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Old 15th November 2011, 07:54 PM   #51
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No no no art I have two TH-18's...from the flat to 35 thread. I don't have the danley TH-118. Same exact external volume as the TH-118, most likely different folding. Similar to your keystone sub.

You're right the Danley only comes (came) with the 9600c, then the b&c, because (I heard) of reliability issues with the 9600c
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Old 15th November 2011, 07:56 PM   #52
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I can see how that is confusing with the naming. Sorry ! LoL
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Old 15th November 2011, 08:51 PM   #53
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Originally Posted by m R g S r View Post
No no no art I have two TH-18's...from the flat to 35 thread. I don't have the danley TH-118. Same exact external volume as the TH-118, most likely different folding. Similar to your keystone sub.

You're right the Danley only comes (came) with the 9600c, then the b&c, because (I heard) of reliability issues with the 9600c
My mistake.
The TH-18 is almost identical to the DSL TH-115/TH-118 folding, though the throat is a bit different.

The Keystone folding is quite different from the DSL TH-118, yet the frequency and phase response is quite similar due to similar path length, expansion, cabinet volume, and the same speaker :^).

At any rate, I'd expect the three cabinets to sound pretty similar, though DSL's sensitivity (and hence, max output calculated from sensitivity) seems way high when compared to sims and other commercial subs and my own comparison of the Keystone to a JBL SRX 728.

What amp(s) are you using to drive your TH-18 ?

Art
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Old 15th November 2011, 08:57 PM   #54
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That's what I meant (from posts of yours I've read, similar external volume etc...)
And yes the sensitivity of the authentic TH118 does seem high, maybe it's because of different test and or calculation methods. But I don't doubt Tom Danleys claims one bit!

I'm using a crown xti 4000 bridged. I'm guessing the subs receive a clean 1000 watts each in bridge mode. They deff make some noise without sounding stressed...I was very happy the 1 time I used them so far (I doubt they're even broken in yet!!)
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Old 16th November 2011, 01:51 PM   #55
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Originally Posted by m R g S r View Post
Mike...
I pm'ed you about my TH-18's. Hit me up if you want to check them out we can set them up!
Yes, I got your pm, thanks but 2 things, one I wrote to the dealer asking to listen to a demo here in my area in NY and two, I only need just one.
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Old 16th November 2011, 06:24 PM   #56
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Originally Posted by mikehende View Post
Yes, I got your pm, thanks but 2 things, one I wrote to the dealer asking to listen to a demo here in my area in NY and two, I only need just one.
Mike,

To integrate well with your existing sub, a TH or FLH will need completely different delay and EQ settings, and you will need to delay your HF cabinets to get the time alignment between them and the horn correct.

Without properly aligning subs to tops, they will lack impact and "punch", like your previous "mix and match" experiments.

Simply adding another of the cabinets you have, which if powered up to the same level, will add 6 dB, almost twice as loud.
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Old 26th December 2012, 05:32 PM   #57
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Originally Posted by teachjava View Post
I visited the factory in South Tacoma and got to see one being built. It's a dual isobaric tapped horn. It's an absolute monster, yet easy to move as it has handles built in and wheels. Oh, it's also narrower than a door.

Way to go guys!
Grrrr I didn't know McCauley was in Tacoma, now I *have* to see this thing! (I was born in Tacoma, and still have a house there.)
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Old 27th December 2012, 01:50 AM   #58
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Originally Posted by weltersys View Post
Efficient, small and low do not go together.
That stuff is not even close to the output of the Matterhorn, is a 40-driver, 40 kW self-powered Tom Danley designed tapped horn subwoofer which can produce 105 dB of output at 250 meters, with a response -3 dB at 12 Hz.

Matterhorn

Now that is a "gut wrenching sub".

As far as commercially available subs, DSL's DBH-218 has lots of punch, but not super deep extension.
Their TH-221 has loads of output and deep extension.

McCaully's 421 which uses four B&C 21" cones in a large isobaric tapped horn (they call it by another name, of course) does not go as low as the TH-221 (the 421 does not meet the published FR specs) but above 30 Hz is a real monster.
As you noted, the 421 does not play as low as the spec sheet claims.

I wonder if McCauley ran into the same problem that I ran into when I tried to make a TH too small? When i tried to do that, I found that it wasn't acting like a tapped horn at very low frequencies. I wasn't able to determine if the problem was my crappy construction technique. I have a hunch that tapped horns are a lot less forgiving to leaks when the horn size is very small. When I ran an impedance sweep on my very small tapped horn, I found that it didn't look like a TH at very low frequency. (Basically it was operating normally above 40hz, but below 40hz I wasn't seeing the deep narrow impedance dip that hornresp predicted.)

