Double 10 and Horn

Peter Morris

Senior
May 8, 2011
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Australia
Hi Grant,

I don’t know the answer to this … but with d&B Q1 design, which is very similar to this, I have always been concerned about the different time arrival form the front and back of the speaker cone and reflections within that horn cavity as the frequency increases.

Mike crosses his over at 585Hz … may be to avoid that second big dip at about 730Hz

Also EAW KF364 is similar and they cross it at about 490Hz. Have a look at frequency response below. It looks similar but the two dips are at a higher frequency.
 

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Grant Manson

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ahh good spy on the specs, I some how missed that! Your totally right, it looks like the EAW but at a lower frequncy.

Edit: I'll have a go at adding some inserts into the horn mouth to see if that helps. Thanks for the suggestion
 
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Grant Manson

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Ok so it's defiantly to do with the horn cavity! Good thinking peter.

As a very rough experiment I tried placing two heavy books into the spare space in the cavity which completely remove the dip at 750hz.

We've found the culprit! It seems the gap i've left to squeeze the driver in is the perfect distance to cause reflections at the crossover point!

(Green = No book Red = With book)
test2.jpg
P.S this is a super rough measurment taken indoors.
 

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Chris Burns

Freshman
Nov 13, 2016
64
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8
Connecticut
Hello gang. It’s been a while for sure. Hope everyone is well during these crazy times.
Looking to finally rekindle my double 10/12 project from years past....

Is the best driver solution the 10MBX64 and the HF950 / ND950 combo (or B&C1090) with the 650hz X? I’ll be crossing at appx 110hz to Subs. Any new 10” drivers with better capability come along since? It seems there is less of a need for the BMS Coax with some of the newer drivers since my last go with this.

For a standard vented cab, is it still the case that moving up to a 12 adds to the distance and wavelength to the Horn and this kind of kills the matching geometry? If I recall the output capability of the 12 selection was much better at the time than the 10s. The Eminence KappaLite 3012HO and the 12ndl88 are very promising 12s.

curious with a 650hz cross on the 950 combo, if running it up to continuous program rated power brings distortion at the lower crossover? I assume a 24db/oct is being used in this case to protect the driver?

Thanks gang. looking to get going on this in the coming weeks.

If anyone has a completed build either MTM or MMT It would be great to see and hear about it.
 

Grant Manson

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Having built the MTM Version of the double 10 i would probably recommend the MMT version until a more finalised MTM version is available. It's an easier build and you won't have to deal with the issues of the horn cavity creating reflections. Obviously it will be a taller speaker but most of the time you want that tweeter nice and high!

As for 10 vs 12, you will want to stick with the 10" drivers for this type of design as the spacing is perfect for a 650Hz crossover. If you want to use 12's then I would recommend Pete's PM60/90 with the HF950/ND950 combo if you're trying to reduce costs. Harder design to build but higher output.

As for the 950 combo, I've been running it with a 24db/oct crossover. It's sounding great! As has been mentioned before, the ND950 is used in several of RCF's own speakers crossing at 650hz so I am more than confident that the tweeter is happy at that crossover.

Not had the chance to let my build fully rip yet but theoretically I should be looking at 132+ dB from my MTM mid tops.
 

Chris Burns

Freshman
Nov 13, 2016
64
3
8
Connecticut
Having built the MTM Version of the double 10 i would probably recommend the MMT version until a more finalised MTM version is available. It's an easier build and you won't have to deal with the issues of the horn cavity creating reflections. Obviously it will be a taller speaker but most of the time you want that tweeter nice and high!

As for 10 vs 12, you will want to stick with the 10" drivers for this type of design as the spacing is perfect for a 650Hz crossover. If you want to use 12's then I would recommend Pete's PM60/90 with the HF950/ND950 combo if you're trying to reduce costs. Harder design to build but higher output.

As for the 950 combo, I've been running it with a 24db/oct crossover. It's sounding great! As has been mentioned before, the ND950 is used in several of RCF's own speakers crossing at 650hz so I am more than confident that the tweeter is happy at that crossover.

Not had the chance to let my build fully rip yet but theoretically I should be looking at 132+ dB from my MTM mid tops.

Thanks Grant for all that feedback. I’m looking at the MMT 10 standard build with the 10mbx64s. If anyone has found a better more capable 10 from 100hz up please let me know. Ive looked at the Faital and 18S however the prices on those are in the mid 300$ range. What 10 did you use Grant?

Can someone give me a vendor to purchase the ND950 and HF950from? I did a search and can find nobody here in the US that sells them. Im sure with the worldwide pandemic thats not going to make it any easier for me. As a backup Im looking at the B&C 990 or, the new Eminence 314X!! She is spec’d to run down to 800hz with a 12db cross, Im confident she will run at 650 just fine with 18 or 24. Ive read great reviews on this new polymer design and the specs look amazing!! Im going to pick one up from PE and see how it looks on the horn.

