Going to try and keep this simple, because I think I know the answer,
But my thoughts
Coxial driver 13.5 BC cxn88
Sealed
Just for fun 400hz hp to LF driver
And the mid 2k
In a 1cuft box and 1000w
There's 1mm of movement on the cone
80* coverage is better then all normal size horns ,
But when I put this speaker horizontal
Won't the LF driver hinder that 80* ???
Is there any difference if the BC dcx464 ccd is used on the 18Sound xt1464 horn ?
But my thoughts
Coxial driver 13.5 BC cxn88
Sealed
Just for fun 400hz hp to LF driver
And the mid 2k
In a 1cuft box and 1000w
There's 1mm of movement on the cone
80* coverage is better then all normal size horns ,
But when I put this speaker horizontal
Won't the LF driver hinder that 80* ???
Is there any difference if the BC dcx464 ccd is used on the 18Sound xt1464 horn ?
Hi,
Not sure i totally get what you want to do so, i assume you want to do an MTM with a coax as T:
Lower xover point to coaxial woofer if you want to use mtm horizontally, otherwise you'll run into issues about directivity ( narrowing) with mtm.
If you can lower an octave you should be fine ( circa 200hz or lower).
If needed use a Linkwitz transform to go lower.
Can't tell about dcx464/horn comparison.
Not sure i totally get what you want to do so, i assume you want to do an MTM with a coax as T:
Lower xover point to coaxial woofer if you want to use mtm horizontally, otherwise you'll run into issues about directivity ( narrowing) with mtm.
If you can lower an octave you should be fine ( circa 200hz or lower).
If needed use a Linkwitz transform to go lower.
Can't tell about dcx464/horn comparison.
Correct in your answer, I am considering the mtm design horizontal,
200hz might be very difficult in a passive crossover,
400 hz I can see,
What is a Linkwitz transform ?
If my baseline is 80*
is there a way to know how narrow it will.get ?
200hz might be very difficult in a passive crossover,
400 hz I can see,
What is a Linkwitz transform ?
If my baseline is 80*
is there a way to know how narrow it will.get ?
An LT is a special kind of eq used to change QTC of box+driver to match an arbitrary choosen FS and Q. Iow it offer a way to adapt any driver to any desired response once in a sealed box.
That said there is limitation to principle ( first ones being driver xmax and amp power needed- 12db/octave usually, with your 1kw amp you can expect average 125w for a full octave gained but it'll depend... it's easily simulated). With dsp widespread it's no very easy to implement but you can do it in analog too. Worth a read:
https://sound-au.com/linkwitz-transform.htm
There is other possible answer to achieve lower fc without an LT but this is ime the most flexible answer
Any loudspeaker simulation program can give you an idea of directivity narrowing you could face ( Virtuix cad2 comes to mind).
Can you elaborate your plan, your description is too short ( use you plan - PA, Home Cinema,..., drivers you will use as M in your MTM, the kind of load they will see(BR, Sealed, whatever..., max peak SPL you need at sweetspot, distance of said sweetspot,... ).
That said there is limitation to principle ( first ones being driver xmax and amp power needed- 12db/octave usually, with your 1kw amp you can expect average 125w for a full octave gained but it'll depend... it's easily simulated). With dsp widespread it's no very easy to implement but you can do it in analog too. Worth a read:
https://sound-au.com/linkwitz-transform.htm
There is other possible answer to achieve lower fc without an LT but this is ime the most flexible answer
Any loudspeaker simulation program can give you an idea of directivity narrowing you could face ( Virtuix cad2 comes to mind).
Can you elaborate your plan, your description is too short ( use you plan - PA, Home Cinema,..., drivers you will use as M in your MTM, the kind of load they will see(BR, Sealed, whatever..., max peak SPL you need at sweetspot, distance of said sweetspot,... ).
