No, but it is easy enough to simulate as it can be approximated as one long straight horn with side exit. Question is where should the exit go? Bottom? Up? You can get deeper bass extension but it may not be as smooth. With one horn you can use Hornresp to model easily enough even. What driver and size overall were you thinking of? Note that channel width will be very narrow if you want to get extra path length. This may add horn like peaks and harmonic distortion. It will sound like a brass horn full of harmonic content.
Allright, internet is back 
Amazing how much you depend on it huh?
X, I am thinking about scaling it up a bit. If I make it 36" from the original squared off horn drawing and make it 5" deep, would that work or do you have other suggestions? Like would that make the driver chamber the right size or...
Is 32" enough or...
I would use thin ply front and back like before.
Amazing how much you depend on it huh?X, I am thinking about scaling it up a bit. If I make it 36" from the original squared off horn drawing and make it 5" deep, would that work or do you have other suggestions? Like would that make the driver chamber the right size or...
Is 32" enough or...
I would use thin ply front and back like before.
Cornu for RS 40-1254
Cal,
Your hunch on sizing it was good. The RS 40-1354 will work very nicely in a 36 in x 5 in deep Cornu. Here are the simulation results assuming good amount of stuffing in the driver chamber and light-to-moderate stuffing in the channels up to split point. Mount the speaker 53 in (at centerline) above the floor to minimize floor bounce null. Let us know how the build goes and good luck!
X
SPL vs Freq:
Cone displacement:
Impedance:
Cal,
Your hunch on sizing it was good. The RS 40-1354 will work very nicely in a 36 in x 5 in deep Cornu. Here are the simulation results assuming good amount of stuffing in the driver chamber and light-to-moderate stuffing in the channels up to split point. Mount the speaker 53 in (at centerline) above the floor to minimize floor bounce null. Let us know how the build goes and good luck!
X
SPL vs Freq:
Cone displacement:
Impedance:
Attachments
I'm slowly getting there.
Making the plan was very time consuming as is the transfer or the plan in the MDF.
Still figuring out how to make the speaker connections...
Making the plan was very time consuming as is the transfer or the plan in the MDF.
Still figuring out how to make the speaker connections...
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
I calculated the throat At area with : (where c is the speed of sound)
At=(2*Pi*Fs*Qts*Vas)/c
At=[2*3,1416*58*0,52*31*10^(-3)]/343
At=0,0171 m²
At=171 cm²
The thing is as there are two throats in the Cornu speaker cavity, I believe you have to divide this by two??? Or is it the ideal throat area whatever the numbers of horns for a driver???
Thanks in advance for your help.
At=(2*Pi*Fs*Qts*Vas)/c
At=[2*3,1416*58*0,52*31*10^(-3)]/343
At=0,0171 m²
At=171 cm²
The thing is as there are two throats in the Cornu speaker cavity, I believe you have to divide this by two??? Or is it the ideal throat area whatever the numbers of horns for a driver???
Thanks in advance for your help.
Edodo,
What size did you end up making your baffles? The throat area will be set by the overall scaling of the Cornu (which sets the gap width of the the throat as the distance between the channels at the driver chamber) and the depth if the channel. In general the area of the throat is set approximately equal to driver Sd but can be smaller. I have been a little busy lately so could not run the sim for you to determine the channel depth but have some time today. This depth controls the amount of bass and can be used to balance the treble depending on driver efficiency. Great progress by the way!
X
Edit: I see the drawing shows 74cm and the driver cutout appears to be bigger than driver chamber - meaning you will have to cut away at the channels and reduce their length and widen the throat gap. Is that true? This may make the sims more tricky as I cannot simply scale the design with a single variable. From the looks of it, you will not have any channels leading to the bifurcation - all will have to be removed up to that point to fit the driver which probably would have required a 36 to 42 in Cornu.
What size did you end up making your baffles? The throat area will be set by the overall scaling of the Cornu (which sets the gap width of the the throat as the distance between the channels at the driver chamber) and the depth if the channel. In general the area of the throat is set approximately equal to driver Sd but can be smaller. I have been a little busy lately so could not run the sim for you to determine the channel depth but have some time today. This depth controls the amount of bass and can be used to balance the treble depending on driver efficiency. Great progress by the way!
X
Edit: I see the drawing shows 74cm and the driver cutout appears to be bigger than driver chamber - meaning you will have to cut away at the channels and reduce their length and widen the throat gap. Is that true? This may make the sims more tricky as I cannot simply scale the design with a single variable. From the looks of it, you will not have any channels leading to the bifurcation - all will have to be removed up to that point to fit the driver which probably would have required a 36 to 42 in Cornu.
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Thanks X. Yes I loose the inner channel but I redraw the first canal so that I have the channel before the bifurcations. I didn't do the depth already and really I'm wondering what your Sims can end up with.
At the end I scaled the drawing to have 60cm wall to wall instead of this plan 70cm... I know its little but I wanna experiment first with cheap wood. If its not satisfactory I will increases size with proper veneered wood later.
PS: I did get my throat area formula from the horn design paper found in this thread. Still I wonder if I should divide this in two for each throat...
At the end I scaled the drawing to have 60cm wall to wall instead of this plan 70cm... I know its little but I wanna experiment first with cheap wood. If its not satisfactory I will increases size with proper veneered wood later.
PS: I did get my throat area formula from the horn design paper found in this thread. Still I wonder if I should divide this in two for each throat...
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Edodo,
How much channel do you have left before bifurcation ? The throat area is total so includes both channels. 60cm is on small side and not having full length leading to bifurcation will reduce your bass extension. I can run a case at 60 cm with a short say 5 cm long channel leading to bifurcation. My guess is depth will be about 4.5 to 5 inches.
How much channel do you have left before bifurcation ? The throat area is total so includes both channels. 60cm is on small side and not having full length leading to bifurcation will reduce your bass extension. I can run a case at 60 cm with a short say 5 cm long channel leading to bifurcation. My guess is depth will be about 4.5 to 5 inches.
Uh-oh.
I guess the other thing to do is to build the driver chamber on the front and cut out the right size hole so you don't have to shorten the channels.
The '74cm' was on the original drawing so that's not necessarily the size.