Learning to design speakers

Oh and hum away if you must

May idea for an unusual phase plug involves an adaptation of the horn within a horn design. I also got this from have been involved with dirt track racing oddly enough.
Since I am sure that sounds pretty crazy, I will elaborate
In dirt track racing their is no windshield. That is replaced with expanded metal (which has diamond shaped openings. This lets in light waves so yo can see, but not large dangerous fly objects!

In a horn one of the functions of the phase plug is to pull some of the upper frequency range waves back to the center so it doesn't create a hole in the coverage.
You could in theory put a say a6.5 inch driver in that phase plug. The horn for that driver in its frequency range shouldn't need to be too long to fill in a hole in the mid highs. That creates another problem though. you need to disperse the waves in its range and still need to bring waves back to the center as mentioned earlier.
A possible solution would be to make frame in the shape of the desired phase plug, curving in front of the 6.5 driver and use a sheer fabric that easily allowed larger waves to cling to the outside but allowed dispersed small waves to be dispersed and pass through.
It probably does sound quite crazy...it is likely to take tremendous R&D, but I am reasonably sure it could be done
Oddly enough, I think Pantyhose may be a likely candidate !!!! It may require slightly larger holes in the fabric, but that is what I would try first!
I hope I described it well enough. It may be difficult to visualize exactly what I am proposing! My biggest problem is with my back I can't really build it right now and I am not good at communicating most of my ideas! I have seen failed efforts at this idea using cellular foam...that blocked out to much!

I think I understand, so you are proposing that I cover my phase plug in a thin cloth in order to attract high frequency waves? I have no idea why or how that would work,also are you trying to say I should put a 6.5 inside my phase plug? I'm confused... It sounds like a cool theory and I'm open to any ideas atm! I will definietely read up some stuff but if it works I'll let you know, ill even post pics on here of the plug and response. I'll reread the post when I'm more awake and maybe i can make more sense of it, thanks bjm

dnb123 wrote: I think I understand, so you are proposing that I cover my phase plug in a thin cloth in order to attract high frequency waves? I have no idea why or how that would work,also are you trying to say I should put a 6.5 inside my phase plug? I'm confused... It sounds like a cool theory and I'm open to any ideas atm! I will definietely read up some stuff but if it works I'll let you know, ill even post pics on here of the plug and response. I'll reread the post when I'm more awake and maybe i can make more sense of it, thanks bjm

I was afraid my description would be inadequate, and it is. My fault. The idea has a high level of practicality.....once developed! This would likely require a high level of research and development first. High enough I can't really ask anyone to try it.
What I appear to have definitely been correct about however is that you are interested enough to think about the concept. Maybe I can describe it well enough you can understand it better!
Maybe if I describe it well enough, you might get inspired enough to try some variation of it that made sense to you as well. You are saying you intend to build some cabs with replaceable phase plugs..that does seem like a good situation to try this! However the possibility that it would delay you is high, so if you do not want to try it, I thoroughly understand.
I am not suggesting putting material on a completed phase plug. I am suggesting building a phase plug that approximately the last 2/3 of it on the outward phase plug is a wire framework, with sheer enough material to allow smaller waves to pass through, though they should be slightly diffused. That is a desirable side effect anyway! slightly!
Slightly behind that framework would rest a smaller driver for the next range up of sound reproduction.
The holes in the material being that small would in theory present a surface that the upper portion of the frequency range from the driver behind it would still be directed back to the center.
I am not trying to fool you though. There has been no development to my knowledge and it is only a theory. As I mentioned before, the closest thing to it I have seen was a cellular foam diffuser that didn't work as it was too restrictive.
Anyway, for now under your current circumstances it isn't worth the hassle to try and develop. I just thought you might enjoy thinking it through and considering the possibilities! Maybe some day you will be the person that does successfully develop that idea! I will probably be long gone when that day comes, if it comes! Who knows you might even mention my user name from here!
You will notice that while there are a lot of intelligent, highly skilled speaker designers around here,no one jumped up to volunteer to develop that. I am sure a good portion of those that see this will recognize 3 things, one that it is likely to be possible, two that it would be beneficial and three that it could potentially be far to resource consuming to develop!
Good luck with your real phase plug development, and thank you for indulging an old man in allowing me an opportunity to express this idea! Let us both cross our fingers a bit that maybe someday you or someone like you does develop this idea! Best to you! Bobby Mosley AKA BJM362

P.S. Hum hum Hum hum HUM!

Thanks Bobby that makes a lot more sense now, however the way I see it... I'm 17, I built this sound system essentially as a test and a way of learning for a (hopefully) future career in sound engineering. I like a challenge hence why me and my friends built this rig, also hence why I started designing. As Roger said before I am running before I can walk but the thing is running is fun I still read the important stuff but I said before, I'm all ears!
Your idea seems very unique and I would love to develop a new idea for myself (although the idea is yours) and thinking about it I was gunna make removable phase plugs in order to test different ones so it will do no harm to try your idea. I have a umik I can test materials with and I will start experimenting with this shortly. if it fail? I'll try again. Still fails? I don't really care, I've learnt a lot and I can always just try a line array hi mid horn again thanks for your contribution, it will be remembered!

also... DOES ANYONE HAVE THE LINK TO AKABAT? if not how can i find it?

oh... dw

i wrote this some time ago, worth a read....

www.freespeakerplans.com/kunena/8-advanc...-akabak-for-beginers

www.randteam.de/AkAbak/Index.html

Thanks man, I started reading the one you wrote a few days ago but I'm quite busy with college work, I'll keep this post updated as I start developing, feel free to drop ideas or ways in which I could do things. Also quick question... Would a phase plug be classed as a wave guide or as part of the throat/horn