Finally! Omni 12 Tall Boy build

High power and fidelity from an easy to build cabinet.
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CarterKraft
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Finally! Omni 12 Tall Boy build

#1 Post by CarterKraft »

I finally got the funds gathered up to build one of the full range PA style cabinets.

I got some 3012HO drivers coming from Bills clearance rack. One will go in a Jack for portable Bluetooth speaker duty and the other in this Omni 12 Tall Boy.

I plan on the O12TB being portable, battery powered as well.

The build should be straight forward but the amp, battery, etc. are still up in the air.
I can get amps in many flavors to do this at pretty much any power level.

The easiest and lowest $ solution is the Taramps MD 250x1 4 ohm. It's rated at 160w @ 8 ohms.
It works with my battery options and is cheapish at $99.

So the question I have to ask you guys is 160w going to be adequate to excersize these drivers in a outdoor venue? If I need more watts is not a problem but I don't want to do this twice if you know what I mean...
Weldon Carter

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Seth
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Re: Finally! Omni 12 Tall Boy build

#2 Post by Seth »

CarterKraft wrote: Thu Aug 25, 2022 7:07 pm So the question I have to ask you guys is 160w going to be adequate to excersize these drivers in a outdoor venue?
To put that into perspective, if you ran twice the power you'd only get 3dB more and burn through the battery twice as fast.

It'll be good. If you need more output, you need more cabs.

Personally, I'd be looking at some of the board amps on Parts-Express that have built in DSP. Might not jive with your intended battery source though.
Build in process - 2 WH6, one Alpha 6a loaded, one PRV Audio 6MB250-NDY loaded

Two 2x6 shorty SLA Pro's
One T39, 16", 3012LF loaded
Tall AutoTuba, 20" wide, 2x 8" MCM 55-2421
TruckTuba, 8½" wide, 2x 8" MCM 55-2421

CarterKraft
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Location: DFW

Re: Finally! Omni 12 Tall Boy build

#3 Post by CarterKraft »

Seth wrote: Fri Aug 26, 2022 7:51 am
CarterKraft wrote: Thu Aug 25, 2022 7:07 pm So the question I have to ask you guys is 160w going to be adequate to excersize these drivers in a outdoor venue?
To put that into perspective, if you ran twice the power you'd only get 3dB more and burn through the battery twice as fast.

Point taken but 4+ times the power is only $100 more.... obviously I don't have to run it that hard but I will have the ability.

It'll be good. If you need more output, you need more cabs.

That is a possibility but the second cab will likely be a 3012HO equipped jack12L.
This a portable only build. I will likely have a port to charge/run off wall power but it can't be part of the design. This is the volleyball, river etc. pop up party boom box.


Personally, I'd be looking at some of the board amps on Parts-Express that have built in DSP. Might not jive with your intended battery source though.

There are many choices of board amps. I originally had my sights set on them but as you (I think) pointed out they are rated a very low ohm loads and might not produce much power at 8 ohms. I had wanted DSP with bi-amping but the board amps require wildly varying DC voltages that are problematic for off the shelf (lightweight, high density) battery options. I can still do DSP in the bluetooth module for bi-amping but I wonder how worth it is?
To recap the goals from my previous thread.
Hopefully compete with the direct radiating DiamondBoxx XL2 https://diamondboxx.com/collections/all ... oducts/xl2
xl2.jpg
Be "portable" I intend to integrate the wheels to the cabinet to make it easier to haul, handles etc.
Weldon Carter

CarterKraft
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Re: Finally! Omni 12 Tall Boy build

#4 Post by CarterKraft »

Two amps I found that would fit my higher voltage battery source (Ryobi 40v battery) is the TPA3255 based amp.

There are two variants, a 300wx300w and a 600w mono.
At 8 ohms the X2 300w version makes 150w per channel.
The mono version does 300w mono.

