Hi
I am a big Horn fan and lave a precise 3D Soundstage.
At the moment i habe EV HP6040, selfmade Midbass and selfmade dipol woofer.
A big part of my hobby ist the building... maybe more than hearing music, so i am looking for a now project.
My initial plan was to build the SyntripP, but Art suggest to modify my HP6040 could be the better way because of the better polar pattern.
https://www.diyaudio.com/community/...-single-point-source-horn.264485/post-7390431
Because i don't want to hi jack his thread (thx Art for all your help!) i am starting a new thread.
So i have the HP9040 and TAD-4002 driver. HP9040 is a 2" Horn and the TAD is 1.5" with an original adapter to 2". The adapter makes it, that i have around 11cm throught to diafrgma.
I want to xover at 500 Hz so Lambds/4 is ~17cm. That means i have to cut the holes ~6cm from the throat.
Attached some pic's from the driver and the horn. What do you think... could be succsessfull?
The planed drivers from ~100 to 500Hz are 4* 4NDF34
Thx a lot and greetings
Christian
I am a big Horn fan and lave a precise 3D Soundstage.
At the moment i habe EV HP6040, selfmade Midbass and selfmade dipol woofer.
A big part of my hobby ist the building... maybe more than hearing music, so i am looking for a now project.
My initial plan was to build the SyntripP, but Art suggest to modify my HP6040 could be the better way because of the better polar pattern.
https://www.diyaudio.com/community/...-single-point-source-horn.264485/post-7390431
Because i don't want to hi jack his thread (thx Art for all your help!) i am starting a new thread.
So i have the HP9040 and TAD-4002 driver. HP9040 is a 2" Horn and the TAD is 1.5" with an original adapter to 2". The adapter makes it, that i have around 11cm throught to diafrgma.
I want to xover at 500 Hz so Lambds/4 is ~17cm. That means i have to cut the holes ~6cm from the throat.
Attached some pic's from the driver and the horn. What do you think... could be succsessfull?
The planed drivers from ~100 to 500Hz are 4* 4NDF34
Thx a lot and greetings
Christian
Next question I have:
Due to the stabilization of the driver mount, it is a bit difficult to mount the drivers there. I know the < 1/4 wavelength rule is for the hole in the horn all the way to the driver and cannot be corrected by a delay.
But if I double the horn with some wood and make the openings longer... is that a problem? I have no idea how longer ports affect the system.
Maybe a little bit like this:
In the end I will time align everything via DSP to make sure the larger port is set correctly.
Thx
Christian
Due to the stabilization of the driver mount, it is a bit difficult to mount the drivers there. I know the < 1/4 wavelength rule is for the hole in the horn all the way to the driver and cannot be corrected by a delay.
But if I double the horn with some wood and make the openings longer... is that a problem? I have no idea how longer ports affect the system.
Maybe a little bit like this:
In the end I will time align everything via DSP to make sure the larger port is set correctly.
Thx
Christian
I'd try to keep the ports as short as possible. If I remember correctly, adding to port length acts as an acoustic low pass filter. You can use something like Hornresp or some other BEM application to check the effect of port length in your particular case, but it's probably easier to prepare two different mounting plates out of wood of different thicknesses and check the acoustic response directly.
Modeling isn't always accurate, but acoustically measuring prototypes always works. 😉
Chris
For a 500Hz crossover a longer port will actually be advantageous. Hornresponse or simply screwing a driver to a flat baffle and playing with some different port lengths will give a good idea. 500Hz is easy.
Hi
Thanks for coming into my thread to help!
It seems i need to learn hornresp 😉
But to get a more flexible testing chance, i have cut the throat of my horn in i will build new ones for testing 😉
I took all of my courage and zack 😉
I will keep you updated 😉
Thanks for coming into my thread to help!
It seems i need to learn hornresp 😉
But to get a more flexible testing chance, i have cut the throat of my horn in i will build new ones for testing 😉
I took all of my courage and zack 😉
I will keep you updated 😉
Eagerly watching what you are doing !