Nothing is set in stone yet,
These are just ideas and open to advice,
Not trying for a full range speaker
F3 of 58hz
F6 of 42hz
Should be nice for home theater and music as well with the natural roll off
LF driver BC 15BG100 X 2
Mtm
4cuft box sealed
500hz crossover point should be very easy ( fingers crossed)
I understand lower is better
BUT
In a passive crossover 400ish might be it
The BC 13.5 CXN88 Coxial driver in a 1cuft box sealed,
These ate my thoughts at this time,
These are just ideas and open to advice,
Not trying for a full range speaker
F3 of 58hz
F6 of 42hz
Should be nice for home theater and music as well with the natural roll off
LF driver BC 15BG100 X 2
Mtm
4cuft box sealed
500hz crossover point should be very easy ( fingers crossed)
I understand lower is better
BUT
In a passive crossover 400ish might be it
The BC 13.5 CXN88 Coxial driver in a 1cuft box sealed,
These ate my thoughts at this time,
Working out the answer to your question is a complex task. While it could be done, you may find yourself building and then coming back to your question after you have measurements.
I'm not sure you need such a large compression driver but that's your choice. If I were looking for a project using that horn I'd probably choose to cross it above 3kHz, but others have crossed it lower.
I'm not sure you need such a large compression driver but that's your choice. If I were looking for a project using that horn I'd probably choose to cross it above 3kHz, but others have crossed it lower.
Yes. in the Horn the coax CD finds a much better enviroment and the dispersion is usually much more uniform, the FR doesn't change that lively over the angles. Most cone coax drivers have a more linear FR at an angle (often ~15°) than on axis.
Here an example FR of a 10" coax with the horn within the VC of the mid-bass.
at ~15° off axis it's the most neutral (if you can call it that anyway) but not very satisfying under other angles, so not a good choice for a center or if you want to change the listening position. And yes, that's already with the crossover.
These are measurements form a German forum with differen horn drivers on different horns. You wioll also find the DCX on a XT1464:
https://www.lautsprecherforum.eu/viewtopic.php?t=8073
The guy who did this made a remarkable measuring marathon !
Regards
Charles
https://www.lautsprecherforum.eu/viewtopic.php?t=8073
The guy who did this made a remarkable measuring marathon !
Regards
Charles
Hi, my 2c on a MTM using the 14cxn88, with a couple of 15"s around it.
I'd plan on keeping the vertical stack as tight as possible, hoping to keep the 15"s within 1/4 WL....which means a 100-110Hz crossover to the coax cone.
Which also means making that crossover active.
I might use B&C's passive xover for the coax to save amp channel count, but no way would i go passive for the 15"s to coax.
Then, I think you can choose 15"s that are optimized more for sub duty than trying to reach up to a 3-400Hz xover....which is an unacceptable compromise, imo.
I say all this from using the 15cxn88 on an 18", and in between two 18"s.
Can also say, the dcx464 with XT1464 is a cleaner sound no doubt. The 15cxn88 is very pleasant, but it's not in the same league as the CD/horn combo.
I use 12"s with the dcx464 and XT1464, either MTM or both under the coax. The 12"s reach down to sub, again at 100Hz or so.
Good luck !
I'd plan on keeping the vertical stack as tight as possible, hoping to keep the 15"s within 1/4 WL....which means a 100-110Hz crossover to the coax cone.
Which also means making that crossover active.
I might use B&C's passive xover for the coax to save amp channel count, but no way would i go passive for the 15"s to coax.
Then, I think you can choose 15"s that are optimized more for sub duty than trying to reach up to a 3-400Hz xover....which is an unacceptable compromise, imo.
I say all this from using the 15cxn88 on an 18", and in between two 18"s.
Can also say, the dcx464 with XT1464 is a cleaner sound no doubt. The 15cxn88 is very pleasant, but it's not in the same league as the CD/horn combo.
I use 12"s with the dcx464 and XT1464, either MTM or both under the coax. The 12"s reach down to sub, again at 100Hz or so.
Good luck !
Nice you've posted the link. I have to mention the directivity measurements do not match the upper half to the lower one, the horns aren't asymmetrical but the lower half is normalized, the upper part is not.
He indeed did! Thanks again for posting the link.
Dude!.......a dual 15 MTM for "home theater" use?.............who are you trying to kill? LOl
Don't judge him! He just wants to watch his new 250" TV at home from his summer house! 😀
Now now easy guy lol,
I have allways wanted to build 3way
The dcx464 has been on my list from day 1
The mtm 15s would make a very fun 2 channel setup
I have allways wanted to build 3way
The dcx464 has been on my list from day 1
The mtm 15s would make a very fun 2 channel setup
12ft
120db is easy
200w
The bc 15bg100 are about 93db combined
Yes I understand full over kill,
At 12ft/4m? That must be at least 6dB more, you've got 2 main speakers, don't you?