Finally! Omni 12 Tall Boy build

High power and fidelity from an easy to build cabinet.
Message
Author
CarterKraft
Posts: 255
Joined: Thu Oct 22, 2020 1:46 pm
Location: DFW

Re: Finally! Omni 12 Tall Boy build

#136 Post by CarterKraft »

Sounds good Bruce thank you.

That is about where I had it in the shop the other night.
I am interested to see the results because inside I had a decent dip around 2250 that I couldn't get up no matter what. A outside test will be required though as my workshop is FILLED with large reflective objects.
Weldon Carter

User avatar
Seth
Posts: 2731
Joined: Thu Sep 10, 2009 8:06 pm
Location: Sacramento, California, USA
Contact:

Re: Finally! Omni 12 Tall Boy build

#137 Post by Seth »

CarterKraft wrote: Wed Oct 05, 2022 7:39 am Final detail question.
Optimism is a good thing. :lol:

I agree with Bruce. Since your going to want the test signal 10-20dB (20dB is better if it's not too loud) above the highest point of the noise floor in the frequency range you're testing, the further out you go, the louder it will need to be (+3dB for every doubling of distance). Mic at a height roughly on axis with the mid and tweeter, 5-10 feet should be great.

It's not uber important. But, since were taking the time to do it, may as well take a moment, consider the environment, and be mindful and deliberate about choosing the best possible placement to minimize reflections.

In your test video, I don't know if you heard the reflection off your neighbors house at the end of the driveway. It's far enough away that it's not likely to affect your measurement. But, a quick glance of the space, I think I'd set it up, maybe not exactly, but somewhere around here, aimed toward the X. Or, depending what's behind that tree line (anything reflective?), maybe in that corner with the X aimed out toward the circle, 45º to most of the reflective surfaces in the area (buildings, vehicles, etc.).
Screenshot (212).png
Not a huge deal breaker. But, just a reminder to be mindful and intentional when you choose your placement.


I have a small request. More video please. Next time, longer duration and horizontal.
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

User avatar
Seth
Posts: 2731
Joined: Thu Sep 10, 2009 8:06 pm
Location: Sacramento, California, USA
Contact:

Re: Finally! Omni 12 Tall Boy build

#138 Post by Seth »

CarterKraft wrote: Wed Oct 05, 2022 9:29 am I am interested to see the results because inside I had a decent dip around 2250 that I couldn't get up no matter what.
Yeah, when a dip doesn't respond to EQ, most likely causes are inter driver phase cancellation or reflective cancellation from the environment. A lot of times, if you change the microphone location or speaker orientation a little bit, it will clear up... or move to a different frequency. If it's a frequency near the crossover point and it doesn't change with different mic location, more than likely a phase issue or an environmental cancellation from not testing high enough above the noise floor. Same goes for response peaks, or any frequency, no matter it's measured level, that doesn't respond predictably to EQ.
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
Posts: 255
Joined: Thu Oct 22, 2020 1:46 pm
Location: DFW

Re: Finally! Omni 12 Tall Boy build

#139 Post by CarterKraft »

I was thinking something like you suggested Seth, possibly rotated more towards the South but in that corner is fine for me, it is open for a long way behind that tree line.

I will take more video for sure, the videos were taken by my son who has a totally different video style than myself.

This is a satellite view to help with some scale. I have plenty of schools with large open parking lots but I am not sure if I can get a better/lower noise floor at them. I will set up here and give it a run, if I run into problems I'll find a new location.

sound test.JPG
Weldon Carter

CarterKraft
Posts: 255
Joined: Thu Oct 22, 2020 1:46 pm
Location: DFW

Re: Finally! Omni 12 Tall Boy build

#140 Post by CarterKraft »

I had some time this evening for a test run.
Ran outside to find the only thing ill be eq-ing is a few Cicadas... Not a great noise floor.

So I messed with the battery power supply.
I got a 1200w "china rating" boost converter to use the Milwaukee or Ryobi 18v batteries. I set it to 35.75 volts and tested it for a hour at easy listening volume.

It didn't get above ambient temperature and battery voltage was still 20v when I went inside on a 5ah battery.
It's hard to say on run time yet but with up to 12ah batteries off the shelf the desired runtime is there.
20221006_212949.jpg
20221006_212954.jpg
20221006_213339.jpg
Weldon Carter

User avatar
Seth
Posts: 2731
Joined: Thu Sep 10, 2009 8:06 pm
Location: Sacramento, California, USA
Contact:

Re: Finally! Omni 12 Tall Boy build

#141 Post by Seth »

CarterKraft wrote: Thu Oct 06, 2022 10:07 pm ...Ran outside to find the only thing ill be eq-ing is a few Cicadas...
:lol:
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
Posts: 255
Joined: Thu Oct 22, 2020 1:46 pm
Location: DFW

Re: Finally! Omni 12 Tall Boy build

#142 Post by CarterKraft »

Life got in the way...

Never got the sound check done but I demoed the "dB Slayer" as is over Thanksgiving, did a war volume salute with " God Bless America" that blew some minds in the off-road park we stayed at.

Lost my Dad December 5th, he was 67 and a hell of a man and father, that has slowed me down but time in the shop helps.

