Another Hopeless Attempt At Reverse Engineering a Danley Design - diyAudio
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Old 25th September 2014, 04:29 AM   #1
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Default Another Hopeless Attempt At Reverse Engineering a Danley Design

Danley posted some pics on his Facebook of a new sub today.
These things are truly getting silly, this one is designed to be assembled into a 10' tall array. While everyone else is getting cardioid response with digital trickery, Danley is doing it with a sub that's taller than the room you're sitting in :O

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This pic gives you a good idea of the horn folding. We can use this to guess what the response, output, and F3 is like.

[img]
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Old 25th September 2014, 04:38 AM   #2
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Here's my guess at the folding. We know that the width is 5'.
A 5' long duct resonates at 56.25hz. So there's either one fold (28hz) or two folds (19hz).

Since they said it's good for 20hz, I'm guessing two folds, but I may be wrong. It may be a single fold.

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Here's my guess. I'm basing this on what the mouth looks like, and where the woofers are mounted. (We can tell from the access panels.)

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Here's a hornresp model of my guess, using the 18 Sound 18NLW9600

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Here's the predicted output with 7,200 watts into 3.3 ohms.
Yowza that's a lot of bass.
With four in an array it should be possible to exceed 150dB(!)
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Old 25th September 2014, 04:46 AM   #3
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Click the image to open in full size.
There's a brutal dip in the predicted output.
Then again, arraying horns smooths out the response, as illustrated above.

Also, this is something I haven't heard discussed much, but horn dips and peaks are harmonic. For instance, if you're listening to a recording with a drum strike at 22hz, there will be harmonics at 44hz, 66hz, etc. And a horn sub keeps those harmonics intact.

On the flipside of this, if there's a drum strike at 35hz, where the horn has a big dip, the harmonics at 70hz will come through loud and clear.

IE, it's worse to have a peak or dip at 80hz than at 25hz. If you have a peak or dip at 80hz, it's going to screw up the sound of all the fundamentals at 40hz. (Because 80hz is a harmonic of 40hz.)

But a peak or dip at 35hz isn't going to cause any audible issues. If there's a sound at 35hz you'll hear the harmonic at 70hz.

True, we'd LIKE to have flat response to 20hz, but it's better to have a peak or dip at 35hz than at sixty, seventy, or eight hertz.
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Old 25th September 2014, 04:48 AM   #4
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If that's the fold, wouldn't there be some removable panels at the rear to gain access to the drivers?
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Old 25th September 2014, 04:58 AM   #5
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Quote:
Originally Posted by Brian Steele View Post
If that's the fold, wouldn't there be some removable panels at the rear to gain access to the drivers?
The access panels are in the top right and the bottom right. That's how we know where the drivers are. (You can see the access panels in the photos.)
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Old 25th September 2014, 11:20 AM   #6
Osse is offline Osse  Sweden
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I don't agree with the way he stack them(shallow and big surface) would be much cooler if he stacked them deep, laying down...
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Old 25th September 2014, 11:33 AM   #7
DrDyna is offline DrDyna  United States
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Quote:
Originally Posted by Osse View Post
I don't agree with the way he stack them(shallow and big surface) would be much cooler if he stacked them deep, laying down...
I wonder if the way they're stacked has any sort of the same effect as a slot load? It looks as though the "eye" opening is quite a bit smaller than the combined terminus.

In any event, I'm terribly jealous of the folks that get to work for DSL, it's never a boring day!
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Old 25th September 2014, 11:46 AM   #8
xrk971 is offline xrk971  United States
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I wonder if the Danley design is a plain bass horn or if it may be tapped? Basically the blue area for the bass horn rear chamber would be removed exposing the driver back to the flow. The path is still the same now if a TH, gains additional extension and efficiency. Did DSL post any measured freq responses?

Very rough estimate of bass extension is 3 x 1.5m=4.5m path. 342m/s / 4.5m / 4-wave=19Hz.

Last edited by xrk971; 25th September 2014 at 11:55 AM.
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Old 25th September 2014, 02:04 PM   #9
Osse is offline Osse  Sweden
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Quote:
Originally Posted by DrDyna View Post
I wonder if the way they're stacked has any sort of the same effect as a slot load? It looks as though the "eye" opening is quite a bit smaller than the combined terminus.

In any event, I'm terribly jealous of the folks that get to work for DSL, it's never a boring day!
If I understood you correctly, I somewhat agree with you. I'm not familiar with slot loading so I can't comment on that, but to my very limited knowledge I think, for being a FLH(what I think it is), the total mouth area in relation to the internal volume seem somewhat small. The general consensus afaik is that the mouth area in flh designs are in direct relation with generated spl, but his BC cabs are similar(compressing at mouth) but I just think it looks bad. And not as mean as 'conservatively' stacked FLH's.
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Old 25th September 2014, 02:25 PM   #10
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What gives it cardioid response?
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