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Pabloaguas wrote: ↑Mon Jan 25, 2021 5:26 pm I think the B&G is the clear winner with almost double the force factor (bl) of the lab12... should translate to tighter bass, right?

Wrong. Forget about whatever you know about direct radiator speakers, it doesn't apply to horns. As for 'tight bass', that''s a meaningless term. It's typically used by laymen who don't know the actual engineering term for whatever it is that they're trying to describe. It's not as illogical as 'fast bass', but it's no more useful either.

Pabloaguas wrote: ↑Mon Jan 25, 2021 5:26 pm

Seth wrote: ↑Mon Jan 25, 2021 4:42 pm To clarify a little on what Grant and I have said...

Volume, to a listener is somewhat subjective. But, it's fairly standard to reference an increase of 10dB (measured) as twice the perceived volume/output. However, doubling the Vd of a driver is measured as 3dB. So, while 33% more displacement does equate 33% more measured output... measured, it would only equate to about 1dB, when it takes 10dB to be perceived as twice as loud.

So, as perceived by the listener, that additional 33% displacement only means a increase in volume that is just barely perceptible.

Got it!

I think the B&G is the clear winner with almost double the force factor (bl) of the lab12... should translate to tighter bass, right?

So what about the limiting on my amp... sufficient for voltage protection?

Whether or not the BL difference will equate to anything noticeable or measurable in a real world horn application is outside my wheelhouse. My guess is it wouldn't make it any worse. Seems it should be beneficial though.

Like Bruce and Grant said, you're going to want a true peak limiter that wont allow the amplifiers output voltage to ever go above 50v. It's the right way to get the job done and not have to worry about blown drivers in the middle of a performance. Could you get away without? Perhaps. Up to you if you want to gamble your money and reputation on blown drivers or not.

Ultimately, the standard response here is that a driverack, DCX2496, or similar processor with a true "Brick Wall" peak limiter is mandatory gear for horn loaded subs.

Bruce Weldy wrote: ↑Mon Jan 25, 2021 5:39 pm

Pabloaguas wrote: ↑Mon Jan 25, 2021 4:26 pm
Grant, do you think that the "clip limiter" built into my QSC RMX 2450 would be a sufficient voltage limiter?

No, no, a thousand times no.....

There are a few amps that have true limiters in them - that one doesn't. You'll need a real limiter that you'll set with a voltmeter. The best option is a driverack. Don't try to use an old stand alone limiter as it can be changed with a knob on the front - not safe.

Any recommendations for amps that have one built in?

Bill Fitzmaurice wrote: ↑Mon Jan 25, 2021 6:13 pm

Pabloaguas wrote: ↑Mon Jan 25, 2021 5:26 pm I think the B&G is the clear winner with almost double the force factor (bl) of the lab12... should translate to tighter bass, right?

Wrong. Forget about whatever you know about direct radiator speakers, it doesn't apply to horns. As for 'tight bass', that''s a meaningless term. It's typically used by laymen who don't know the actual engineering term for whatever it is that they're trying to describe. It's not as illogical as 'fast bass', but it's no more useful either.

Tight bass comes from proper placement and EQ......fast bass comes from attaching a chain to the sub and dragging it behind your pickup....

Pabloaguas wrote: ↑Mon Jan 25, 2021 6:22 pm

Bruce Weldy wrote: ↑Mon Jan 25, 2021 5:39 pm

Pabloaguas wrote: ↑Mon Jan 25, 2021 4:26 pm
Grant, do you think that the "clip limiter" built into my QSC RMX 2450 would be a sufficient voltage limiter?

No, no, a thousand times no.....

There are a few amps that have true limiters in them - that one doesn't. You'll need a real limiter that you'll set with a voltmeter. The best option is a driverack. Don't try to use an old stand alone limiter as it can be changed with a knob on the front - not safe.

Any recommendations for amps that have one built in?

You have to get into much higher end amps......if you already have amps, it's much cheaper to add a driverack to your system.....you get crossover, EQ, limiting, and anti-feedback all in one unit.....and if you place it at the top of your rack, you don't have to try and stand on your head to make adjustments to the amp on the bottom of the rack.

Seth wrote: ↑Mon Jan 25, 2021 6:21 pm Whether or not the BL difference will equate to anything noticeable or measurable in a real world horn application is outside my wheelhouse.

BL and Qes go hand in hand. Higher BL/Lower Qes typically results in higher midrange sensitivity in direct radiators. That's also true to some extent in horns, but no so much as with direct radiators. Never forget that with a direct radiator 75% of the result is due to the driver, with a horn 75% of the result is due to the enclosure.

Bill Fitzmaurice wrote: ↑Mon Jan 25, 2021 6:30 pm

Seth wrote: ↑Mon Jan 25, 2021 6:21 pm Whether or not the BL difference will equate to anything noticeable or measurable in a real world horn application is outside my wheelhouse.

BL and Qes go hand in hand. Higher BL/Lower Qes typically results in higher midrange sensitivity in direct radiators. That's also true to some extent in horns, but no so much as with direct radiators. Never forget that with a direct radiator 75% of the result is due to the driver, with a horn 75% of the result is due to the enclosure.