I bought a JBL 2384 and a ME464 horn, to see if I could fit cones onto them, but have never 'seen the light' on how I want to begin.
I'm hoping you'll shine some light 🙂
Wish I had more advice about small mid ports, but I've only used them on plain straight-walled conicals. When it comes to using ports that are longer than the horn wall, I'm clueless. My bet is @cowanaudio is best info around on them.
What I have found from playing with the 4ndf34, and other larger drivers on a flat 12mm baffle, just measuring what comes out of the port (which was a straight hole),
is that generally:
the larger the port, the lower the freq response extends
the more centered the port under the cone, the smoother the freq response
and the less volume between the cone and horn wall, the higher the freq response extends, but with a sharper the rolloff.
On small 4" mids. I've had good luck with holes that give a port area to Sd ratio around 1:12-14
On larger drivers I've found 8-12", I've found 1:8 works well
I do think of a "compression ratio" that way, reciprocally.
I see optimal port placement in the horn, as being about increasing efficiency via acoustic loading.
Even with optimal port placement for loading, I'll be surprised if you can get 4" mids to do really well below say 150Hz.
I'd echo Art's comments in his thread about trying to reach too low with them. ( I should add though, i really do like keeping drivers below xmax)
GOOD LUCK !
hope any of this helped
I bought a JBL 2384 and a ME464 horn, to see if I could fit cones onto them, but have never 'seen the light' on how I want to begin.
I'm hoping you'll shine some light 🙂
Wish I had more advice about small mid ports, but I've only used them on plain straight-walled conicals. When it comes to using ports that are longer than the horn wall, I'm clueless. My bet is @cowanaudio is best info around on them.
What I have found from playing with the 4ndf34, and other larger drivers on a flat 12mm baffle, just measuring what comes out of the port (which was a straight hole),
is that generally:
the larger the port, the lower the freq response extends
the more centered the port under the cone, the smoother the freq response
and the less volume between the cone and horn wall, the higher the freq response extends, but with a sharper the rolloff.
On small 4" mids. I've had good luck with holes that give a port area to Sd ratio around 1:12-14
On larger drivers I've found 8-12", I've found 1:8 works well
I do think of a "compression ratio" that way, reciprocally.
I see optimal port placement in the horn, as being about increasing efficiency via acoustic loading.
Even with optimal port placement for loading, I'll be surprised if you can get 4" mids to do really well below say 150Hz.
I'd echo Art's comments in his thread about trying to reach too low with them. ( I should add though, i really do like keeping drivers below xmax)
GOOD LUCK !
hope any of this helped
Yeah ! Really cool.
I'm loving the whole shop...what we can see of it !
Good luck! I’ve got a pair of JBL 2360 horns that I’ve been tempted to do this too, interested to see your results.
Thx for joining 😉
Every help and tip is welcome 😉
The TAD 4002 is a 1.5" Driver with 2" adapter, the HP6040 is original a 2" horn. But because of the adapter, there is not that much space for the mid-driver, because i have cut the throut. Now i will try to 3D CNC the new throuhgt... fingers cross, that this will work... normaly i do just 2D 😉
I will try to cnc it in two halfs and then glue them together.
That's one half:
Lets hope 😉
Christian
Every help and tip is welcome 😉
The TAD 4002 is a 1.5" Driver with 2" adapter, the HP6040 is original a 2" horn. But because of the adapter, there is not that much space for the mid-driver, because i have cut the throut. Now i will try to 3D CNC the new throuhgt... fingers cross, that this will work... normaly i do just 2D 😉
I will try to cnc it in two halfs and then glue them together.
That's one half:
Lets hope 😉
Christian
Just a little tip - use wooden dowels to align the halves, it is much more difficult without them.
