BillFitzmaurice.info

CarterKraft wrote: ↑Thu Sep 02, 2021 9:57 am Does anyone have a video of a Omni12 playing by itself they could share?

I'll be dusting off my OT12's and T39's this weekend; but as Bill stated, without good recording equipment it'll be all in vain

Bill Fitzmaurice wrote: ↑Thu Sep 02, 2021 11:03 am A video is only as good as what it was recorded with and what it's listened to on. That's why I have SPL charts posted of the cabs and not videos. As for chuchero, most of what I see are primitive designs from guys who really, really don't have any understanding of even the basics of audio. Some aren't bad, but they're the exception.

I understand the recording-reproduction issue for sure, trying to convince a 17 year old boy of that is not as easy.
The main thing I am curious about is with a Omni12TB how much bass there will be compared to say a conventional bass reflex/ported 10" woofer, again out in the open space.
He wants to build the chuchero with a 10" front firing sub, I don't think he will get much output from it to make it worth while.
I would think the Omni with the 2x BP102 's would or the $$$ Kappa would be more actual bass output than a $50 car audio sub in a ported box.

jimbo7 wrote: ↑Thu Sep 02, 2021 6:23 pm

CarterKraft wrote: ↑Thu Sep 02, 2021 9:57 am Does anyone have a video of a Omni12 playing by itself they could share?

I'll be dusting off my OT12's and T39's this weekend; but as Bill stated, without good recording equipment it'll be all in vain

I'll take anything I can get at this point.
I would be interested to see with and without sub on some recorded music, with a heavy-ish bass line if I can be picky. And just one O12, 2 of them doesn't really fit the budget, space or concept we have in mind.

First off, jimbo7 has OT12s, not O12, meaning that they are tops only.

Here is a video of an non-TB O12. https://www.youtube.com/watch?v=N7VJH27HgSw

The bass reflex/ported 10" will not go as deep as a 2x12 O12, and, since the O12 is horn-loaded the O12 will be louder with equal power applied. The O12 will be a lot cleaner sounding, as well.

CarterKraft wrote: ↑Thu Sep 02, 2021 6:51 pm He wants to build the chuchero with a 10" front firing sub...

Compare the SPL charts of the chuchero to that of the O12.

To put it into context for a 17 year old who knows nothing about how loudspeakers work, consider choosing between two cars. One lists these specs:

ENGINE 2.0L/240-hp/255-lb-ft turbo DOHC 16-valve I-4
TRANSMISSION 8-speed automatic
CURB WEIGHT (F/R DIST) 3,498 lb (50/50%)
WHEELBASE 110.6 in
LENGTH x WIDTH x HEIGHT 182.2 x 71.3 x 56.3 in
0-60 MPH 5.4 sec
QUARTER MILE 14.1 sec @ 97.8 mph
BRAKING, 60-0 MPH 116 ft

The other doesn't list any specs. Which one would he buy? A known quantity or a pig in a poke?

A couple suggestions:

Build both, let him listen to them and decide what he thinks will impress his friends more. You're only out less than the price of a sheet of plywood, and you get to spend that much more quality / teaching time with your son. (This could be a double teachable moment: not just building techniques, but also critical thinking skills regarding design choice and research, performance vs appearance. Could help him with women in the future, too! lol)

Build the O12, lay it on its side (I know: comb filtering. At this point, though, I think soundwise a mis-oriented O12 will STILL be better than most of those churros whatevers), whip up a speaker grill frame covered with speaker mesh, and have an airbrush artist or silkscreener overlay the image of two subwoofers and tweeters on it.)

Bill Fitzmaurice wrote: ↑Fri Sep 03, 2021 7:04 am

CarterKraft wrote: ↑Thu Sep 02, 2021 6:51 pm He wants to build the chuchero with a 10" front firing sub...

Compare the SPL charts of the chuchero to that of the O12.

