New DIY Mid High (90deg) - AKA PM90

I start by first thanking all for so much giving with regards to the evolution of this project,
I was wondering if this Horn. http://www.usspeaker.com/paudio ph-3223-1.htm. would lift the cd far enough from the 12” chassis to allow the use of a 2” cd instead of the 1.4” for cost saving as i can get them far cheaper.
And would the 2” also be comparable to the 1.4 (acoustically)
Would it affect the spl of the high-mid/high?
 
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Yes I beleieve it will fit. The RCF will have better pattern control and has a lower cut off frequency; 400Hz Vs 500Hz.

The mid section must not be crossed over any higher than 700 - 800Hz ... I suspect you may get away with 700Hz with this horn.
 
Peter Morris said:
Yes I beleieve it will fit. The RCF will have better pattern control and has a lower cut off frequency; 400Hz Vs 500Hz.

The mid section must not be crossed over any higher than 700 - 800Hz ... I suspect you may get away with 700Hz with this horn.
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I thank you greatly for your rapid reply, sharing & time. I fully intend to make a pair of these in the coming months i have been looking for a compact enough tapped horn for a powerful flat to 40 sub. I would also love to design a slightly/deeper larger top cab version around the 1.4” driver on rcf horn with 4 12”, based on your concept of max spl small package to sit on top of 4/6 bass/sub cabs. I have been looking at mounting the 4x12’s in 2 banks of 2 on manifolds something like this

But with a more acute manifold angle for this pm style 4x12” 100 hz up top of bass cab box.
If they could be squeezed into a box do you think the manifold into pm concept would work (acoustically)?

Would the bms1.4” cd hf keep up with 4x12”s?

Would the cd vhf also keep up?
 
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Max said it all more or less as I would have. A few notes:
  1. Our design is unique, has its own patent for the midrange phase plug that allows the two drivers to work in concert, and would not be covered by any of BMS’s patents regardless. History has forgotten the other ring radiator drivers, which pre-date either design, but it is easy to suggest similarities when there are only two products of this type in the world.
  2. There are a few of these in the field now, with our largest OEM customers, and their testing bears out our own. If you don’t see an advantage on paper I suggest that says a lot about the validity of calculated maximum SPL :)
  3. We expect better distortion in general due to a different diaphragm material, general diaphragm shape optimizations due to our FEA expertise, and not chasing very high sensitivity with high compression ratios. Thats especially true at the bottom range of the MF diaphragm. No bottoming problems here.
  4. Marketing is pretty hard for a company that sells primarily to OEM customers all fighting each other for market dominance. Let’s just say we’re bad at it and prefer to talk in person. Much easier to keep everyone’s business and design directions separate that way.
 
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I just pulled the trigger on 2 of those bms coaxials, horns & twelves will have to wait?
Peter sir i’ll be Biulding as per your concept thank you all who helped this along.
Which file should i use for cnc cutting please, also if the twelves were flat out what would you estimate the coaxials have in reserve?eg 50%-30%etc.
Also Should i post progress pics?
 
Which runs out first - it depends on where you crossover to the subs and of course the music type - As a guess if you cross above about 140Hz the horns will struggle, its its more like 100Hz or less then its the 12's
 
Peter Morris said:
Which runs out first - it depends on where you crossover to the subs and of course the music type - As a guess if you cross above about 140Hz the horns will struggle, its its more like 100Hz or less then its the 12's
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Thank you once again.
So would I be correct in guessing I could do a small gig for say 200-300 with these down to 80-100 and 2x double 18's subs for low end extension. also I could go with 2 of the 60/40's a side from 100hz up & 2 way bass-low bass for larger venues of 1000 plus?

I am in the process of getting CNC quotes in the UK if that works out I'd be happy to pass on the details here if that is ok to do on this site/thread.
Kind of new here.
Oh & a lot of D&B tracks hit 25hz or so, then it gets played with a Response curve this shape
208921
on that note I must admit under my bed lays a big sub and these will spend there spare time keeping it's company?.
 
I would recommend 1 x PM90 + 1 x good double 18’ sub per side crossed at 100Hz.

With most types of music the 18's will run out first. If its EDM, use 2 x double 18” crossed at 110Hz to 1 x PM90.

For larger shows used 2 x PM60 crossed at 100Hz with 2 x double 18” subs per side, if you want a bit more 3 x double 18” sub crossed at 110Hz.

…. so yes I think you could do 200-300 people with 1 x PM90 per side and may be up to 800 - 1000 people with 2 x PM60’s a side, but it really does depend on what your expectations are.
 
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