Here's some sims pitting the tiny Danley TH-Mini versus the McCauley M421. I'm using the measurements from my own personal clone of the Danley box, so it isn't exactly the same.

Click the image to open in full size.
here's an idea of what the inside of the th-mini looks like. It's just 4.7 cubic feet.

Click the image to open in full size.
here's cobrasound's measurement of a single and a double th-mini. Note the steep dropoff below 50hz.

Click the image to open in full size.
Here's a pair of McCauley M421s. These are big subs, about 42cf. In that foot print, you could fit nine(!) TH-Mins. OTOH, the McCauley has four six inch voice coils in that cab, so power compression should be pretty darn minimal.

Click the image to open in full size.
Here's the measured response of the McCauley, note my comments about "too small" tapped horns, and the lack of output below 25hz

Click the image to open in full size.
Here's a sim of the th-mini versus the McCauley, with one watt in half space. Note the following:

1) I'm only guessing at the folding scheme of the McCauley. I can make an educated guess by looking at the dips in the measured response, and the T/S parameters
2) Based on the looks of the basket and the dimensions of the voice coil, the driver is clearly the B&C 21SW152. You can buy a quad for $3400: B&C 21SW152 is a very high power 21" subwoofer for speaker subwoofer systems- B&C 21SW152 21" Subwoofer has a lightweight neodymium magnet - B&C 21SW152 21" high power speaker for speaker subwoofer systems has an xmax of 15.0mm. B&C 21SW152 high powe
3) McCauley claims sensitivity is 110dB, but I think that's exaggerated. From looking at the graph, the M421 is about the same sensitivity as the TH-Mini (100dB), it just plays a LOT lower. Some of the online reviews complained that the sub is 'flat' and 'compressed.' My hunch is that the reviewers felt it was compressed because the m412 isn't much more sensitive than smaller cabs, so if you're not listening to music that goes to 20hz, you might not appreciate the ULF output of the m412. (just my .02)


Click the image to open in full size.
Here's the displacement of the giant McCauley sub with 8000 watts into 4ohms, versus the TH-Mini with the same amount of power. Obviously, the TH-Mini isn't designed for this type of voltage, but I wanted to show the difference in excursion. With a little bit of tweaking and a high pass, it looks like the M421 can indeed take 8000 watts.

Click the image to open in full size.
Here's the output of the two boxes with 8000 watts. It seems to me that the McCauley's output is exaggerated by about ten dB. Danley's specs seems consistent with the predictions (a sensitivity of 100dB.)

Not saying the M421 is a bad box, but if it were me, I'd aim for an F3 that was half an octave higher, and with higher efficiency. M421 might be a cool sub for movie theatres, where the ULF is useful.
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Old 27th December 2012, 05:36 PM   #59
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Originally Posted by Patrick Bateman View Post
As you noted, the 421 does not play as low as the spec sheet claims.

I wonder if McCauley ran into the same problem that I ran into when I tried to make a TH too small?

Here's a sim of the th-mini versus the McCauley, with one watt in half space. Note the following:

3) McCauley claims sensitivity is 110dB, but I think that's exaggerated. From looking at the graph, the M421 is about the same sensitivity as the TH-Mini (100dB), it just plays a LOT lower...
It seems to me that the McCauley's output is exaggerated by about ten dB. Danley's specs seems consistent with the predictions (a sensitivity of 100dB.)

Not saying the M421 is a bad box, but if it were me, I'd aim for an F3 that was half an octave higher, and with higher efficiency.
I think the problem with the M421 from a sound quality and FR aspect may be related to the huge volume of air in the isobaric chamber.
The screen shot below shows the chamber on the left side, the outer speaker was removed to check if there was some physical problem that was resulting in the crappy sound.
IIRC, Hornresp does not have a parameter for the enclosed "isobaric" volume, that area being excessive may result in a low frequency simulation lower than the measured response.

Your sim shows much lower response than the 421's 27 Hz F3, which would also make your sim's output much lower than actual.

McCauley claims sensitivity of 110dB with a 2.83 volt input to a 2 ohm box, one watt one meter sensitivity would only be 104 dB.

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Old 28th December 2012, 12:04 PM   #60
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I only know Wayne's sub (2x12"). I don't know if it can compete in the same race. He and Danley are two best designers.
Bass Horn subwoofer
AudioRoundTable.com: Pi Speakers => Pi 12 sub plns please?
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