To put it into context for a 17 year old who knows nothing about how loudspeakers work, consider choosing between two cars. One lists these specs:

ENGINE 2.0L/240-hp/255-lb-ft turbo DOHC 16-valve I-4
TRANSMISSION 8-speed automatic
CURB WEIGHT (F/R DIST) 3,498 lb (50/50%)
WHEELBASE 110.6 in
LENGTH x WIDTH x HEIGHT 182.2 x 71.3 x 56.3 in
0-60 MPH 5.4 sec
QUARTER MILE 14.1 sec @ 97.8 mph
BRAKING, 60-0 MPH 116 ft

The other doesn't list any specs. Which one would he buy? A known quantity or a pig in a poke?

Excellent idea, because I can actually do that (not using the car audio brands) using the SPL charts from the commercial 12" bass cabs.
This alone will show the output comparatively of the two box designs with the same drivers.

I won a BP102-4 off ebay Saturday in sort of a panic not sure what I could use it for, It was cheap enough for me to gamble and so it is mine under $40.

I want to build a Omni 12TB or Jack12Lite.

I think I could use it in the Omni12TB with a matching pair or I could build a JAck110Lite but I think it is not the correct impedance for that cabinet.
It may not be the correct impedance for any BFM cabinet as far as I know.

What's the hive mind say?
Remember these cab's either/any design will be DC battery powered with Class D amps and portability and output as the major requirements followed by SQ.

edit: If all else fails I guess I can use it in a T24 or other sub.

Quote: I won a BP102-4 off ebay
If you could get a second one, then you could series-wire them for an 8 ohm load, and push up to 400w through them (for O12TB).

Nice speaker, but it's heavy enough to negate the benefits of Bill's "Lite" enclosures, IMO.
If you (for example) built a Jack 10 out of pine or spruce ply, you probably wouldn't notice much of a difference in weight compared to a "Lite" version built from Baltic birch. I have a pine version of the Jack 10 with an older non-approved driver. It sounds very good, a little light on the bass outdoors or away from a wall.

I have an OT12 as well, it's pretty big, With two non-neo 10 inch speakers it would be pretty heavy as well, but would sound huge.

I might consider a Simplex 10 made from one of the lighter plywoods. I have one, they sound really good.

You will have to consider your crossover. I think looking at the specs of the BP104-4 you could get away with the version of the filters in Bill's plans meant for two 8 Ohm speakers in parallel. But you should check with someone more knowledgeable. Some "4 Ohm" versions of popular speakers are not even close to half the impedence of their 8 Ohm versions, so you can't assume.

These are my thoughts as well, I really wanted a NEO driver for the Lite variants, even for the Omni to keep the weight down.

I think if this woofer will work for one of the subs that will be the better use of it.

I also picked up an inexpensive BP102 (not -4 though), open box deal on Amazon for about the same price. Was just a impulse buy when I saw the deal. If I ever get around to putting it in something, it'll probably be either a Max width T39 for band rehearsals or T45 for the garage system/party PA.

The BP102-4 will be great in a sub.
T24, T39, T45 are all candidates.
You will also be surprised how loud it can get with it's voltage limit.
As has already been stated though, you would want to wire it in series, not parallel, for one amp channel, if you added another...

Seth wrote: ↑Tue Sep 14, 2021 11:34 pm I also picked up an inexpensive BP102 (not -4 though), open box deal on Amazon for about the same price. Was just a impulse buy when I saw the deal. If I ever get around to putting it in something, it'll probably be either a Max width T39 for band rehearsals or T45 for the garage system/party PA.

This is how these things start
For recorded music (mostly Country) alone no live stuff would your pick be the T45?

Grant Bunter wrote: ↑Wed Sep 15, 2021 2:15 am The BP102-4 will be great in a sub.
T24, T39, T45 are all candidates.
You will also be surprised how loud it can get with it's voltage limit.
As has already been stated though, you would want to wire it in series, not parallel, for one amp channel, if you added another...

Thanks for the suggestions on cabs.
Can I ask you the same question as Seth,
For recorded music (mostly Country) alone no live stuff would your pick be the T45?