I can DSP the output of the bluetooth module or use a bluetooth module with integrated DSP.
I will use a TWS (true wireless stereo) and APTx reciever to allow the cabinet to share its signal with the JAck or other cabinet for more output.
Weldon Carter

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Bill Fitzmaurice
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Re: Finally! Omni 12 Tall Boy build

#5 Post by Bill Fitzmaurice »

Batteries are like electric chairs: it's not the voltage that counts, it's the amperes. Multiply the volts x amperes to find out how much power a battery can actually deliver.

CarterKraft
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Re: Finally! Omni 12 Tall Boy build

#6 Post by CarterKraft »

The 12 volt battery I would like to use can deliver 15 amps continuous.
The 40v battery can deliver 60 amps continuous.

The problem with the board amps is the voltage requirements are all over the place, varying from symetrical AC supplies to DC voltage from 12-48v.

Building a dedicated battery at the required voltage is not a problem but I would like to avoid it and utilize the available power tool batteries of platforms I already own.
Milwaukee M12, M18
Ryobi 18+ and 40v.
Weldon Carter

CarterKraft
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Re: Finally! Omni 12 Tall Boy build

#7 Post by CarterKraft »

Bill Fitzmaurice wrote: Fri Aug 26, 2022 11:34 am Batteries are like electric chairs: it's not the voltage that counts, it's the amperes. Multiply the volts x amperes to find out how much power a battery can actually deliver.
IS there a driver voltage limit for this woofer in this cab?
Basically the question is how much power (watts) is the maximum?
Weldon Carter

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Seth
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Re: Finally! Omni 12 Tall Boy build

#8 Post by Seth »

CarterKraft wrote: Fri Aug 26, 2022 9:05 am I can still do DSP in the bluetooth module for bi-amping but I wonder how worth it is?
Even if you didn't bi-amp, DSP would still be an invaluable tool to be able to EQ and shape the sound the cab produces to be the most satisfying it possibly can be. I know some of those DSP modules also have the capability of processing psycho-acoustic bass enhancements, which could be handy in a battery powered portable deal by relieving the need to produce the actual frequencies that typically consume a lot of power and replacing them with harmonics of the low frequencies that fool our minds into thinking it's hearing the actual bottom notes. I've been itching to do something like this too, either in a WH10 or Jack10 Lite. I'll be following along closely and am anxious to witness your project unfold, whatever direction it takes!
Build in process - 2 WH6, one Alpha 6a loaded, one PRV Audio 6MB250-NDY loaded

Two 2x6 shorty SLA Pro's
One T39, 16", 3012LF loaded
Tall AutoTuba, 20" wide, 2x 8" MCM 55-2421
TruckTuba, 8½" wide, 2x 8" MCM 55-2421

CarterKraft
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Location: DFW

Re: Finally! Omni 12 Tall Boy build

#9 Post by CarterKraft »

I will try to incorporate DSP, it shouldn't be hard or cost prohibitive, I originally wanted it anyway...

I need to get a feel for watts/db of this thing so I might just build it and use my shop PA amps and measure voltages.

If I go multi channel DSP, would I need any hardware crossover components?
Weldon Carter

Bruce Weldy
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Re: Finally! Omni 12 Tall Boy build

#10 Post by Bruce Weldy »

CarterKraft wrote: Fri Aug 26, 2022 3:11 pm

If I go multi channel DSP, would I need any hardware crossover components?
That cab is three way, so unless the DSP can do a 3 way crossover, you'll need to build the crossovers. That would be the smart way to go anyway. Otherwise you'll need multiple amps. Put in the passive crossovers and use a mono amp setup....

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."

CarterKraft
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Re: Finally! Omni 12 Tall Boy build

#11 Post by CarterKraft »

Bruce Weldy wrote: Fri Aug 26, 2022 3:17 pm
CarterKraft wrote: Fri Aug 26, 2022 3:11 pm

If I go multi channel DSP, would I need any hardware crossover components?
That cab is three way, so unless the DSP can do a 3 way crossover, you'll need to build the crossovers. That would be the smart way to go anyway. Otherwise you'll need multiple amps. Put in the passive crossovers and use a mono amp setup....

I can do 4 channel DSP pretty easily and multiple amps/channels isn't really a problem either.
Worth it is another thing all together.

