Hey Guys
I have 2 of the RCF L18P200-N drives laying around and i would like to build a traped horn to put them in, if its posible to get one cap to go from 35hz(ish) to 120hz and around a 100-101db spl minimum in the bandpas it would be soooo sweed!
They have good power handling (800w AES) and a large xmax (9,8mm) and i can get 2 more pretty cheap 🙂
Is this posible ? is there a designe that will do this or am i looking at making a new designe?
Cheers Toby
(sorry for my bad english)
Same post on speakerplans.com...
I have 2 of the RCF L18P200-N drives laying around and i would like to build a traped horn to put them in, if its posible to get one cap to go from 35hz(ish) to 120hz and around a 100-101db spl minimum in the bandpas it would be soooo sweed!
They have good power handling (800w AES) and a large xmax (9,8mm) and i can get 2 more pretty cheap 🙂
Is this posible ? is there a designe that will do this or am i looking at making a new designe?
Cheers Toby
(sorry for my bad english)
Same post on speakerplans.com...
stock sensitivity is 96 db/1W/1m. A 5-dB increase won't happen while staying reasonably flat from 35ish all the way to 120 in a tapped horn. You want an increase in sensitivity, FLH in groups of 4 is the way to go. But you won't get down to 35Hz unless you use a massive horn length. Hoffman's Iron Law. It would be nice if we all could simply specify the -3dB corner frequency AND an arbitrary sensitivity and have the laws of physics conform around us. 🙂
With the right 96 dB speaker a TH can do 101 dB one watt one meter at 35 Hz and around 104 dB at 120 Hz.
The DSL TH-118 does, at 40 x 22.5 x 28 inches is not particularly massive.
A quarter wave length of the FC in a TH design does not require a huge mouth, so can be folded in to a relatively small enclosure.
Well I feel dumb. Really. I had been used to modeling using only 2V input in Horn Resp due to me simulating some "mobile audio" speakers recently. Let me see what a correct 2.83V input shows now. 🙂
The less the Re of a speaker, the louder it will show in Hornresp.
Some "4 ohm" speakers really are more like 3 ohms.
Most amps do not quite double the power at 1/2 the impedance, so a four ohm speaker may not actually play 3 dB louder than an 8 ohm.
Djk what design is that?
Also on speakerplans.com i have been sugestet the cyclobs (CB-18) you thing that the l18p200 will work on fullpower 800w in that one?
I know that the sens is low at 96db/1w but it should bee posiblel i think 🙂
Also on speakerplans.com i have been sugestet the cyclobs (CB-18) you thing that the l18p200 will work on fullpower 800w in that one?
I know that the sens is low at 96db/1w but it should bee posiblel i think 🙂
"Djk what design is that?"
That is a design I did for an 18 Sound woofer that I modified slightly for your RCF driver.
"Also on speakerplans.com i have been sugestet the cyclobs (CB-18) you thing that the l18p200 will work on fullpower 800w in that one?"
I think it should work OK, you notice that I was the one that suggested the Cyclops over there (I'm _djk_ over there).
"I know that the sens is low at 96db/1w but it should bee posiblel i think"
It looks like the TH adds about 5dB, so it should do what you need it to. The AkAbak script I posted is of one TH, a pair would smooth out a bit. Here is one, two, and four or a 40hz 15" design just to show how things change.
That is a design I did for an 18 Sound woofer that I modified slightly for your RCF driver.
"Also on speakerplans.com i have been sugestet the cyclobs (CB-18) you thing that the l18p200 will work on fullpower 800w in that one?"
I think it should work OK, you notice that I was the one that suggested the Cyclops over there (I'm _djk_ over there).
"I know that the sens is low at 96db/1w but it should bee posiblel i think"
It looks like the TH adds about 5dB, so it should do what you need it to. The AkAbak script I posted is of one TH, a pair would smooth out a bit. Here is one, two, and four or a 40hz 15" design just to show how things change.
djk sorry did not notis that you were on speakerplans ;P
The grafs you are showing is that your design or the cyclobs?
Also du you have the plans for that design of yours?
bjorno how dos that design look? it seems to run out of xmax to soon?
The grafs you are showing is that your design or the cyclobs?
Also du you have the plans for that design of yours?
bjorno how dos that design look? it seems to run out of xmax to soon?
It looks like the TH adds about 5dB, so it should do what you need it to. The AkAbak script I posted is of one TH, a pair would smooth out a bit. Here is one, two, and four or a 40hz 15" design just to show how things change.
djk, with regards to your Akabak script, I have never seen a TH modeled that way. I had read that generally speaking, one does not want to terminate a waveguide with a horn, but rather one shoud end a series of waveguides with a radiator. Also what are the length of the sections of that TH? I only see "two" sections, one at 2.6m, and one at 0.30m. Is it indeed a total of 2.9m or is there something I'm not seeing?
The Cyclops has a different throat than the usual TH, therefore it is modeled as a small volume (12L) coupled to a large throat (800cm).
You are seeing the lengths properly.
You are seeing the lengths properly.
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Thx epa...
hmm seems like my drivers won't do that well in the CB-18 runs out of xmax way to soon...
hmm i need a new design for my drivers.. im getting crasy of trying my own designs in hornrsp...
hmm seems like my drivers won't do that well in the CB-18 runs out of xmax way to soon...
hmm i need a new design for my drivers.. im getting crasy of trying my own designs in hornrsp...
Unless you are running sine wave sweeps you are not likely to run into excursion problems, just run a high-pass filter at the cut-off point of the cabinet.
Probably, 35hz might be OK too. If your crossover can do a Chebychev that would be 0dB down at the cut point that would be nice too.
if u want to reproduce 35 hz ur hp schould be @ 30 butterw (imo)
if u want i can design someting,if u specify some dimensions.