Hi Pelanj
Yes, that’s exactly the plan 😉
Just a little busy at the moment ;(
Christian
Yes, that’s exactly the plan 😉
Just a little busy at the moment ;(
Christian
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If somebody is interested in the Sketchup/ STL File of the Throat 😉
It is still without MidBass drivers, to check, if Frequency response is close to the original. The model is without the little "wings" at the start of the throat.
Christian
It is still without MidBass drivers, to check, if Frequency response is close to the original. The model is without the little "wings" at the start of the throat.
Christian
this is some extreme horn modification! they way I think about the mids is that they are 4th order bandpass and so increasing the port length will lower the tuning frequency, it will also lower the frequency of the pipe modes of the port. For 500Hz probobly not so much an issue. To an extent this can be counteracted by reducing the volume of air under the cone (chamber volume) using a cone volume filler. However if your mid can reach 500Hz without such measures its better to not included them as the low pass filter formed by the 4th oder bandpass decreases out of band output reducing harmonic distortion Ideally for this frequency range I would use a larger mid but for home output levels 4*4" should be OK.
Hi Kipman
What do you mean by "extreme horn modification" it won't be modifyd so much! It will keep the original shape. I just modify it that way, that i don't need the 1.5" to 2" adapter for the TAD 4002.
Or do you mean "increasing port length"? This is not needed anymore 😉
Driver: here i am open minded... just choose the 4" because many others using them.
Here my first cnc test... it seems that my cnc can do 3d 😉
Christian
What do you mean by "extreme horn modification" it won't be modifyd so much! It will keep the original shape. I just modify it that way, that i don't need the 1.5" to 2" adapter for the TAD 4002.
Or do you mean "increasing port length"? This is not needed anymore 😉
Driver: here i am open minded... just choose the 4" because many others using them.
Here my first cnc test... it seems that my cnc can do 3d 😉
Christian
Puhh...
Theory behind the bandpass ist difficult to me... especialy, because in my horn the Driver is mounted very close to the throat... so the horn itself should start to load from ~300Hz.
It seems, this is something what just can be figured out with testing.
I am working wit AJ Horn... german version... sorry.
Attached 2 AJ Horn versions with Beyma 12"LX60V2, have 2 in my midbass Horns.
First normal Bandpass, second with a horn in front.
But what do you think about the Beyma driver??
https://www.beyma.com/en/products/c/low-mid-frequency/112LX60V28/altavoz-12lx60-v2-8-oh/
Theory behind the bandpass ist difficult to me... especialy, because in my horn the Driver is mounted very close to the throat... so the horn itself should start to load from ~300Hz.
It seems, this is something what just can be figured out with testing.
I am working wit AJ Horn... german version... sorry.
Attached 2 AJ Horn versions with Beyma 12"LX60V2, have 2 in my midbass Horns.
First normal Bandpass, second with a horn in front.
But what do you think about the Beyma driver??
https://www.beyma.com/en/products/c/low-mid-frequency/112LX60V28/altavoz-12lx60-v2-8-oh/
OK...
This is the first plan with 2 12". Will try it first with small openings, to make sure, that i still ha a good hornshape for the tweeter... can make them bigger later on 😉
Don't forget, that i just use them at home... so no high SPL, what will keep the amount of moved air small, and so hopefully no wind noise in the ports 😉
Why the 12": i am already using them exactly in the same frequency range! And: i already have two for testing here 😉
Have removed the second bass to show the openings.
What do you think?
This is the first plan with 2 12". Will try it first with small openings, to make sure, that i still ha a good hornshape for the tweeter... can make them bigger later on 😉
Don't forget, that i just use them at home... so no high SPL, what will keep the amount of moved air small, and so hopefully no wind noise in the ports 😉
Why the 12": i am already using them exactly in the same frequency range! And: i already have two for testing here 😉
Have removed the second bass to show the openings.
What do you think?
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The holes look too small (good size is 1/8 - 1/10 of Sd per woofer). And they seem to be too close to throat for 500 Hz crossover, but that can be just the scaling.