Lastly, I have 5 18S XC1464 aluminum horns (10in x 10in) here. Im going to put the driver on it snd run some sweeps to see how it performs but, I know real world directivity needs close to a 24” wide format horn to keep a 60deg pattern down to 500hz, but if it begins to go lose control snd go omni around 800 or so that may be ok, there are OEMs that run this horn in the 60deg format. My ultimate goal is 2/side splayed for 120deg coverage. Thanks gang!!
 

Peter Morris

Senior
May 8, 2011
1,061
146
63
Australia
Hi Chris ,

FWIW I am currently working on a new design for the double 10 ... it looks like it will be the same size but with 2 x 12" drivers and a new horn design from Ciare. It will be a simple MTM design with every trick I can think of to improve how it arrays, the phase response and the LF pattern control in the lightest smallest box available.

I have parts on order but with Covid-19 things are moving very slowly.

https://usspeaker.com/ciare pr614-1.htm
https://www.comsol.com/paper/download/290171/cinanni_paper.pdf
https://www.bcspeakers.com/en/products/coaxials-hf/1-4/8/DCX464-8
 

Chris Burns

Freshman
Nov 13, 2016
64
3
8
Connecticut
Hi Chris ,

FWIW I am currently working on a new design for the double 10 ... it looks like it will be the same size but with 2 x 12" drivers and a new horn design from Ciare. It will be a simple MTM design with every trick I can think of to improve how it arrays, the phase response and the LF pattern control in the lightest smallest box available.

I have parts on order but with Covid-19 things are moving very slowly.

https://usspeaker.com/ciare pr614-1.htm
https://www.comsol.com/paper/download/290171/cinanni_paper.pdf
https://www.bcspeakers.com/en/products/coaxials-hf/1-4/8/DCX464-8
Peter I am going to wait patiently then!!!! Staying tuned. I assume this is a flat baffle vented design? Thats honestly all Im looking for.

Keep me posted and if I can help in any way please let me know.

I really like the Eminence KappaLite 3012HO for a 80hz F3 or higher for a 90-120Hz crossed design. The price is right and its really a fabulous driver. Then again the B&C 12NDL88 is a rock star with endless output.

I may repurpose my 4594s (non He) for this build.

Thanks Peter.

Peter while I have you, I have a quick novice question...

If I have a CD that has effective response on a horn from 500-18000, (flat 500-3500) however the manf says cross at or above 1k, due to the resonance FS at 950. The impedence spike is 850-950 and very steep (from 8-20 ohms). I really want this driver to suit my needs from 500-3000 as a mid in a three way, so with a 24db slope on the HP and a little limiting, and perhaps a bit of an active notch attenuation from 850-950hz, could I pull this off, or just deep 6 the driver (I really dont want to).

Thanks!!!!
 
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Grant Manson

New member
Nov 8, 2019
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Thanks Grant for all that feedback. I’m looking at the MMT 10 standard build with the 10mbx64s. If anyone has found a better more capable 10 from 100hz up please let me know. Ive looked at the Faital and 18S however the prices on those are in the mid 300$ range. What 10 did you use Grant?

Can someone give me a vendor to purchase the ND950 and HF950from? I did a search and can find nobody here in the US that sells them. Im sure with the worldwide pandemic thats not going to make it any easier for me. As a backup Im looking at the B&C 990 or, the new Eminence 314X!! She is spec’d to run down to 800hz with a 12db cross, Im confident she will run at 650 just fine with 18 or 24. Ive read great reviews on this new polymer design and the specs look amazing!! Im going to pick one up from PE and see how it looks on the horn.

Lastly, I have 5 18S XC1464 aluminum horns (10in x 10in) here. Im going to put the driver on it snd run some sweeps to see how it performs but, I know real world directivity needs close to a 24” wide format horn to keep a 60deg pattern down to 500hz, but if it begins to go lose control snd go omni around 800 or so that may be ok, there are OEMs that run this horn in the 60deg format. My ultimate goal is 2/side splayed for 120deg coverage. Thanks gang!!

I went with the Faital Pro 10FH520 as I wanted the option of running these without any subs for smaller gigs. They play great down to 60hz and have plenty of xmax & power handling to coupe with that.

As for retailers, I'm based in the UK so I wouldn't be able to help you on that front. Having thomann.de and bluearon.co.uk here is a god send!


Hi Chris ,

FWIW I am currently working on a new design for the double 10 ... it looks like it will be the same size but with 2 x 12" drivers and a new horn design from Ciare. It will be a simple MTM design with every trick I can think of to improve how it arrays, the phase response and the LF pattern control in the lightest smallest box available.

