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Re: T-48 best driver?

Posted: Thu Mar 25, 2021 5:28 pm
by singtall
I'm an Eminence dealer so I have access to all of their speakers. I've been mulling it over in my head which way to go.

to respond to an earlier response...Yes, I am aware that subwoofers stacked on either side of the stage creates a "power alley" and it isn't at all the "best" place to put subs. when possible on permanent installs like churches and clubs we always install subs in the center under the stage.

one of the main issues here is that we have been doing small club jobs more as of late and can't really put subs in the middle or take up much space. hence the thought of building front loaded smaller cabinets however inefficient they may be. I used a borrowed Peavey PA system with one 18", a 15" and horn per side with more than enough power and though it fit the place size-wise it surely lacked in db for this metal band. on another job I borrowed some Carvin TRX3218's (just one per side) and I have never heard so much great sounding low end from one cabinet before. That's the db level and portability that I'm after.

I looked for reviews on these horn loaded cabinets and couldn't find much besides people fighting over specs and calling this place a cult. lol. I'm still thinking....

Re: T-48 best driver?

Posted: Thu Mar 25, 2021 5:38 pm
by Bill Fitzmaurice
There's no need to cluster subs stage center. To either side is just as effective. To either side close to a wall is even better.

Re: T-48 best driver?

Posted: Thu Mar 25, 2021 5:59 pm
by Rich4349
Grant Bunter wrote: Tue Mar 23, 2021 2:58 am
...Otops12's can utilize a better more expensive compression driver, allowing a lower crossover point. DR's can't use that same CD until you get to the DR280...
This is weird- I could have sworn the DR250s could be built with a compression driver or piezo array. The sales page agrees with me:

"And if you prefer compression HF drivers the DR250 can be loaded with a pair of Eminence ASD1001 drivers on a wide dispersion vertical horn array..."

But my 2008 copy of the plans don't- no mention of any compression driver option.

Re: T-48 best driver?

Posted: Thu Mar 25, 2021 7:26 pm
by Seth
singtall wrote: Thu Mar 25, 2021 5:28 pm
Seth wrote: Mon Mar 22, 2021 9:05 pm
singtall wrote: Mon Mar 22, 2021 7:04 pm I'm also looking at things like total cabinet height with the top stacked on top of the sub.
I know you see this done all over the place and even big companies advertise systems set up this way... It sells products, but 95% of the time it's the worst location for a subwoofer. Better to put the subs where they work well and put the tops on tripods.

Here's a quick read that speaks to the subject; Rules for Subwoofer placement and stacking

...Yes, I am aware that subwoofers stacked on either side of the stage creates a "power alley" and it isn't at all the "best" place to put subs. when possible on permanent installs like churches and clubs we always install subs in the center under the stage.
It's not so much about avoiding power alley's and valley's. It's more about avoiding deep cancellations due to proximity to walls as well as taking advantage of the benefits of boundary loading. Every venue has it's challenges. Corner or wall loading isn't always an option. However, if it is an option, it would be a mistake not to take advantage of it. Even wall loaded way off to the side or corner loaded behind the stage will, more times than not, create a noticeably better result than one per side or clustered in front of the stage. Biggest thing would be to keep radiating plane of the subs closer than 2 feet or more than 8 feet from a wall.

There's some good info in that link. Might consider giving it a look-see.

Re: T-48 best driver?

Posted: Thu Mar 25, 2021 10:17 pm
by Seth
singtall wrote: Thu Mar 25, 2021 5:28 pm one of the main issues here is that we have been doing small club jobs more as of late and can't really put subs in the middle or take up much space. hence the thought of building front loaded smaller cabinets however inefficient they may be. I used a borrowed Peavey PA system with one 18", a 15" and horn per side with more than enough power and though it fit the place size-wise it surely lacked in db for this metal band. on another job I borrowed some Carvin TRX3218's (just one per side) and I have never heard so much great sounding low end from one cabinet before. That's the db level and portability that I'm after.
If size is of concern, you might be happier with T39's loaded with 3012LF's. A quartet of them corner or wall loaded would be overkill in a small club (not in a bad way). The biggest difference between the T39 and T48 is the T48 offers about 5hz deeper extension. Which, for a metal band, you'd never miss. Don't think a 12" can give you the volume you desire? I assure you, 4 of them would likely bitch slap the cabs you mentioned above, even at their narrowest cab build width. (wider T39/T48 cabs = louder & lower)

I looked for reviews on these horn loaded cabinets and couldn't find much besides people fighting over specs and calling this place a cult. lol. I'm still thinking....
Yeah, I was in your shoes once and I've seen them too. Most of those are 10+ years old, back when arguing on the internet was oddly popular. Here's what another guy who was also in the same thought process you're in had to say.

