That's a little different. PA will be seeking direct coverage. The shape of the line and the levels of the parts will have to take into account the audience direction and distance. As to whether shading is a part of this, consider the size of these speakers. You wouldn't want to use a line where a 3D array is needed. These individual units are larger and have more directivity on their own.
Page 48 of the pdf..
https://www.linkwitzlab.com/LX521/Keele - Introduction to CBT Loudspeaker Arrays.pdf
https://www.linkwitzlab.com/LX521/Keele - Introduction to CBT Loudspeaker Arrays.pdf
I'd like to respectfully disagree.
When in the history of music before hifi did people sit motionless and alone in a chair and listen to music with their head in vise?
Aren't there still a lot of people who do like to get up and dance?
I host listening parties on a regular basis. I had one last week with a dozen people and it sounded great for everyone in the room. The picture below is the "Flanagangsters" which are Constant Directivity Dipoles. We had it at a hotel where a bunch of clients came to a seminar. We call it "bourbon night". Everyone picks a song and we all listen to music for a couple of hours.
Something regular people almost never do anymore - not without screens anyway.
Like my Open Baffle designs, the Shaded Arrays have the same quality of "every seat in the house is good" and I think that's a great priority for a speaker design.
Thanks for that presentation....somehow I've missed it until now.
Have you ever seen a real deployment of either of the examples shown on pg48, what you describe as a '3D array'?
I haven't.
Bass arrays are not uncommon. In a domestic situation, a bass array can help manage room modes. Generally speaking though it's no different than the mouth of a waveguide really, control of H and V with shading for diffraction control.
I can't begin to connect the idea of a 'bass array' to that of what you termed a '3D array' (per pg 48).
Can't even picture what a 'bass array' might look like, other than maybe like the various well known PA/install cardioid deployments.
.........Deployments that are all known not to work well in small room situations.
What do you mean by 'bass array'?
Can't even picture what a 'bass array' might look like, other than maybe like the various well known PA/install cardioid deployments.
.........Deployments that are all known not to work well in small room situations.
What do you mean by 'bass array'?
Ok, thx. DBA's I'm familiar with.
They seem like an entirely different animal than what's been being discussed. I tend to view them as active bass traps.
They seem like an entirely different animal than what's been being discussed. I tend to view them as active bass traps.
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Why? Arrays have width and depth. They define a wavefront shape. They can either have edges that taper using shading to act as a termination, or they can end at a wall and use it as a mirror. The DBA sections use an entire wall and create a plane wavefront that travels without expanding. It could be referred to as an infinite array.
In an abstract sense they're related: just in the sense that at bass frequencies the wavelengths are so long that below 100Hz (wavelength = 10 feet / 3 meters) you can have an array with woofers spaced 1-3 feet apart.
Thx Perry, I just edited my response before seeing your post....to say "I tend to view DBA's as active bass traps".
But readily admit, I haven't looked very deeply into DBA's.
But readily admit, I haven't looked very deeply into DBA's.
Rather than 3" drivers, would it make any sense to array up four slim drivers, each 3" by 12"? These are NOS alnico made by IREL and cover 90hz to 10k pretty well (with Italian warmth); possibly with a supertweeter (position and direction TBD). What would be the pros and cons? Is combing solvable? Advice appreciated!
Sorry these are probably vintage TV speakers, 4ohm but no other specs. I tone-swept one by ear over a leaky ~5L box. Four pieces Sd ~12" driver. Configured in a slim array, combing is likely a problem but I haven't tried it yet (convex, concave, shaded up or down...). Arranged alternately vertical and horizontal the ctc would be only 6" but not as striking; staggered slanted even closer.
Interesting challenge no?
Interesting challenge no?
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These are interesting drivers, but I would never use them in a shaded array. It would create all kinds of combing and directionality problems in the treble.
Perry Hi
I am relatively new in DIY audio hobby and seen a lot of people make share / sell designs I must say you are my top favourite. I am about to make OB using some of your plans that you shared. I also have miniDSP and like that miniDSP is always part of your plans. I dont have skills of making soldering crossover
I currently have a LXmini ( its good for a start ) but I need to go higher level more pressure
Thank you for sharing your plans and that too FREE. God bless you. I believe God gives one more Knowlege when one shares
Do you have any plans in future based on Omnidirectional speaker , FAST ( FullRange assisted Subwoofer speaker) a great soundbar and something like a Dut& Dutch 8c cardiod.
thank you again Perry.
regards
anand
I am relatively new in DIY audio hobby and seen a lot of people make share / sell designs I must say you are my top favourite. I am about to make OB using some of your plans that you shared. I also have miniDSP and like that miniDSP is always part of your plans. I dont have skills of making soldering crossover
I currently have a LXmini ( its good for a start ) but I need to go higher level more pressure
Thank you for sharing your plans and that too FREE. God bless you. I believe God gives one more Knowlege when one shares
Do you have any plans in future based on Omnidirectional speaker , FAST ( FullRange assisted Subwoofer speaker) a great soundbar and something like a Dut& Dutch 8c cardiod.
thank you again Perry.
regards
anand
Anand,
No plans for any of the above, unfortunately, though I do think the Birch Dipoles could be converted to a cardioid with a 2nd woofer and a box. I’m delighted that you find my designs helpful!
No plans for any of the above, unfortunately, though I do think the Birch Dipoles could be converted to a cardioid with a 2nd woofer and a box. I’m delighted that you find my designs helpful!