I stripped it down last weekend and got it in flat black waiting on the Duratex to get here.

I am wanting to do a painted logo on the front, anyone have any experience with that on Duratex?
I can make the stencil with my vinyl cutter just curious how it will adhere to the texture of the Duratex.
dB Slayer badge.JPG
Weldon Carter

User avatar
Tom Smit
Posts: 7457
Joined: Sat Jan 05, 2008 1:24 pm
Location: Sarnia, Ont. Canada

Re: Finally! Omni 12 Tall Boy build

#143 Post by Tom Smit »

Weldon, sorry to hear about your father.

I think that there might be some difficulty getting defined paint lines on the Duratex since Duratex ends up something like an orange peel. Perhaps, if you taped off an area, where you would like the emblem, and keep that area free from Duratex, then, it may work out fine.
TomS

CarterKraft
Posts: 255
Joined: Thu Oct 22, 2020 1:46 pm
Location: DFW

Re: Finally! Omni 12 Tall Boy build

#144 Post by CarterKraft »

Thank you Tom.

That was my concern too. I might try to cut some foam to make the stencil out of then just duratex over it and pull the foam.put of the duratex after it starts to set up.

I probably need to test this all out but I hate paint so much we'll see if I have the stomach for it.
I also liked the 3D printed BF logo in the tips sub forum.
I might get my brother to 3D print me something.
Weldon Carter

User avatar
Seth
Posts: 2731
Joined: Thu Sep 10, 2009 8:06 pm
Location: Sacramento, California, USA
Contact:

Re: Finally! Omni 12 Tall Boy build

#145 Post by Seth »

A quick googling turned this up...
AVS Forum, can you paint over duratex
yes you can paint over it, just sand it with some 120 to rough it up and go to town. I've done it myself.
I'd add to that, that many other posts recommended making sure it's 100% completely cured before doing so. While the Duratex Application Guide says it's fully cured in 1-3 hours and is dry to the touch, I've personally found (and read of others saying) that it takes at least a week (likely more) at room temperature for DuraTex to fully harden. Or, less than a day in elevated temperature. Next time I DuraTex something, If I don't have nice, hot, direct sunlight available, I think I'll create a little curing oven with a cardboard box and a space heater... see how that does. Based on what I've read over the years 100-120ºF (38-49º) should do. However, that's completely speculation based on recollection of some random internet babble. Don't take it as any sort of factoid. Oops.. got to rambling there. That's all I got. I look forward to hearing of your experience with the process :thumbsup:
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
Posts: 255
Joined: Thu Oct 22, 2020 1:46 pm
Location: DFW

Re: Finally! Omni 12 Tall Boy build

#146 Post by CarterKraft »

No worries, rambling is what I do best haha.

I have a plan to crank my AC in my shop to dehumidify and run a 250w heat lamp rotating side to side to get it dried. The heat lamp seems to do a great job in safely putting heat into a object with little risk to unattended fire etc.

What does the hive mind think about putting this battery/holder in the mouth of the port? Obviously it will change the port volume, but does it matter enough at this far edge of the flare? I can install it and test but before making holes I wanted to get a idea of the consensus.
20230104_071121.jpg
20230104_071021.jpg
Weldon Carter

jimbo7
Posts: 849
Joined: Fri Dec 28, 2012 10:45 am
Location: St. Louis

Re: Finally! Omni 12 Tall Boy build

#147 Post by jimbo7 »

Why not have your brother 3d print a battery holder clip thingy and mount it on the back? Like this: https://www.thingiverse.com/thing:4850997
BFM builds:
XF212
T24 BP102 24"
2x SLA's 6-5" mids, 9- gt-302's
2x AT 14" MCM 55-2421
TrT 5" MCM 55-2421
AT 18" JBL GTO804
2x OT12 flat array
2x SLA Pro 2-Alpha 6's 2-Goldwoods
2x T39 24" 3012lf
Simplex 10 BP102

CarterKraft
Posts: 255
Joined: Thu Oct 22, 2020 1:46 pm
Location: DFW

Re: Finally! Omni 12 Tall Boy build

#148 Post by CarterKraft »

I have one of the injection molded holders for it.
I don't want anything protruding from the sides, front or back for the sake of easy loading/unloading and not to prevent accidental damage to the box or transporter.

Top is the first seed but I thought it could get hidden in the port that's a two birds deal.
Weldon Carter

User avatar
Seth
Posts: 2731
Joined: Thu Sep 10, 2009 8:06 pm
Location: Sacramento, California, USA
Contact:

Re: Finally! Omni 12 Tall Boy build

#149 Post by Seth »

I like that location. Clean and handy spot. Just a guess, but I don't think it'll hurt anything enough to rule it out.
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

User avatar
Seth
Posts: 2731
Joined: Thu Sep 10, 2009 8:06 pm
Location: Sacramento, California, USA
Contact:

Re: Finally! Omni 12 Tall Boy build

#150 Post by Seth »

Also... I was thinking about the dB logo. What if you painted the color of choice on the cab prior to DuraTex, put the stencil on, DuraTex over the stencil, then peel it up before the DuraTex dries. Might look pretty cool that way.
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

Post Reply