Hello. I'm Dave.

Message
Author
Gregory East
Posts: 3496
Joined: Sat May 13, 2006 9:56 pm

Re: Hello. I'm Dave.

#16 Post by Gregory East »



4 slims: Add 6dB to the dual chart rough enough, add a conservative 20dB for 1000W of power, add 12dB if you can corner load, add 3 dB for v-plate,

50hz @ 95+6+20+12+3 = 136dB 1m/1000W

I don't even know if that's possible.
BAT10, Bad Auto Tuba. Reverse folded TAT to fit JBL 1014D, 350W driver, voltage limit unknown.

dave_clancey
Posts: 26
Joined: Sun May 13, 2012 6:38 pm

Re: Hello. I'm Dave.

#17 Post by dave_clancey »

Brilliant, Mr. East! I'm up for amp recommendations, it would seem.

User avatar
doncolga
Posts: 1967
Joined: Thu Jul 01, 2010 3:01 pm
Location: Statesboro, GA
Contact:

Re: Hello. I'm Dave.

#18 Post by doncolga »

If you're using Eminence 3012 lf or Lab 12, those can go to 50 volts max, so an amp that will do that or more.

I believe the formula is Volts =SquareRoot(Watts * Ohms)

I try to not exceed 40 volts to my boxes but I have them limited at about 47 volts. I did a 4000 sq ft room last weekend for a birthday/ballroom dancing event with just my two bigger T30's and didn't go over 15 volts and up to about 112 dB C weighted on the dance floor, so I had plenty of headroom. I had them V plated and wall loaded. Very consistent coverage through the room. Had the room been bigger and I'd had more time, I probably would have used all four.

I've done Rooms A and B here a couple timse with just the two 18's wall loaded.

http://www.marriott.com/hotels/event-pl ... iverfront/

Another tip: If you're using Lab12's you may want to consider installing the reducer panels as soon as the inner chamber is put together. Things are a little easier to access that way. Later is certainly doable however. That's how I did mine.

My 18's are really easy to move with a hand truck for tip and roll and for stairs. I also keep a caster board under them and roll on that when it's flat all the way.
Donny Collins
Built:
Two 18" Tuba 30's 3012 LF
Two 26" Tuba 30's Lab 12
Two OmniTop 12's DL 2512 (Melded Array)
Presonus Studio One DAW
Harrison Consoles MixBus 32C DAW

dave_clancey
Posts: 26
Joined: Sun May 13, 2012 6:38 pm

Re: Hello. I'm Dave.

#19 Post by dave_clancey »

Great info, Donny. Seems like 4 will handle the room, and will run along nicely with a moderate amp. How far from the dance floor was the wall and your v-plated pair?

User avatar
doncolga
Posts: 1967
Joined: Thu Jul 01, 2010 3:01 pm
Location: Statesboro, GA
Contact:

Re: Hello. I'm Dave.

#20 Post by doncolga »

dave_clancey wrote:Great info, Donny. Seems like 4 will handle the room, and will run along nicely with a moderate amp. How far from the dance floor was the wall and your v-plated pair?
For the most recent the center of the dance floor was maybe 20 feet away. For the T18s in the bigger room the wall was probably 30 feet away from the center of the dance floor.
Donny Collins
Built:
Two 18" Tuba 30's 3012 LF
Two 26" Tuba 30's Lab 12
Two OmniTop 12's DL 2512 (Melded Array)
Presonus Studio One DAW
Harrison Consoles MixBus 32C DAW

dave_clancey
Posts: 26
Joined: Sun May 13, 2012 6:38 pm

Re: Hello. I'm Dave.

#21 Post by dave_clancey »

Built four at 16". Wondering what the *actual* impedance of the cab is. The amp will provide at 2ohms - the engineer fellow at Crown says the 2ohm rating is real, stable and reliable. Can I run all 4, and confidently, achieve 2 ohms or better?

Bruce Weldy
Posts: 8301
Joined: Fri Nov 27, 2009 11:37 am
Location: New Braunfels, TX

Re: Hello. I'm Dave.