I wish I had the opportunity to silence the critics!

Re: T-48 best driver?

Posted: Fri Mar 26, 2021 3:58 am
by Grant Bunter
Rich4349 wrote: Thu Mar 25, 2021 5:59 pm
Grant Bunter wrote: Tue Mar 23, 2021 2:58 am
...Otops12's can utilize a better more expensive compression driver, allowing a lower crossover point. DR's can't use that same CD until you get to the DR280...
This is weird- I could have sworn the DR250s could be built with a compression driver or piezo array. The sales page agrees with me:

"And if you prefer compression HF drivers the DR250 can be loaded with a pair of Eminence ASD1001 drivers on a wide dispersion vertical horn array..."

But my 2008 copy of the plans don't- no mention of any compression driver option.

What you've written is true, the DR250 can be loaded with ASD's. But not NSD's or their most recent equivalent, and it's those that allow a 1. something k crossover. NSD's or their equivalent won't fit in a DR250...

Re: T-48 best driver?

Posted: Fri Mar 26, 2021 4:06 am
by Grant Bunter
Seth wrote: Thu Mar 25, 2021 7:26 pm
It's not so much about avoiding power alley's and valley's. It's more about avoiding deep cancellations due to proximity to walls (or lack of stack separation) as well as taking advantage of the benefits of boundary loading. Every venue has it's challenges. Corner or wall loading isn't always an option. However, if it is an option, it would be a mistake not to take advantage of it. Even wall loaded way off to the side or corner loaded behind the stage will, more times than not, create a noticeably better result than one per side or clustered in front of the stage. Biggest thing would be to keep radiating plane of the subs closer than 2 feet or more than 8 feet from a wall.
Kinda fixed that for you mate.

Stacks need to be separated by 2 wavelengths to not create cancellations.
At 40Hz, that's more than 51 feet, or 17 yards.
If you can't do that, raise the subs HP until cancellations aren't a problem.
If you have to raise the HP so much you're into kick drum territory, rethink your strategy...

Re: T-48 best driver?

Posted: Fri Mar 26, 2021 7:16 am
by Seth
Grant Bunter wrote: Fri Mar 26, 2021 4:06 am
Seth wrote: Thu Mar 25, 2021 7:26 pm
It's not so much about avoiding power alley's and valley's. It's more about avoiding deep cancellations due to proximity to walls (or lack of stack separation) as well as taking advantage of the benefits of boundary loading. Every venue has it's challenges. Corner or wall loading isn't always an option. However, if it is an option, it would be a mistake not to take advantage of it. Even wall loaded way off to the side or corner loaded behind the stage will, more times than not, create a noticeably better result than one per side or clustered in front of the stage. Biggest thing would be to keep radiating plane of the subs closer than 2 feet or more than 8 feet from a wall.
Kinda fixed that for you mate.

Stacks need to be separated by 2 wavelengths to not create cancellations.
At 40Hz, that's more than 51 feet, or 17 yards.
If you can't do that, raise the subs HP until cancellations aren't a problem.
If you have to raise the HP so much you're into kick drum territory, rethink your strategy...
Yup, that too. :thumbsup:

Cancellation zones skirt the power alleys, which I've heard referred to as "power valleys". Strong summation skirted by deep cancellations.

Image

Rule of thumb: Subs together and loaded into a wall or corner provides noticeable gains in output and avoids known cancellation/summation zones. Venue to venue, it's most likely to produce the best results... Even if it doesn't "look" right. Sure, there are venues that nothing seems to work or that splitting the subs my work to your advantage. Just gotta work with what ya got and be willing to try a few different configurations.

Re: T-48 best driver?

