I think it would be great! Don't expect high output, but done right you probably won't find a speaker that sounds more detailed in de lower mids and lows. You could substitute the coax for a mid and waveguide for smoother response and directivity.
And please delay the drivers on the back instead of those on the front. Also, the upper frequency limit is a bit below for which the distance between front and back driver corresponds to a half wavelength. Something to think about.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
yes something to think about
I think impulse and step responses are not the right measurements to look at in deciding which driver to delay. The second order gradient is bandwidth limited at higher frequencies, but the impuls response has a very wide spectrum.
What you want is wide-band cancellation to the back. The only way to achieve that is by putting the rear driver in anti-phase with the front driver and delaying it so that from the rear perspective the drivers are time-aligned. The upper frequency limit is determined by the distance between the drivers. When the distance is a half wavelength, you get cancellation at the main frontal axis.
If you want to do meaningful impulse and step response measurements, first set a low-pass filter so that you don't get the frontal null. Then you'll get an entirely different result.
i dont know man, listened rear polarity - up to 50cm delay and it didnt sound as good as front delay impulse matched
how does it differs to this?
Ground Sound
this has front one delayed.
Im gonna give just one chance to version which has absolute minimum to rear radiaton no matter what on front, if it sound crap this whole idea is going to be
An externally hosted image should be here but it was not working when we last tested it.
It's not entirely clear to me how the system on the groundsound page works.
Try these:
Basic theory
Subwoofer Directivity - OSA International, Inc.
Lessons learned in practice
http://www.diyaudio.com/forums/multi-way/14697-second-order-gradients.html
More theory
http://projekter.aau.dk/projekter/files/32248004/report.pdf
Try these:
Basic theory
Subwoofer Directivity - OSA International, Inc.
Lessons learned in practice
http://www.diyaudio.com/forums/multi-way/14697-second-order-gradients.html
More theory
http://projekter.aau.dk/projekter/files/32248004/report.pdf
One of my favorite design: Anyone needing support ? go to X-Fi
http://www.bd-design.nl/forum/images/uploaded/201207081526504ff98a9a3ae47.jpg
http://www.bd-design.nl/forum/images/uploaded/201207081526504ff98a9a3ae47.jpg
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TangBand & Gladen
Hi Orlando,
did you make these?
how wide is the gap?
does it extend the lows?
how far?
they look like: I want to build these too!
Hi Tyimo,
It is certainly not the same area. This is a quite smart and (IMHO) good looking way to enlarge the distance between the back and the front of the unit. Result is a better bass performance.
I have used the SLOB in various of my speaker attempts and it works very well.
Since this is a gallery some pics of my OB attempt using the same principle: the Poormans PAP 12 (inspired by the Pure Audio Project PAP 15)
It is certainly not the same area. This is a quite smart and (IMHO) good looking way to enlarge the distance between the back and the front of the unit. Result is a better bass performance.
I have used the SLOB in various of my speaker attempts and it works very well.
Since this is a gallery some pics of my OB attempt using the same principle: the Poormans PAP 12 (inspired by the Pure Audio Project PAP 15)