I have parts on order but with Covid-19 things are moving very slowly.

https://usspeaker.com/ciare pr614-1.htm
https://www.comsol.com/paper/download/290171/cinanni_paper.pdf
https://www.bcspeakers.com/en/products/coaxials-hf/1-4/8/DCX464-8

Can't wait to see what you come up with, this sounds very exciting!!
 

Peter Morris

Senior
May 8, 2011
1,061
146
63
Australia
Hi Grant, Chris & others,

One of the things I have tried to with my projects was to find solutions that are not generally provided by manufactures – The PM90 was designed to provide maximum SPL and quality on a pole mount speaker above 100Hz, The double 15” + Horn drum fill was to provide a double 15 that did not suffer from the typical comb filtering found with this combination, and the Double 10 was designed to be small, light and extremely powerful without compromise. I think RCF has now addressed this design with their new TT4.

The idea of this design is to do something different again, a box with two different angels – 25 degrees and 15 degrees. I don’t think any one has an angle as tight as 25 degrees … (?)

The reason to have two different angles is to get enough volume for the LF drivers. If you have two steep angles of 25 degrees or more there will not be enough volume for the LF drivers.

The other issue is if you try to make the angle too steep the sides will hit the compression driver. In this case the 25 degree side will requires part of the side to be a cut out to accommodate the DCX464 compression driver. It will be about 3mm from the outer edge of the box at one point.

With 25 degrees you can array two boxes to giving a total coverage angle of 110 degrees. At the same time the all LF drivers will be in close proximity to minimize phase cancellation etc.

In addition you will be able to arrange the boxes with tight-pack angles of 30, 40 & 50 degrees by using 15+ 15 degrees, 15 + 25, or 25 + 25 degrees boxes. While the reduced angles will have will comb filtering problems, it may be useful under some conditions … I need to do some testing first see how well it will work … but international deliveries are slow at the moment..

If and it’s a big IF you can array the boxes at these angle and get acceptable results you can then do different DSP settings for the various combinations and box numbers.

The other thing that will be different is the reflex port will be on the back of the box. This will cost a dB in LF efficiency but there will be improved phase response and less LF behind the box over the intended operating range … a little bit of passive directional control.
 
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Grant Manson

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This certainly sounds like a very interesting concept to chase!

I could certainly see it being used as a line array or sitting on a large point source stack with 2-3 giving good coverage and outrageous spl.
 
Jan 19, 2011
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Hi Grant, Chris & others,

One of the things I have tried to with my projects was to find solutions that are not generally provided by manufactures – The PM90 was designed to provide maximum SPL and quality on a pole mount speaker above 100Hz, The double 15” + Horn drum fill was to provide a double 15 that did not suffer from the typical comb filtering found with this combination, and the Double 10 was designed to be small, light and extremely powerful without compromise. I think RCF has now addressed this design with their new TT4.

The idea of this design is to do something different again, a box with two different angels – 25 degrees and 15 degrees. I don’t think any one has an angle as tight as 25 degrees … (?)

The reason to have two different angles is to get enough volume for the LF drivers. If you have two steep angles of 25 degrees or more there will not be enough volume for the LF drivers.

The other issue is if you try to make the angle too steep the sides will hit the compression driver. In this case the 25 degree side will requires part of the side to be a cut out to accommodate the DCX464 compression driver. It will be about 3mm from the outer edge of the box at one point.

With 25 degrees you can array two boxes to giving a total coverage angle of 110 degrees. At the same time the all LF drivers will be in close proximity to minimize phase cancellation etc.

In addition you will be able to arrange the boxes with tight-pack angles of 30, 40 & 50 degrees by using 15+ 15 degrees, 15 + 25, or 25 + 25 degrees boxes. While the reduced angles will have will comb filtering problems, it may be useful under some conditions … I need to do some testing first see how well it will work … but international deliveries are slow at the moment..

If and it’s a big IF you can array the boxes at these angle and get acceptable results you can then do different DSP settings for the various combinations and box numbers.

The other thing that will be different is the reflex port will be on the back of the box. This will cost a dB in LF efficiency but there will be improved phase response and less LF behind the box over the intended operating range … a little bit of passive directional control.


Looking forward to this!

To pass time I'm working on a dual 15" myself as a learning experience. And if it turns out ok, I have a new pair of speakers to gig with when this is all over :)
 

Chris Burns

Freshman
Nov 13, 2016
64
3
8
Connecticut
Hi Grant, Chris & others,

One of the things I have tried to with my projects was to find solutions that are not generally provided by manufactures – The PM90 was designed to provide maximum SPL and quality on a pole mount speaker above 100Hz, The double 15” + Horn drum fill was to provide a double 15 that did not suffer from the typical comb filtering found with this combination, and the Double 10 was designed to be small, light and extremely powerful without compromise. I think RCF has now addressed this design with their new TT4.

