Haha. I may have trouble sourcing them. Maybe I will do 36 inches square with the FF125.
Brad
So after many weeks of reading and planning I completed my first Cornu. With about $40 or so in supplies and some 4" midrange drivers from a set of old garbage speakers. I had to add a tweeter to handle to top end. Dimensions are 27.5 x 27.5 with a front baffle that's 2 inches larger.
How do they sound? Well they exceed my expectations in some regards but not so much in others. I feel that the size I made would fare better in a larger room. Bass output is pretty good but they shine mostly at moderate volume with music more focused on vocals. Nora Jones sounds sounds amazing as does Dave Mathews. Heavy rock and pop not so much. I kinda screwed myself for future tuning as I had to hot glue the driver to the baffle. Made for a great seal but it's a done deal the way they sit. Thanks to "X", Cal and others for all the time you've put into this thread to make this possible. If I ever get time to hop on the laptop I will post some pics. Next up some 2-way foam core TQWT's. I will have to take a swing at another Cornu at some point with some TC-9's or Faital Pro drivers.
Wes
How do they sound? Well they exceed my expectations in some regards but not so much in others. I feel that the size I made would fare better in a larger room. Bass output is pretty good but they shine mostly at moderate volume with music more focused on vocals. Nora Jones sounds sounds amazing as does Dave Mathews. Heavy rock and pop not so much. I kinda screwed myself for future tuning as I had to hot glue the driver to the baffle. Made for a great seal but it's a done deal the way they sit. Thanks to "X", Cal and others for all the time you've put into this thread to make this possible. If I ever get time to hop on the laptop I will post some pics. Next up some 2-way foam core TQWT's. I will have to take a swing at another Cornu at some point with some TC-9's or Faital Pro drivers.
Wes
Wes,
Thanks for sharing. They can be very rewarding when done right. Sounds like you are part, if not most of the way there. I am thinking my next will be a 6.5" driver in a 42" Cornu and then maybe a 48" with an 8" driver. Who knows, all I have gathered is that X started me down a path and the further I go, the further I want to go. Bigger is so much better with this box.
Cheers.
Thanks for sharing. They can be very rewarding when done right. Sounds like you are part, if not most of the way there. I am thinking my next will be a 6.5" driver in a 42" Cornu and then maybe a 48" with an 8" driver. Who knows, all I have gathered is that X started me down a path and the further I go, the further I want to go. Bigger is so much better with this box.
Cheers.
It's pretty forgiving. Anywhere from 3in to 6in can work. I would pick 4.5in though. You can use stuffing to adjust balance between bass and treble to suit your taste later.
Cheers Xkr,
Any guidance regarding the ideal compression chamber size?
Looks like I am going to go for a 40 inch square build now. I'm going to be cutting from 8x4 panels, so bigger squares are better value.lol.
Will be taking these on a plane as checked in luggage and I have up to 32kg to play with and 1.7m x 1.2 x 1.2.
Brad
Any guidance regarding the ideal compression chamber size?
Looks like I am going to go for a 40 inch square build now. I'm going to be cutting from 8x4 panels, so bigger squares are better value.lol.
Will be taking these on a plane as checked in luggage and I have up to 32kg to play with and 1.7m x 1.2 x 1.2.
Brad
If you follow the pdf plan scaled up, the chamber size is dictated in area by the 40in scale and in depth by what you set the thickness as. So you do not need to worry about it. Just make sure your magnet and basket clears the chamber side walls.
40 inch, that's huge! the FE103 already looks small in my 24inch cornus, in a 40 it'll look tiny. Really curious how they'll turn out.
cheers Coen,
will post my experiences with this as they happen.
have been looking at the scalable drawings. looks like 600% enlargement will give me the 40" dimension that I need.
I Will be definitely building in a way that will give me easy access to add extra stuffing, as think that will be needed.
Brad
will post my experiences with this as they happen.
have been looking at the scalable drawings. looks like 600% enlargement will give me the 40" dimension that I need.
I Will be definitely building in a way that will give me easy access to add extra stuffing, as think that will be needed.
Brad
Here is a sim of the FE103E in a 40in x 4.5in Cornu, mounted at 1.2m centerline from the floor. Looks pretty good with deep 45Hz bass extension. You may need a tad BSC to tame the HF.
Here is the impedance:
Here is the cone displacement - you may run into over-excursion here.
I think if you made a typical 75cm wide (29.5in) x 4.5in deep Cornu, the displacement goes to about 1.5mm at 70Hz and you get a higher level of bass amplitude with bass extension down to 55Hz:
Here is freq response of a 29.5in Cornu:
My recommendation is that you make a smaller 29.5in for your first Cornu and look for a bigger driver for a 40in (like a 6.5in full range). It's a lot of materials and extra work to make a 40in vs a 29.5in.
You can go with the 40in but be careful with cone excursion and don't play it with music that has low freq content at high volumes. If you have an active EQ, you can limit the content by high passing at 50Hz or so.
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That's great. Thankyou XKR971
I really like the smoother response in the 40 inch simulation, but can see the excursion problem as well. I suppose I could add in an active high pass stage to protect the driver.
That 27 inch response does have a slightly more uneven response. I wonder if maybe 36 inches would be a good compromise. The 40 incher would of needed 3 x 8x4 sheets of plywood and I am pretty sure that I can build at 36 inches square from 2 sheets.
Brad
I really like the smoother response in the 40 inch simulation, but can see the excursion problem as well. I suppose I could add in an active high pass stage to protect the driver.
That 27 inch response does have a slightly more uneven response. I wonder if maybe 36 inches would be a good compromise. The 40 incher would of needed 3 x 8x4 sheets of plywood and I am pretty sure that I can build at 36 inches square from 2 sheets.
Brad
I keep coming back to this thread, especially because of my first attempt, and the high WAF!
I was wondering, has a version for the FaitalPRO 3FE25 been created? I'd like to make something less obnoxious than my current TV/HT speakers (Cerwin-Vega MTMs that have a lacking midrange).
I may make a sub to couple them with.
Thanks in advance!
Dan
I was wondering, has a version for the FaitalPRO 3FE25 been created? I'd like to make something less obnoxious than my current TV/HT speakers (Cerwin-Vega MTMs that have a lacking midrange).
I may make a sub to couple them with.
Thanks in advance!
Dan