Why you can't use Folded horn with direct radiating.

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Armchair Pirate
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Joined: Wed Jun 29, 2011 11:53 am

Why you can't use Folded horn with direct radiating.

#1 Post by Armchair Pirate »

People hire me to come out and supplement their sound, I end up completely bypassing their system and running my own. Problem is I know you DO NOT use folded horn tubas with anything other then more folded horn tubas. Fortunately once the tubas are on, all questions cease, unfortunately until then. I don't know how to explain WHY you don't run direct and tubas together.


:feedback:
Built so far
4x Duel Lab 12 T60 30"

Next
2x DR280
2x D12 T60

Bruce Weldy
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Re: Why you can't use Folded horn with direct radiating.

#2 Post by Bruce Weldy »

I'll take a non-technical stab at it...


The signal reaches the speakers at the same time, yet the folded horn's sound takes 7-9 feet to get out of the cabinet, while the direct radiator is instant. The difference in length alone can create phase issues.

I'm sure there are many more reasons, but's that's what I'd tell 'em. They could understand that.

6 - T39 3012LF
4 - OT12 2512
1 - T24
1 - SLA Pro
2 - XF210


"A system with a few knobs set up by someone who knows what they are doing is always better than one with a lot of knobs set up by someone who doesn't."

sine143
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Location: Raleigh NC

Re: Why you can't use Folded horn with direct radiating.

#3 Post by sine143 »

You can also say that those issues are not as easily fixed as just delaying the direct radiators to "match" the t60, as it has its own unique phase characteristics.
Built:
2x Tuba 30s delta12lf loaded (gone)
4x Otop12 d2512 loaded
8x t48s (18, 18, 24, 24, 30, 30) 3015lf loaded
2x AT (1 mcm, 1 gto 804)
2x SLA Pro (dayton pa6, 6 goldwood piezo loaded)
1x bastard XF208

2x OT212 (delta pro 450a loaded, eminence psd)

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SoundInMotionDJ
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Re: Why you can't use Folded horn with direct radiating.

#4 Post by SoundInMotionDJ »

Armchair Pirate wrote:I don't know how to explain WHY you don't run direct and tubas together.
This caution is not specific to folded horns.

The caution exists in ANY situation when the SAME signal is sent into DIFFERENT cabinets. The cabinets will have a different response, with different dispersion patterns in the space. Getting reasonable integration between those different responses requires independent EQ on each cabinet type at a minimum...and may require more than that, depending on the details. The intrinsic delay of the horn path is another complication that must be accounted for.
10 T39S + 10 DR200 + 1 T48

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Bill Fitzmaurice
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Re: Why you can't use Folded horn with direct radiating.

#5 Post by Bill Fitzmaurice »

Armchair Pirate wrote: I don't know how to explain WHY you don't run direct and tubas together.
Phase response. Since they won't even know what phase response is they should be sufficiently impressed that you do and leave it at that.
Or you could just say that their tinker toy subs suck and shouldn't even be in the same room with yours. :lol:

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J_Dunavin
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Re: Why you can't use Folded horn with direct radiating.

#6 Post by J_Dunavin »

:lol:
2 - OTop8
2 - T39
8 - DR200
2 - DR250
9 - T24
6 - T45
1 - Auto Tuba

MissileCrisis
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Location: Walnut Creek, California

Re: Why you can't use Folded horn with direct radiating.

#7 Post by MissileCrisis »

+1 to the tinker toy sub comment. I'm fairly sure nothing I've seen people use around here remotely touches the capabilities of my BFM cabs. I know for sure that my T60 is > my 2 15 inch direct radiator subs (albeit non-Pro subs) in output disregarding the distortion issue.
Built
2 x TLAH
1 Titan 39 (lab 12, 15 inch)
1 Tuba 60 (lab 12, 20 inch)
SLA Center
2 x Mini MLTP subwoofers
1 x 212 TH (custom)
2 x Mini-Karlsonators
Owned, but not built
2 x Jack 12 (2512, melded)

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escapemcp
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Re: Why you can't use Folded horn with direct radiating.

#8 Post by escapemcp »

SoundInMotionDJ wrote:This caution is not specific to folded horns.

The caution exists in ANY situation when the SAME signal is sent into DIFFERENT cabinets. The cabinets will have a different response, with different dispersion patterns in the space. Getting reasonable integration between those different responses requires independent EQ on each cabinet type at a minimum...and may require more than that, depending on the details. The intrinsic delay of the horn path is another complication that must be accounted for.
So how do we get away with melded arrays for a bottom cab and compression drivers for the top? Can someone explain this as I was mulling over this very question this afternoon whilst duratexing! Thanks :)

sine143
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Re: Why you can't use Folded horn with direct radiating.

#9 Post by sine143 »

remember, you can use seperate cab types, etc when they are more than 2 wavelengths apart. in the hi frequency band, this becomes a very small distance. Hi frequency is also VERY directional, (esp in the vertical plane with these cabs) so there is very little crossover between the soundwaves. Someone bouncing on a trampoline is likely to hear some combing though.
Built:
2x Tuba 30s delta12lf loaded (gone)
4x Otop12 d2512 loaded
8x t48s (18, 18, 24, 24, 30, 30) 3015lf loaded
2x AT (1 mcm, 1 gto 804)
2x SLA Pro (dayton pa6, 6 goldwood piezo loaded)
1x bastard XF208

2x OT212 (delta pro 450a loaded, eminence psd)

Grant Bunter
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Re: Why you can't use Folded horn with direct radiating.

#10 Post by Grant Bunter »

escapemcp wrote:
SoundInMotionDJ wrote:This caution is not specific to folded horns.

The caution exists in ANY situation when the SAME signal is sent into DIFFERENT cabinets. The cabinets will have a different response, with different dispersion patterns in the space. Getting reasonable integration between those different responses requires independent EQ on each cabinet type at a minimum...and may require more than that, depending on the details. The intrinsic delay of the horn path is another complication that must be accounted for.
So how do we get away with melded arrays for a bottom cab and compression drivers for the top? Can someone explain this as I was mulling over this very question this afternoon whilst duratexing! Thanks :)
sine's response is good.
I'll add to it as well.
When you have a melded array in one cab and a CD in another, it's only the HF section that is different right?
The mid driver and horn path in both cabs is otherwise identical.
Yes, there is some time difference between the two HF sections you mentioned, plus the third, or flat array. The HF in all three sections leaves the cab at different times.
In order, flat would be first, slightly before the melded (which has it's elements sitting back slightly further) then the CD horn.

Enough people here biamp, and that allows to also time delay HF compared to mids, so you can have the sound leaving the cabs at the same time, and further, adjust different HF as well...
Built:
DR 250: x 2 melded array, 2x CD horn, March 2012 plans.
T39's: 4 x 20" KL3010LF , 2 x 28" 3012LF.
WH8: x 6 with melded array wired series/parallel.
Bunter's Audio and Lighting "like"s would be most appreciated...

Armchair Pirate
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Joined: Wed Jun 29, 2011 11:53 am

Re: Why you can't use Folded horn with direct radiating.

#11 Post by Armchair Pirate »

:loler: HAHAHAHAHAHA to the tinker toy comment. Thank you for all your feedback.
Built so far
4x Duel Lab 12 T60 30"

Next
2x DR280
2x D12 T60

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