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Old 6th October 2012, 02:58 AM   #21
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I think you will find that the delta 12 has just too low a mass corner, to give enough output in that horn.
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Old 6th October 2012, 01:26 PM   #22
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i have limited knowledge regarding speaker parameters but do understand enough to know theyre pretty critical, could you explain what, or why a low mass corner is and why its good/bad?
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Old 6th October 2012, 11:18 PM   #23
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The mass corner is defined as 2fs/Qt, above this the power output starts to roll off at 6db. per octave when horn loaded.

For your drivers this occurs at too low a frequency.

There are midbass drivers especially made for horn loading, that have mass corners in the 750Hz. region and rising frequency response above this, these can go flat to a few kHz.
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Old 7th October 2012, 10:23 PM   #24
col is offline col  Australia
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One option would be to re-box your Delta 12's and add another pair. I recently built 4 of the Eighteen Sound trap boxes with P.Audio WN12"s and a Selenium D-2500Ti with a "econowave" style passive crossover. The results are very good.

Click the image to open in full size.

Running a pair each side gives a wide coverage as the boxes bunch up better.

Eighteen Sound Kits

They are very easy to make as long as you have a means to do angle cuts.

Edit: just realised, there is a "econowave" style crossover for the Delta 12 with a Selenium D220 and the clone JBL PT waveguide (Dayton Dayton Audio H6512) on our photo gallery:

Click the image to open in full size.

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Last edited by col; 7th October 2012 at 10:38 PM.
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Old 7th October 2012, 11:44 PM   #25
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sorry i havent been active in this convo, i had been away for the weekend.


col, just wondering, would i get better out put from one cab with 2x12 drivers, or two cabs each with 1x12 ???

i was at at wedding and noticed the DJ had only one 15 inch active cab. it sounded nice at lower levels and got loud enough on its own to have a good dancing session.

regarding what drivers to use for mid/tops, if i was to bother with buying more deltas, would i be better off upsizing instead? running something like the HD15 cabs off the speakerplans forum just for outright kick/punch ? it would certainly take a load off the deltas.

right this minute, im first going to get an active XO. after having some discussion via PM, i think its imperative i get one of those first. then the next step is more drivers, as my amps arent maxing out yet, i still have room to breathe there. it was also suggested to get DSP/compressors too. so as at this point i have zero knowledge about those, ill best be doing some research.
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Old 8th October 2012, 10:30 PM   #26
col is offline col  Australia
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I don't think it will make much difference to max output if you run 2 x 12" drivers or two cabs with 1x12". The good thing though, is that it keeps the system more modular and flexible for different configurations, for example with a 4in x 8out xover if you need or want you can run your rig in quadraphonic. Some electronic music producers working with Ableton Live are increasingly using this "quad panning" now.

Using 15"s in mid-high requires exceptionally good 1" or 2" comp drivers as the cone break up on the 15" happens at a lower frequency so usually you have to cross out of them sooner. Most 15" top boxes Iv'e heard have sounded terrible in comparison to a good 12", when used with a sub (not stand-alone). There are some exceptions but usually very expensive 15"s like the powered QSC or powered JBLs.
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Old 9th October 2012, 01:54 AM   #27
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you just gave me confirmation, kinda, in a round-a-bout way, i think what ill do, is ill keep my deltas as they are. they truly sound fantastic im not complaining about that.

what ill do, ill definately get myself an active XO. that i think will be the beginning of the path to true epic.

after that, the next speaker upgrade i think will be a quad of HD15 cabs. keeping it all modular.

i think doing it like that will keep me the opportunity to use just my deltas, or, deltas and HD15, or delta, HD215 and SS15 combos for any sized gigs. or, as you said, Modular.

any suggestions or opinion on that?
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Old 10th October 2012, 01:25 PM   #28
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Guys thanks for all the input. Ive been playing with hornresp and discovered that my delta specs are wrong. So i fixed that and also went looking for hd15 and lascala HR specs. And without uploading response graphs coz my internet is capped i ran comparisons through sealed then reflex then HD15 then Lascala. And out of the four, my reflex sims the quietest of all. Folled by sealed then hd15 with the LS being the loudest. The hd15 gives bass down to about 85-90hz where the LS drops off at about 110-120 but with an active XO i think the LS cabs are definately the way to go for replacing my reflex cabs as full range. And also could add a third component in there in the form of a pair of 3" drivers for high mid frequencies.

Im pretty excited to get the ball rolling on this before nye. But first things first will be an active XO for sure.
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Old 10th October 2012, 09:42 PM   #29
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The best acoustic power output in the non horn loaded boxes is given by the QB5 II alignments.

This is the way to get the most bass from the least space, and if you are carting speaker boxes around this allows the maximum sound in the smallest volume, i.e. you can use a smaller vehicle.
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Old 11th October 2012, 04:05 AM   #30
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Pack space isnt an issue atm. So regarding outroght max volume i think the sims frpm HR speak for them.selves.

Ill upload as soon as my internet is uncapped.
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