Thanks for that little tid-bit of enlightenment. Makes sense that it wouldn't be as big of a factor on the low end, since every octave lower and lower the motor structure has twice the time to move the cone mass.

Bruce Weldy wrote: ↑Mon Jan 25, 2021 5:39 pm

Pabloaguas wrote: ↑Mon Jan 25, 2021 4:26 pm
Grant, do you think that the "clip limiter" built into my QSC RMX 2450 would be a sufficient voltage limiter?

No, no, a thousand times no.....

There are a few amps that have true limiters in them - that one doesn't. You'll need a real limiter that you'll set with a voltmeter. The best option is a driverack. Don't try to use an old stand alone limiter as it can be changed with a knob on the front - not safe.

Bruce- what about the RDL ST-CL2... I can just stick it in my amp for convenience, and no one could touch the settings once i set it up. The mfr claims instantaneous limiting. Spec sheet link:

https://www.rdlnet.com/downloads/datasheets/st-cl2.pdf

Pabloaguas wrote: ↑Mon Jan 25, 2021 6:22 pm

Bruce Weldy wrote: ↑Mon Jan 25, 2021 5:39 pm

Pabloaguas wrote: ↑Mon Jan 25, 2021 4:26 pm
Grant, do you think that the "clip limiter" built into my QSC RMX 2450 would be a sufficient voltage limiter?

No, no, a thousand times no.....

There are a few amps that have true limiters in them - that one doesn't. You'll need a real limiter that you'll set with a voltmeter. The best option is a driverack. Don't try to use an old stand alone limiter as it can be changed with a knob on the front - not safe.

Any recommendations for amps that have one built in?

I belive the Crown Xti series has a suitable limiter.

Pabloaguas wrote: ↑Tue Jan 26, 2021 3:55 pm

Bruce Weldy wrote: ↑Mon Jan 25, 2021 5:39 pm

Pabloaguas wrote: ↑Mon Jan 25, 2021 4:26 pm
Grant, do you think that the "clip limiter" built into my QSC RMX 2450 would be a sufficient voltage limiter?

No, no, a thousand times no.....

There are a few amps that have true limiters in them - that one doesn't. You'll need a real limiter that you'll set with a voltmeter. The best option is a driverack. Don't try to use an old stand alone limiter as it can be changed with a knob on the front - not safe.

Bruce- what about the RDL ST-CL2... I can just stick it in my amp for convenience, and no one could touch the settings once i set it up. The mfr claims instantaneous limiting. Spec sheet link:

https://www.rdlnet.com/downloads/datasheets/st-cl2.pdf

Absolutely not. That is some kind of averaging compression unit....something you'd use in a paging system. Get a driverack. Used ones can be found for $200-300 all day long on CL or eBay. The PA, PA+, PX, or PA2 will do the job.

whines wrote: ↑Tue Jan 26, 2021 4:37 pm I belive the Crown Xti series has a suitable limiter.

My old Xti 2002 does not have that capability. The new ones say there's a limiter, but very little information in the manual about how to use it. I'd have to actually look at one to see if it would do the proper limiting. In that past, Crown has marketed the Peak Plus limiting - but that just protected the amp from overloading - it wasn't a voltage limiter at all.

I like Crown (have 6 or 7 of 'em), but their manuals suck.

Bruce Weldy wrote: ↑Tue Jan 26, 2021 5:47 pm

whines wrote: ↑Tue Jan 26, 2021 4:37 pm I belive the Crown Xti series has a suitable limiter.

My old Xti 2002 does not have that capability. The new ones say there's a limiter, but very little information in the manual about how to use it. I'd have to actually look at one to see if it would do the proper limiting. In that past, Crown has marketed the Peak Plus limiting - but that just protected the amp from overloading - it wasn't a voltage limiter at all.

I like Crown (have 6 or 7 of 'em), but their manuals suck.

I remember someone else having questions about the Xti series and looking into that with you a little while ago and really liking the PC app and Graphic User Interface, "Band Manager". From what I recall, I wanna say it did have an appropriate peak limiter.

Just downloaded the app again and looking at it's limiter options, it should be suitable. Attack can be set as low as 0.01s and the limit can be set as either dBFS or voltage, which is handy. Looks to me like it's a valid option. But, I too would like to have one in my hands with a meter on it to verify before pointing people in that direction. Or, at least have a conversation with one of their techs about it. I do love the interface though. Darn cool.

What about getting a used DBX 166 and putting in a locked box?

Pabloaguas wrote: ↑Tue Jan 26, 2021 7:31 pm What about getting a used DBX 166 and putting in a locked box?

Again, no.

The limiter on the older style compressor(s) is meant to be used for dynamic limiting only, not constant monitoring, and as such isn't brick wall. It can be set that way, but then you don't get EQ, crossover's with various types and steepness of slope, as well as delay, RTA and automated feedback control that you get with the driverack series, all in 1 rack unit.

Go with the driverack. Ultimately it is better value than the DCX2496 which has everything the driverack has, except RTA, GEQ and feedback control, which are obtained by pairing the DCX with a DEQ 2496, which makes the pair = 2RU in height...

ok, I finally got it. Get the drive rack. Thanks everyone for being patient with me. They have the driverack pa2 for $250 at ProAudioStar. (hopefully it survives shipping from them lol)