I trust your guys opinions but also realize we want to try new stuff now and again.
I want to try DSP and maybe this is the cab but maybe not, the Jack would be allot easier to DSP and or bi-amp though so maybe that is where I spend that effort.

Do you have a "ideal" watts for this cab Bruce?
Weldon Carter

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Seth
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Re: Finally! Omni 12 Tall Boy build

#12 Post by Seth »

As far as I am aware, the full range and mid/High tops are limited more by audible distortion than they are the driver ratings or driver displacement. In the past, Bruce has mentioned that he recalled Bill mentioning something to the effect of limiting to half the drivers RMS value. However, I'm fairly certain this isn't an absolute and is more of a rule of thumb. I can attest that my SLA's play clean enough to not be objectionable all the way up to their RMS based voltage of 56, high passed at 125Hz. They are very very mildly distorted at that point, but not enough that any reasonable patron would notice. To really know for sure, I think you'll have to hook them up to some power, EQ them to taste, and find out firsthand. But, even then, I'm not sure how you'd go about discerning where the limit is. I guess measure voltage at the frequency you have most boosted in EQ when distortion arises and aim to put an amp in it that's capable of roughly the same output??? I don't really know. That's the only thing that makes sense at the moment. Hmmm.
Build in process - 2 WH6, one Alpha 6a loaded, one PRV Audio 6MB250-NDY loaded

Two 2x6 shorty SLA Pro's
One T39, 16", 3012LF loaded
Tall AutoTuba, 20" wide, 2x 8" MCM 55-2421
TruckTuba, 8½" wide, 2x 8" MCM 55-2421

CarterKraft
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Location: DFW

Re: Finally! Omni 12 Tall Boy build

#13 Post by CarterKraft »

That's fair I realize I'm asking for info that might not be available.

The hard part of this deal is obviously going to be the power, amplifier and Bluetooth.
I just want enough power to make it worth it...
There is a Dayton KAB that looks good, dsp and all but they don't have TWS for pairing to another cabinet.

I might go with it anyway because I can use it in the old blast box if it doesn't work best here, the amp in the blast box is pretty cheap.

I will go forward and get the cabinet built.
Weldon Carter

CarterKraft
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Re: Finally! Omni 12 Tall Boy build

#14 Post by CarterKraft »

This is the Dayton amp with DSP and 4x100 watts.
It will run fine off my 40v batteries and should have enough juice with two of the channels bridged.

It really seems perfect, has all the peripheral options I need, it should make a really polished product.

https://www.parts-express.com/Dayton-Au ... SP-325-434

Specifications
Power output (w/ 36 VDC power supply): 4 x 100W @ 6 ohms
SNR: 97 dB 2 x 50W @ 8 ohm, THD+N=1%, 26 dB, A-weighting
THD+N: 0.07% 10W @ 6 ohm 1 kHz 26 dB
Frequency response: 20 to 20,000 Hz (±3 dB)
Impedance: 4-8 ohms
Recommended power supply: 36 VDC, 5-10A
Working Voltage: 10 to 39 VDC
Board mounting holes center to center spacing: 4.1" x 3.2" (111.76 x 81.28 mm)
Hole diameter: 0.15" (3.8 mm)
Dimensions: 4.8" L x 3.6" W x 1.5" H
Weldon Carter

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Seth
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Re: Finally! Omni 12 Tall Boy build

#15 Post by Seth »

Did you see this review on the info/sales page?
https://billfitzmaurice.info/Omni12.html wrote:I've used my pole mounted Omni 12s several times so far (both with and without T24s) as the mains for my brother-in-law's 4 piece cover band and have received raves for clarity vs. his JBL Eon G2s. Easily able to be louder than you'd want to listen to with just a QSC RMX850 (185 watts) pushing them.
At least that puts a number on the board for consideration.
Build in process - 2 WH6, one Alpha 6a loaded, one PRV Audio 6MB250-NDY loaded

Two 2x6 shorty SLA Pro's
One T39, 16", 3012LF loaded
Tall AutoTuba, 20" wide, 2x 8" MCM 55-2421
TruckTuba, 8½" wide, 2x 8" MCM 55-2421

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