EDIT: i just finalized my “end game array” system design, which means this horn system is no longer “end game” but simply “maximum performance”
i will detail the array design in a few days hopefully … but it will cost significantly more to build than this setup, perhaps about 30% more or so, or about $10,000 more. these are just rough estimates for now.
after reading what i wrote below i realized some of the references are out of order in that i refer to other things i wrote that were only mentioned AFTER the point where they are referenced … this is because i didn’t write everything in order but came back and added more information … do not be alarmed by this. i will not attempt to fix this because i will only keep adding more information in the future and things will only get worse anyway just keep reading it will all make sense in the end.
2.5 khz - 8 khz: JBL D2 ( D2430 ) on JBL Waveguide with 1.5" throat
as you notice both driver and waveguide are from speakerexchange / reconingspeakers because they are both replacement parts for JBL speakers rather than something officially sold retail like all the other drivers used in this system …
here is D2430 frequency response on a slightly different waveguide from JBL M2:
as you can see D2430 can be run all the way to 20 khz if desired, but it’s a 1.4" throat horn so it will beam in the very high frequencies and instead by using four supertweeters angled in different directions i can spread VHF energy more evenly rather than focusing it as a laser beam.
also Beyma supertweeter peaks in efficiency at 10 khz whereas D2 is already down by more than 5db @ 10 khz and more than 10db by 20 khz. Beyma Supertweeters are affordable and have widely available replacement diaphragms ( i had to replace one on my car audio version ) so rather than EQing the D2 up by over 10db in the top end i would rather cross it over to some supertweeters at around 8 khz.
i am trying to keep this XO point closer to 10 khz because that’s where the dip in Equal Loudness curves is:
otherwise if going by driver specs alone 6 khz would be the better XO point but it is too critical a frequency range and it’s better to move it to 8 khz to avoid the XO being audible …
i actually used a car audio version of this supertweeter crossed at 7 khz. they’re a bit harsh but they do give your system “air” and that’s what you want from a supertweeter. they make everything sound electric.
but whereas the element you see above has dual 15" woofers, four 8" mids and three HF drivers our array element uses two 15" woofers ( blue ) and three 8" mids ( magenta ):
and instead of 10-20 boxes like a prosound array there are only two boxes, so total of 4 x 15" woofers and 6 X 8" midbass.
woofer:
80 hz - 220 hz: 4 X 15" JBL 2265 HPL
midbass:
220 hz - 800 hz: 6 X 8" Beyma 8MC500Nd
i have used a 8" Beyma Midbass in the same car audio system as the Beyma Supertweeter and it was great. This is a more more modern and high end version of the midbass i used with additional technology such as inside/outside voice coil for example, but otherwise similar.
the main difference is really that there will be six of them per channel and four of the supertweeters per channel, which is appropriate because we’re covering a living room and not a mid-size sedan.
in the car i had the 8" beyma run to 125 hz which was supposed to cross over to the subs ( the car died before the subs were installed ) but in this application they will only be asked to work to 220 hz.
220 hz is also where JBL crosses their 8" to the 15" although of course their 8" is closed back and has an FS of 250 hz and can’t be crossed lower whereas i can cross lower but don’t need to.
the horn design has double the output but is 5 times the size. Eighteen Sound driver chosen for its refinement while Eminence for its sheer brute force.
again, the subs aren’t shown here because you can use any subs with this system anyway.
the purpose of this system is to create the highest performance possible system where at least some of the frequency bands are covered by a single driver.
in case of this system we are covering two frequency bands by a single driver each, and both of these drivers are dual diaphragm which means they are both the highest output drivers on earth for their particular frequency band.
BMS specifically claims their 4599HE is the loudest driver in the world while JBL doesn’t claim the same of D2 but i think it that for the frequency range in which i am using it in this design that is the case.
this all but guarantees the system has highest price / performance as well as complexity / performance ratio achievable.
the Beyma CP12/N has a much better directivity plot than JBL Selenium ST400 and the diamond pattern of 4 drivers is better than the 2 driver pattern on MD1.
and more generally my setup is intended to embarass the JBL Marquis Dance Club System:
my setup is inteded to have more output at almost every frequency ( versus full Marquis system ) while being compact enough to fit into the average living room.
the Marquis was discontinued and rightfully so. today in its place you would use something like the new SRX900:
but where Marquis failed as a Dance Club system it actually shows us the way to the ultimate home system …
my design has some of the similar vision that JBL misplaced by trying to turn Marquis into a dance club system ( where it should have been a high end home system ) except more modern …
a lot of the tech in the Marquis is archaic by modern standards, but it still inspires me.
actually make it 6 supertweeters. the actual pattern in this case is too complicated to explain but it doesn’t matter. you just aim them how you want to get desired coverage. you can also place them anywhere you want. for example i think it will be better to put them on the sides of D2 horn rather than in the middle of midbass array because then they don’t have to face up so dust won’t settle into the compression chamber where it may clog the driver.
with 6 supertweeters the total dimensions of 6 X 1" VC match that of D2 which has 2 X 3" VC … this would be consistent with Marquis system that had 2 X 1.5" VC supertweeters working with 1 X 3" HF driver.
just keep reading it will all make sense in the end.
