Thank you so much Patrick for your input. I'm used to large boxes as you can see, so that's not an issue. The reason I want to try a TH is 1) Fewer drivers. 2) Less power consumption due to less sub amps. 3) Able to play down to 20hz (I know it's inaudible). 4) Hopefully produce SERIOUS ULF's (ultra low freq.)... TH amp has remote gain control on dash and switch to only use it when I want.
So aside from the no free lunch bit, could 2 12's or a single 15" sub fit in a TH with max outer dimensions of 72" long x 65" wide x 18" high (roughly 49 cubic feet) and still be able to play down from 30hz to as low as possible?
And if it makes any difference I'm looking at the Sound Splinter RL-S series to do this. Here's the specs for the 15:
Qts: 0.953 Mounting Depth: 25.5 cm Qes: 1.114 Total Depth: 26.8 cm Qms: 5.712 Outside Diameter: 40 cm Fs: 25.51 Hz Weight: 49 lbs Re: 2.92 Ohm Magnet Width: 18.8 cm Ls: 2.445 mH Mounting Cutout: 35.8 cm Rp: 2.81 Displacement: 0.22 cu ft Vas: 85.37 L
Mms: 491.4 g
Cms: 79.18 u
Bl: 14.18 T*m
SPL: 82.8 dB
Sd: 0.0876 m^2
Xmax: 38.5 mmAnd here's the specs on the 12:
Single 3 Ohm Measurements Qts: 0.970 Mounting Depth: 21.2 cm Qes: 1.114 Total Depth: 23.3 cm Qms: 7.459 Outside Diameter: 32.3 cm Fs: 30.97 Hz Weight: 44 lbs Re: 2.88 Ohm Magnet Width: 18.8 cm Ls: 2.54 mH Mounting Cutout: 28.2 cm Rp: 3.15 Displacement: 0.19 cu ft Vas: 27.65 L
Mms: 344.2 g
Cms: 76.69 u
Bl: 13.15 T*m
SPL: 80.5 dB
Sd: 0.0507 m^2
Xmax: 38.5 mm
Obviously the 15" has the lower Fs, but not sure how this plays into a tapped horn and Hornresp is new to me and not sure how to input this into it.
Qts: 0.953 Mounting Depth: 25.5 cm Qes: 1.114 Total Depth: 26.8 cm Qms: 5.712 Outside Diameter: 40 cm Fs: 25.51 Hz Weight: 49 lbs Re: 2.92 Ohm Magnet Width: 18.8 cm Ls: 2.445 mH Mounting Cutout: 35.8 cm Rp: 2.81 Displacement: 0.22 cu ft Vas: 85.37 L
Mms: 491.4 g
Cms: 79.18 u
Bl: 14.18 T*m
SPL: 82.8 dB
Sd: 0.0876 m^2
Xmax: 38.5 mmAnd here's the specs on the 12:
Single 3 Ohm Measurements Qts: 0.970 Mounting Depth: 21.2 cm Qes: 1.114 Total Depth: 23.3 cm Qms: 7.459 Outside Diameter: 32.3 cm Fs: 30.97 Hz Weight: 44 lbs Re: 2.88 Ohm Magnet Width: 18.8 cm Ls: 2.54 mH Mounting Cutout: 28.2 cm Rp: 3.15 Displacement: 0.19 cu ft Vas: 27.65 L
Mms: 344.2 g
Cms: 76.69 u
Bl: 13.15 T*m
SPL: 80.5 dB
Sd: 0.0507 m^2
Xmax: 38.5 mm
Obviously the 15" has the lower Fs, but not sure how this plays into a tapped horn and Hornresp is new to me and not sure how to input this into it.
Once you place your speaker enclosure inside a car everything changes. Since the dimensions of a normal car are acoustically significant, the free space models are not applicable any more. PWK drones on and on about this. He has written a modeling program that can take in account the car's interior on the speaker enclosure’s frequency response. If you think about it, in a car we are taking an enclosure and placing it into another enclosure. I've seen a Soundstream XXX-15 almost destroy a BMW 5 series. It ripped the trunk latch rivets completely out. Then the same enclosure was put into a Saturn Vue with the same amp, but it was weak in comparison. Sure it still moved air, but it didn't have the same results as it did in the BMW. The most successful designs are car model specific.
As a general 'rule of thumb', I design tapped horns so that the tuning frequency is about 0.707 times the FS. This isn't a hard and fast rule, but it helps me 'get in the ballpark' before I start to do serious number crunching with hornresp.
With an FS of 25.51hz, I'd be looking at a tapped horn tuned to about 18hz. Seriously, this is why nearly all of my in-car tapped horns were eights. An eighteen hertz sub is just pointlessly large for a car. I've literally loaded music files into audacity, and there is no content below 30hz in most music.
In other words, what's the point of an 18hz tapped horn if your music doesn't go to 18hz?
Also, this is something which is very specific to horns. Horns are bandpass boxes. And since they're bandpass boxes, their efficiency is highest over a narrow range.
The only real advantage to using twelves or fifteens in a car audio tapped horn is if you're in the habit of listening to infrasonic music, or you play a lot of movies in the car. If that's the case, a 15" tapped horn (might) make sense.
But even that's an edge case, and if I were building a car audio system that needed to go down to 18hz, I'd likely uses a single infrasonic sub to cover 15hz to 30hz, and then a much more powerful sub to cover 30hz and up.
Getting the octave from 40hz to 80hz is what's tricky in car audio. Getting 20 to 40hz right is easy, because of cabin gain. And on top of that, there's really nothing down there, unless you're in the habit of listening to sound effect CDs, classical music, or movies in the car.
