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Old 26th September 2012, 07:21 PM   #1
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Location: Calgary on the Bow
Default Brute force in a small cabinet...

I saw this cabinet design and wondered if any here had ever built similar done simulations of heard anything like this? The size is good if it does what is claimed and you might be able to find 8 cost effective drivers for a reasonable cost? I normally don't gravitate toward the bruit force approach but this does look interesting. Any comments would be most welcome. Thanks and best regards Moray James.
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File Type: jpg Horn Four driver Hybrid.jpg (96.4 KB, 251 views)
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Old 26th September 2012, 09:13 PM   #2
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The short horn and high Fb make it a good "kick bin", but a tapped horn can more effectively do the same in a given space.

The frequency response curve given may not be representative of the actual response , I'd expect more in the 160-200 Hz range from this type of cabinet.

If a 50 Hz Fb is low enough for you, look at the Tham or SS15, if you want low end to extend to 35 Hz (as most modern music does) look at XOC1's TH18 or my Keystone design.

If you want real LF going down to the 20 Hz range, look at the Gjallerhorn.

Art Welter
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Old 27th September 2012, 05:46 AM   #3
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Thank you Art: I have been looking at possible alternates to my Peavey FH-1 bin which is a slightly bigger LaScala for all intent, so 50 Hz to 500 range would be great Something like this would likely be 3 or so db lower in efficiency than the FH-1 but this cab would have plenty of power handling and would be reasonably efficient and could possibly be physically smaller. It is not too far different from the EV MTL4 with the plenum opened up and out some to make a shallow horn. Thanks again for the input. Best regards Moray James.
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Old 27th September 2012, 02:32 PM   #4
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Been trying to wrap my head around this for a little while now, to me it seems like a tapped horn with a huge throat chamber, so you could attempt to model it like that. Not a ported horn or bandpass horn.

Here you go, very similar idea:

Chambered Tapped Horn Or 6th order series tuned bandpass. - Realm of Excursion
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Old 27th September 2012, 06:14 PM   #5
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Turbodawg: thanks, yes the vent seems way too short given the diametre to be able to tune at any usable frequency. As a TH the path looks way to short to make a 1/8 wave line also. I have no way to know if this design actually works as stated so I figured I would ask around. Will give your link a read thank you . Best regards Moray James.
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Old 27th September 2012, 08:28 PM   #6
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Quote:
Originally Posted by moray james View Post
Turbodawg: thanks, yes the vent seems way too short given the diametre to be able to tune at any usable frequency. As a TH the path looks way to short to make a 1/8 wave line also.
Moray James.
The "horn" is also a deep flared port.
In Hornresp one can't change port angle, so modeling the cabinet in post #1 as a TH would be more appropriate as Moray said.
For LF output, the MTL-4 manifold plenum gives up far less internal volume, I'd expect the cabinet in post #1 to have a much steeper upward response and less LF than the MTL-4 or the simulated response.

In the mid 1980's I designed a cabinet called the L-4, which used four Electro Voice EVX150 15" "V" loaded with a 30" depth.
I use the term "designed" a bit loosely, we cut down 16 of the original L-4 straight horns of 45" depth and converted them to a combination horn/BR. The design turned out to be quite successful for the time.
Though the EV MTL-4 design was slightly smaller in volume and had similar LF, the upper response of the L-4 was subjectively better in sound quality, a more visceral "punch", and loads of upper bass headroom.

The cut down L-4 was a result of the brand-new MTL-4 spanking the LF output of the straight horn L-4 (which only had EV 15B speakers at the time) in a side by side test at Prince's Paisly Park soundstage. Rob Colby had driven the 15Bs in to hard clipping, the 100 watt voice coils started to expand and scrape and make horrible sounds. I thought not only had we lost the Prince tour, we would be reconing 16 speakers, fortunately after they cooled down they worked fine.
That walk of shame, and 45" depth being too deep to fit behind the fire curtain on many stages prompted the change, which resulted in way more LF in a 1/3 smaller package.

The L-4 response as you can see, tilts upwards more than 10 dB from Fb. The response peaked even higher than the graph below shows, IIRC a 24 dB per octave LR at 200 Hz was used. The LF was probably not affected by the Brooke-Siren FDS-340 LP which was fixed at 20 Hz !

Recently I modeled the L-4 in Hornresp, it did not show nearly as much upper response as the actual measured response.

Art Welter
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File Type: jpg L4 200HzLP.jpg (27.6 KB, 150 views)
File Type: jpg L4.jpg (25.8 KB, 145 views)
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