, but most people are not used to two gain settings in addition to their master volume control and this can get the system gains all out of whack.
Power amps should ALWAYS have gain controls, but with audiophool amps this is not always true.
Basically the MiniDSP has input AND output gains and these have to be set correctly for your particular situation. Keep lowering the gains until - usually the output gain, until with your volume control all the way up you are at the loudest you will ever listen. Start with -10 dB gain on the input side.
The MiniDSP is not really noisy, but most people are not used to two gain settings in addition to their master volume control and this can get the system gains all out of whack.
Power amps should ALWAYS have gain controls, but with audiophool amps this is not always true.
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