If you listen to 'regular' music, like 90% of us, an 18hz tapped horn is pointless in a car. (Now in a *home* is a different story, and I have a 300lb tapped horn in my closet, which is great for movies.)
Hi Speedcult,
Besides the fact that Patrick Bateman is obviously correct, if you want to build something as you are describing it in Post #341: "...TH with max outer dimensions of 72" long x 65" wide x 18" high..."; then it sounds like the DTS-10 should fit your bill (44 x 59.5 x 16), and it seems to be available again as a kit:
Danley DTS-10 "Super Spud" DIY kit - AVS Forum
I'll also attach a very quickly done Hornresp input using your Sound Splinter 12" T/S data:
Regards,
Besides the fact that Patrick Bateman is obviously correct, if you want to build something as you are describing it in Post #341: "...TH with max outer dimensions of 72" long x 65" wide x 18" high..."; then it sounds like the DTS-10 should fit your bill (44 x 59.5 x 16), and it seems to be available again as a kit:
Danley DTS-10 "Super Spud" DIY kit - AVS Forum
I'll also attach a very quickly done Hornresp input using your Sound Splinter 12" T/S data:
Regards,
I looked the design's over.
They are interesting. Mostly tuned flared port designs similar to the one in this thread.
Neither are horn's. They can provide about 3 to 4 db gain in the speakers output. Noticeable but not night and day difference.
Patrick's remark about a horn being larger is true. A real horn be it a tapped horn or a front loaded horn will be larger than an equivalent vented enclosure tuned to the same Fs.
What a horn can do is give you more output per watt.
And what a really good horn can do is greatly lower the levels of distortion coming off of your driver.
They are interesting. Mostly tuned flared port designs similar to the one in this thread.
Neither are horn's. They can provide about 3 to 4 db gain in the speakers output. Noticeable but not night and day difference.
Patrick's remark about a horn being larger is true. A real horn be it a tapped horn or a front loaded horn will be larger than an equivalent vented enclosure tuned to the same Fs.
What a horn can do is give you more output per watt.
And what a really good horn can do is greatly lower the levels of distortion coming off of your driver.
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If you provide him with accurate information about your car, then the results line up very well with his modeled predictions.
None of his designs are horns in the true sense. The ducts that are used in some of his designs resemble horns in their shape. This is more a matter of semantics. Remember, he is originally from Warsaw, Poland so his jargon differs from what most of us would use. Even though he speaks English like the rest of us, sometimes you have to put on your Pete translator cap.
Oh he is intelligent enough. He does good quality work and makes sense in his designs.
Nothing bad to say about that.
He is very good at promotion. Again all the more power to him. And I wish him well.
His video scares me the way he cuts things out. Not well trained on a table saw.
Other than that looks good.
Nothing bad to say about that.
He is very good at promotion. Again all the more power to him. And I wish him well.
His video scares me the way he cuts things out. Not well trained on a table saw.
Other than that looks good.
please explain your thinking.
hows that done? how does, how could knowing a vehicles internal volume/physics impact the end result in the way a subwoofer works in a specific box/vehicle?
lets use a jbl 12" subwoofer as an example,
how would/could the 3 boxes be different
same driver.
1.jbl recc enclosure
2.small vehicle
3.mini van.
Minute movements in a woofers location in the enclosure within the vehicle are just a bit on the suspect side of things.
Consider this that the quarter of a wavelength in frequency is where things start to effect the listening environment.
Within a car you are always less than a quarter wavelength away from the box when it comes to bass. Second you are in the pressure field a completely different environment than in a free listening environment like a living room where you cannot literally pressurize the room you are listening in.
But given a cars known internal volume you can make changes in the size of woofer and the tuning frequency to make the most out of the least.
Consider this that the quarter of a wavelength in frequency is where things start to effect the listening environment.
Within a car you are always less than a quarter wavelength away from the box when it comes to bass. Second you are in the pressure field a completely different environment than in a free listening environment like a living room where you cannot literally pressurize the room you are listening in.
But given a cars known internal volume you can make changes in the size of woofer and the tuning frequency to make the most out of the least.
Wow what a thread, just finished reading it from start to finish. I learned so much and on the other hand I realize how much I do not know. I have been debating on what to do with my car. Then I stumbled onto some different threads about subs based on the designs discussed in this thread. I do not have alot of amp power and wanted something efficent. I have an old ADS PH15.2, its a 6 channel amp that has made its rounds in all of my past systems starting back in 1993 when I purchased the amp used. My car is a 08 Suzuki SX4 Sport sedan. The problem I have is that the rear speakers are mounted in the rear doors and the seats do not fold down. Would a horn type of subwoofer work well if it was in the trunk? The unhorn looks like it could do the trick if I used two of them but it may be a bit to big to fit under the front seats. The space under the seat is quite spacious. I will have to take some measurements to be sure. Could that box be made with 5-1/4 inch subs? My amp does not have a crossover of any kind the only adjustment is a gain for Channel 1-2,3-4,5-6. Mark you said that if you play a source that has the really low notes in them the sub could be blown or it would cause it to sound really bad, did I get that right? If so what would be the best way to protect the sub and prevent it from playing the really low notes to begin with? I figured that if I had one under each seat it would be more that what I would really need, but could help to reinforce the deep bass. I listen to pretty much anything, I do music that I can feel. If I can figure out the lows all i have to figure the front stage. I am trying to keep the budget as small as possible.
Thank you in advance for your time.
Respectfully Phil
Thank you in advance for your time.
Respectfully Phil
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