#22 Post by Bruce Weldy »

dave_clancey wrote:Built four at 16". Wondering what the *actual* impedance of the cab is. The amp will provide at 2ohms - the engineer fellow at Crown says the 2ohm rating is real, stable and reliable. Can I run all 4, and confidently, achieve 2 ohms or better?

Which amp do you have? 4 labs one one side will take a pretty powerful amp to run at 50 volts.....

Why not run 2 per side?

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."

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

Re: Hello. I'm Dave.

#23 Post by Tom Smit »

dave_clancey wrote:Built four at 16". Wondering what the *actual* impedance of the cab is. The amp will provide at 2ohms - the engineer fellow at Crown says the 2ohm rating is real, stable and reliable. Can I run all 4, and confidently, achieve 2 ohms or better?
IITP
Bruce Weldy wrote:

Which amp do you have? 4 labs one one side will take a pretty powerful amp to run at 50 volts.....

Why not run 2 per side?
+1
TomS

Gregory East
Posts: 3496
Joined: Sat May 13, 2006 9:56 pm

Re: Hello. I'm Dave.

#24 Post by Gregory East »

Bruce Weldy wrote:
dave_clancey wrote:Built four at 16". Wondering what the *actual* impedance of the cab is. The amp will provide at 2ohms - the engineer fellow at Crown says the 2ohm rating is real, stable and reliable. Can I run all 4, and confidently, achieve 2 ohms or better?

Which amp do you have? 4 labs one one side will take a pretty powerful amp to run at 50 volts.....

Why not run 2 per side?
A smaller amp running cool, running forever, I'd choose that over a pricey amp giving its all.
BAT10, Bad Auto Tuba. Reverse folded TAT to fit JBL 1014D, 350W driver, voltage limit unknown.

dave_clancey
Posts: 26
Joined: Sun May 13, 2012 6:38 pm

Re: Hello. I'm Dave.

#25 Post by dave_clancey »

Thanks. This one is an XLS1500.

Bruce Weldy
Posts: 8301
Joined: Fri Nov 27, 2009 11:37 am
Location: New Braunfels, TX

Re: Hello. I'm Dave.

#26 Post by Bruce Weldy »

dave_clancey wrote:Thanks. This one is an XLS1500.

Not nearly enough to run 4 on one side....

Two a side is marginal at 50 volts.....but doable, just no real headroom.

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."

dave_clancey
Posts: 26
Joined: Sun May 13, 2012 6:38 pm

Re: Hello. I'm Dave.

#27 Post by dave_clancey »

I have a pair. Would bridged mono be sufficient for 2, you suppose?

Bruce Weldy
Posts: 8301
Joined: Fri Nov 27, 2009 11:37 am
Location: New Braunfels, TX

Re: Hello. I'm Dave.

#28 Post by Bruce Weldy »

dave_clancey wrote:I have a pair. Would bridged mono be sufficient for 2, you suppose?
I run an XLS1500 bridged to power two T39s with 3012LFs limited to 56 volts with a fair amount to headroom.

The 1500 just doesn't have enough juice to run your subs to full output of 50 volts running one per channel or two per channel. I would bridge both amps and run two off each. You must use a limiter as you'll have more than enough power and don't want to smoke the drivers.

The other option would be to sell the two 1500s and go to an XTI4000. Personally, I'd keep 'em as I already know that it works well.

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."

dave_clancey
Posts: 26
Joined: Sun May 13, 2012 6:38 pm

Re: Hello. I'm Dave.

#29 Post by dave_clancey »

Thanks. 'Did just that through a Driverack and they really do have quite a bit to offer, now. On with the hunt for a gorgeous amp for my tops. need a 1200/2400 peak rms at 8 ohm. Not an inexpensive proposition, I'm afraid. Thanks to all you fellows who chimed in. They really are quite nice. I think they'll do just fine.

Bruce Weldy
Posts: 8301
Joined: Fri Nov 27, 2009 11:37 am
Location: New Braunfels, TX

Re: Hello. I'm Dave.

#30 Post by Bruce Weldy »

dave_clancey wrote: need a 1200/2400 peak rms at 8 ohm.
wow....what are you running for tops?

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."

Post Reply