passive speaker amp matching

Lisa Lane-Collins

Sophomore
Dec 9, 2012
270
0
16
Adelaide, Australia
I kinda mostly almost have my head around this (amp should be rated halfway between the rms and peak capacity or something to that effect, and you can supply a more powerful amp, but without system protection, users might blow up the speakers right?) I don't feel confident enough with my knowledge to send this amp and speaker combo out without first asking advice and or asking, is there a way to measure the precise output of the amp?

The speakers and amp in question are a pair of EV SX300s and a Behringer inuke3000. So, speakers are 300w continuous, 1200 peak at 8 ohms. The local hire house sends them out with amps that are 500w a side....which is probably pretty much spot on. I don't have any amps at that rating though, just these goofy inukes. I haven't a clue what their true power output is because Behringer has not obliged to provide accurate information. I found a post online from someone who tested them and seem to recall that post saying they put out about 700 a side at 8 ohms....I'm gonna assume the limiting is useless and that the client will milk them for all they have.... I do have a compressor I can use to limit the rig if I need it, but being able to measure output (before, after) would make the process a whole lot more physics and less guess and hope.
 
Re: passive speaker amp matching

IIRC Behringer rate the inuke using their peak power. Assuming this, your amp is around 225W@8ohm cont. That is about 1.2 dB below their maximum rated cont power. AKA it will make sound, but there is some more potential left in it.

Assuming the clip limiters are decent, this speaker/amp combo should withstand some abuse, but it's not bulletproof IMHO.
(On a personal note, i think those speakers sound terrible, so write a good contract and have someone blow them up. Charge them for the damage done and use the money to invest in some new speakers)
 
Re: passive speaker amp matching

There is no exact easy answer.

I would argue that the "correct" answer lies somewhere between 1/2 continuous (or less) and peak power.

This is around a 10dB range-which is HUGE.

There are many many variables involved-type of music-alignment done-operator skill and so forth.

However for a "generally safe" answer-I suggest somewhere between continuous and twice continuous. But that does not guarantee you will not damage the loudspeaker.

Limiters can help-but are simply a measure of protection. Just like air bags. They can help keep you same in case of an accident-but if you drive your car off a cliff-don't expect the air bags to save you------------------
 
Re: passive speaker amp matching

Limiters can help-but are simply a measure of protection. Just like air bags. They can help keep you same in case of an accident-but if you drive your car off a cliff-don't expect the air bags to save you------------------

Nice, Do you have all of these analogies written down, or do you think of them as you go?
 
Re: passive speaker amp matching

Nice, Do you have all of these analogies written down, or do you think of them as you go?

That is why there should be an air bag on the outside of the car,
and an amp built into your speakers.

find out the drivers in your box, find a company using those drivers in their active boxes, and add 20%. Then Don't Panic, and always have a towel.
 
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Re: passive speaker amp matching

Lol

further data, they're intended for foldback, probably just vocals


Hi Lisa,

Best I can determine – continuous power

8 Ohm per channel, stereo 300 W
4 Ohm per channel, stereo 600 W
2 Ohm per channel, stereo 1000 W


Maximum / dynamic power output
8 Ohm per channel, stereo 440 W
4 Ohm per channel, stereo 880 W
2 Ohm per channel, stereo 1500 W


http://www.behringer.com/assets/NU1000_NU3000_NU6000_NU12000_NU1000DSP_NU3000DSP_NU6000DSP_NU12000DSP_WebBrochure.pdf

http://www.diyaudio.com/forums/class-d/213071-behringer-inuke-nu3000-measurements.html

Peter

 
passive speaker amp matching

(On a personal note, i think those speakers sound terrible, so write a good contract and have someone blow them up. Charge them for the damage done and use the money to invest in some new speakers)[/QUOTE]


I completely disagree on this one! And so do many people out there. These are probably the most popular speakers and probably the best in their price range! They have proved their ground and that's why they are still in production several decades down the road.
I personally own 18 of them and they have made me a small fortune!

Conrad
www.kooleventug.com

Sent from my iPhone
 
Re: passive speaker amp matching

Biggest problem I had with them was the quirk of being narrow throw (where all the rooms I'm in are long and wide), and of course tinny as, probably work a lot better with subs. Have a pleasant kind of clarity to them though, not that I've gotten to use them much at all (because of not being confident with the amp matching.

Wow the honest specs on the inukes show them to be a low powered amp indeed (lucky they were very cheap and I wasn't buying them for that ridiculous 1500 watts claim).

I have a PhonicXP3000 too, would that be a better match? https://phonic.app.boxcn.net/shared/ctmttkgo27 (looking at the specs I'd be leaning towards nope, too much juice..)
 
Re: passive speaker amp matching

I have a few NU-6000 and NU4-6000 4 channel that is just 2 3000's in one box. They normally power a 12" and 1.4" box that I have made with JBL drivers like your EV SX300. I biamp them but I find the iNukes has more than enough gas to run them well. I think you will be fine with the NU3000 running them unless you are doing heavy metal.
 
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Re: passive speaker amp matching

They are quite very efficient speakers. I have run mine a few occasions on a peavey xr amp mixer with 150 watts at 4r with great results. Wouldn't run them for serious stuff without subs though. Am sure the Nu3000 will be ample power.
Conrad


Sent from my iPhone