Posted: Fri Mar 26, 2021 11:21 am
by Rich4349
Do these rules for separation vs piling together apply to the same degree outdoors? I'm wondering about a small local outdoor venue with a ~4' permanent stage, maybe 30' wide. I'm wondering what would produce the best and safest result:
a 6' tall stack of 3 high x 2 wide 24" T-48s, v-plated and ratchet strapped together (and mounted to...???)
2x2 T-48s, same configuration, but with #5 and #6 Titans standing upright, in line and abutting the vplated quad, firing into the mouth, same direction, same vector of attack. (And can these 48-in tall Titans be used to extend the v plate even larger, out of most of a sheet of plywood? Their hornpath length would be a foot or two shorter than the primary four.)

Or, all 6 side by side, mouths at ground level, firing at the crowd.

Re: T-48 best driver?

Posted: Fri Mar 26, 2021 11:55 am
by Bill Fitzmaurice
They apply even more so outdoors. Indoors you have walls and ceilings that affect the result. Outdoors you don't. The Meyer Sound picture above is outdoors.

Re: T-48 best driver?

Posted: Sun Mar 28, 2021 6:37 pm
by singtall
thanks for all of the feedback guys. I spent some time the other night with WinISD working on a Carvin type speaker cabinet loaded with Eminence 18"s and couldn't come up with anything better than a 2-18" Carvin looking cabinet output 131DB with 1600watts RMS pushing it. not super efficient i would think. the speaker designs here are looking better and better.

I ran sound today in a large club that has three JBL 2-12" plus 2" horn tops with 4 JBL 2-18" bottoms and tons of power. hated it! the bottom end just sounded muddy and resonated loudly on one note. I didn't have a chance to eq the mains as we were the starting band, and never did the main sound guy. we both hated it. he tells me that he hates JBL subs with a passion. see where I'm going here? loud for the sake of loud ain't what I'm after. I'm really trying to put together something far more hi-fi sounding even though the band plays metal mostly.

I don't see myself needing more than a PA large enough to give me great sound at up to 110db if needed indoors for 200 people or less. anything like outdoor events I can just rent from a local sound company. so I'm looking at the T39 and T48 as a possible good way to go.

Re: T-48 best driver?

Posted: Sun Mar 28, 2021 6:59 pm
by singtall
so back to the original question: what is the BEST driver for the T-48? I'm an Eminence dealer so I can definitely get a better deal on them but if something else is better I'll go that way. thanks guys.

Re: T-48 best driver?

Posted: Sun Mar 28, 2021 7:50 pm
by Bruce Weldy
singtall wrote: Sun Mar 28, 2021 6:59 pm so back to the original question: what is the BEST driver for the T-48? I'm an Eminence dealer so I can definitely get a better deal on them but if something else is better I'll go that way. thanks guys.
The 3015LF is lighter and cheaper than any of the other options and it is considered one of the premium drivers. You can spend twice as much for a little more output, but you'd be better off to build twice as many boxes with the 3015LF - way more bang for the buck. It would be louder with the less power.

As far as JBL subs.....I've mixed on a single sub SRX8xx box all the way up to several JBL boxes per side under a line array to large crowds outdoors.....they are fine. System tuning is what it's all about. Whether JBL, Yamaha, QSC, powered and passive - I mixed on all of 'em. Don't really have a preference - they all put out all the low end I need to mix live music.

I like my BFM rig for output, size, price, and way more sound for less money and less power.

You won't be disappointed with either T39s or T48s loaded with the 3012LF or 3015LF drivers. They will definitely be cleaner sounding that direct radiators, but you might need more of them than you would with a 300 pound 2x18 driven with 4000 watts.

Re: T-48 best driver?

Posted: Sun Mar 28, 2021 8:43 pm
by singtall
Thanks for the reply Bruce. looks like I'm building 3015LF boxes...at least 4 of them. now to narrow down that perfect top.

Re: T-48 best driver?

Posted: Sun Mar 28, 2021 10:25 pm
by Bruce Weldy
singtall wrote: Sun Mar 28, 2021 8:43 pm Thanks for the reply Bruce. looks like I'm building 3015LF boxes...at least 4 of them. now to narrow down that perfect top.
I've never heard DRs, but I absolutely love the OTop12s with the 1.2k crossover option. They are great sounding boxes for vocals. But, if you go that way, build 4 - they sound better coupled....

Even if I do a show with only 2 subs, I still use all 4 tops....