The idea of this design is to do something different again, a box with two different angels – 25 degrees and 15 degrees. I don’t think any one has an angle as tight as 25 degrees … (?)

The reason to have two different angles is to get enough volume for the LF drivers. If you have two steep angles of 25 degrees or more there will not be enough volume for the LF drivers.

The other issue is if you try to make the angle too steep the sides will hit the compression driver. In this case the 25 degree side will requires part of the side to be a cut out to accommodate the DCX464 compression driver. It will be about 3mm from the outer edge of the box at one point.

With 25 degrees you can array two boxes to giving a total coverage angle of 110 degrees. At the same time the all LF drivers will be in close proximity to minimize phase cancellation etc.

In addition you will be able to arrange the boxes with tight-pack angles of 30, 40 & 50 degrees by using 15+ 15 degrees, 15 + 25, or 25 + 25 degrees boxes. While the reduced angles will have will comb filtering problems, it may be useful under some conditions … I need to do some testing first see how well it will work … but international deliveries are slow at the moment..

If and it’s a big IF you can array the boxes at these angle and get acceptable results you can then do different DSP settings for the various combinations and box numbers.

The other thing that will be different is the reflex port will be on the back of the box. This will cost a dB in LF efficiency but there will be improved phase response and less LF behind the box over the intended operating range … a little bit of passive directional control.

I am patiently standing by to watch this evolve Peter. This is what I’ve been chasing since two years ago on here and the time is perfect now! Thanks. Interested in any and all info you can share on the journey. I may begin accumulating drivers etc as you provide it out. I’m going to repurpose my 4594s for this one. I have three just need one more. As for 12s we really have a plethora of options and that Ciara horn looks promising (similar to the XT1464 in design which I’ve been happy with, despite its very high end is lackluster but can’t have it all in this game!)


Sent from my iPhone
 

Joris Wijgerde

New member
Nov 29, 2019
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I am patiently standing by to watch this evolve Peter. This is what I’ve been chasing since two years ago on here and the time is perfect now! Thanks. Interested in any and all info you can share on the journey. I may begin accumulating drivers etc as you provide it out. I’m going to repurpose my 4594s for this one. I have three just need one more. As for 12s we really have a plethora of options and that Ciara horn looks promising (similar to the XT1464 in design which I’ve been happy with, despite its very high end is lackluster but can’t have it all in this game!)


Sent from my iPhone

Hi Chris,

May I ask what it is you don't like about the XT?
When I first tested it I wasn't very pleased myself, I found it to sound overly 'shouty'/honky at certain frequencies, even at low volumes. However, this soon proved to be caused by irregularities in my phase response. After clearing those up the sound changed dramatically. Now it sounds wide, clear and open at just about any volume.

As far as the HF response, here's a link to a recent measurement I did of mine. Please disregard the upward slope in the VHF, this was on purpose. No FIR, just some basic touch ups with EQ:
https://soundforums.net/community/threads/double-15-and-horn-drum-fill.211104/page-2#post-213959

Kind regards,
Joris
 

Peter Morris

Senior
May 8, 2011
1,061
146
63
Australia
Hi Joris,

For this project the XT1464 is too big. It sounds nice and can be used quite low so it was a good choice for the PM60. The only issue is that the pattern gets a bit narrow in the VHF region.

The Ciare PR614 has better HF pattern control and is one of the latest designs optimised for sound quality ... and its the right size for this project. It will go low enough but a bit more extension would be nice.
 
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Chris Burns

Freshman
Nov 13, 2016
64
3
8
Connecticut
Hi Chris,

May I ask what it is you don't like about the XT?
When I first tested it I wasn't very pleased myself, I found it to sound overly 'shouty'/honky at certain frequencies, even at low volumes. However, this soon proved to be caused by irregularities in my phase response. After clearing those up the sound changed dramatically. Now it sounds wide, clear and open at just about any volume.

As far as the HF response, here's a link to a recent measurement I did of mine. Please disregard the upward slope in the VHF, this was on purpose. No FIR, just some basic touch ups with EQ:
https://soundforums.net/community/threads/double-15-and-horn-drum-fill.211104/page-2#post-213959

Kind regards,
Joris

Hi Joris. I like the 400-10000 range but I find it really doesn’t propagate the VHF well and it kind of Peters out. I’m planning on bringing my box outdoors and doing a ground plane outdoor sweep as a baseline and then make the room tweaks separately. So far I’ve done both in one. These boxes are my Hi perf HT boxes. Quad 12s and a 4594 on the XT MMTMM design.


Sent from my iPhone
 
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