Piezo tweeter x-over question

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himhimself
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Location: Bloomington IN

Piezo tweeter x-over question

#1 Post by himhimself » Mon Sep 03, 2018 10:49 am

In the plans, it says if the array sounds overly bright, place the 4 ohm resistor between the jack connection and the 5.6uF capacitor, which will reduce the array sensitivity. For those of you who have Otops with the 1016s, did you require this mod? If yes, any details? Melded vs. straight? Slightly different component specs?
I tend to not like super bright high end. I'm planning to build two melded, two straight. Was thinking perhaps to tone down the melded array this way, and use the standard x-over setup for the straight, as they will be aimed higher. All the cabs will get the same signal from the driverack, so no ability to EQ differently.
Or am I overthinking this too early?
Am cutting 32 horn braces right now and needed a little break...
2xT30 (20", 3012lf)
4xOtop Jarray

Grant Bunter
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Location: Ilfracombe Queensland Australia
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Re: Piezo tweeter x-over question

#2 Post by Grant Bunter » Mon Sep 03, 2018 3:35 pm

You're kinda overthinking this to early.
I don't have Otops, I built DR250's, which have a larger melded array, and asked the same question at build time.

You need to try it as per the plans first me thinks. The array does settle down after some use. The flat array will be bright as well, so you could EQ all 4 to taste.
EQ is a better way to deal with the "issue"...
Built:
DR 250: x 2 (melded array) with March 2012 plans. 2 more under way with CD horn
T39's: 4 x 20" BP102 , 2 x 28" 3012lf.
WH8: x 3 with melded array.
Bunter's Audio and Lighting "like"s would be most appreciated...

Bruce Weldy
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Re: Piezo tweeter x-over question

#3 Post by Bruce Weldy » Mon Sep 03, 2018 4:00 pm

If you are using a premium driver, the woofer should keep up with the Piezos just fine. I think the bad balance would come from using less sensitive woofers that would make the Piezos louder by comparison.

My OTops with the arrays are loaded with 2512s and it's not a problem at all......build 'em, then if you can't fix any issues with EQ, add the part to the crossover.

6 - T39 4-25" 2-22" 3012LF
4 - OT12 2512 Melded/NSD2005
1 - T24
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."

himhimself
Posts: 276
Joined: Fri Nov 13, 2015 9:34 pm
Location: Bloomington IN

Re: Piezo tweeter x-over question

#4 Post by himhimself » Mon Sep 03, 2018 4:14 pm

Thanks guys. Was curious if I'd get a, "Whoa, definitely do the mod cuz they're too bright"...seems not necessarily the case, so I will build per the plans and see what happens. I am just using the basic Beta drivers, not the premiums, so that may make a difference, but sensitivity seems pretty much the same. At least in per the spec sheets.
2xT30 (20", 3012lf)
4xOtop Jarray

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Bill Fitzmaurice
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Re: Piezo tweeter x-over question

#5 Post by Bill Fitzmaurice » Mon Sep 03, 2018 4:19 pm

Spec sheet sensitivity numbers do not reflect the cab, so they're not really useful. The Beta 12 isn't as sensitive as the 3012HO, but it's sufficient.

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Tom Smit
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Location: Sarnia, Ont. Canada

Re: Piezo tweeter x-over question

#6 Post by Tom Smit » Mon Sep 03, 2018 11:08 pm

Make sure that you still use the 4 ohm resistor as shown in the plans.
TomS

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