matching speakers
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Posted on Jun 09, 2010 09:59 am
rayss
Member Since: Mar 04, 2009
lets say i buy one 12" main pa speaker but want to use two, later when i am ready to buy or find one for sale but can't find one exactly like the one i have how will i know its ok to buy a different speaker and use it together out of the same powered mixer, either in daisy chaining if it only has one out or i wanna use the other out for another two or using one out to each speaker.
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Jun 09, 2010 02:31 pm You have to know all of the specs of your original boxes, and try to match those specs the best that you can.
Specs to know are:
Power handling
Pattern shape of the horn
SPL, or dB of the box
Frequency response
Ohm load
Many manufactures keep the same specs in a different shape or style of boxes. Just look for the specs that best matches yours.
rayssMember
Since: Mar 04, 2009
Jun 09, 2010 04:31 pm whats the harm if i do not do a good job of matching specs, can it damage the speakers, can it damage the powered mixer?
thaks for your help.
Jun 09, 2010 04:34 pm The wrong resistance (ohms) can damage the amp...which sucks.
rayssMember
Since: Mar 04, 2009
Jun 10, 2010 02:32 pm so lets say i do make sure to match the ohms will i be ok if the watts dont match, lets say i have one that says 400 rms and then get one with same ohms but says 250 rms.
also what if the speaker its self is different size, one 12 and one 15 but same ohms can i safeley run them from the same powered mixer?
thanks again.
Jun 11, 2010 05:37 pm Dude your killing me.....
If you have different speakers....... Then don't you think that they are not going to sound the same?
They are going to sound different right?
The answer is RIGHT!!! The boxes are not going to sound the same if you mix and match speakers together.
A 12" will sound different from a 15" box. So why on Earth would you want to put them on the same side?
I think that these are all of the boxes that you have access to. And your looking for someone to tell you "Yes! Go ahead, it will be fine!" Sorry Rayss. I am not going to tell you that.
Mixing speakers together on a self powered mixer is just asking for trouble.
pjkPrince CZAR-mingMember
Since: Apr 08, 2004
Jun 13, 2010 10:23 am here's my take:
an output has parameters: the OHMS it wants to see to be happy, and the max wattage that it can safely put out.
speakers have their nominal impedance, in OHMS, and the max wattage that it can handle, but also their efficiency and their basic sonic performance.
So,
you can have an output, that has rated impedance of 8 ohms, and a max wattage (on the amp) of say 500w.
So this means that if you plug in 1 speaker of 8 ohms, rated for 250w, then you possibly could overdrive / blow the speaker, but the amp is happy with it's reflected impedance : 8 ohm.
Conversely, if you had an 8 ohm speaker, rated at 700w, then you shouldn't be able to blow that speaker with that particular amp (though I wouldn't push it).
Now, if you have 2 speakers, you have to add up (or calculate) the impedance:
8 ohm in series with 8 ohm = 16 ohm
8 ohm in parallel with 8 ohm = 4 ohm
4 ohm in series with 8 ohm = 12 ohm
4 ohm in parallel with 8 ohm = 2.6 ohm
So you can see there's things to consider considering speaker reflected impedances and amps requirements.
Here's a nifty page that lets you know alot about speakers, amps, and why you should learn their parameters and proper operation:
www.bcae1.com/spkrmlti.htm
Now, say you have (2) 16 ohm speakers, running in parallel, for 8 ohms. One speaker efficiency is 85db, the other is 95db. This means that you'll only hear speaker 2, since it's way more efficient. In this fashion, you can't depend on what power handling you're capable of, because of the mismatch of efficiencies.
The size isn't going to affect the operational parameters, you can run a 12 and 15 together, provided the impedance and wattage are running properly.
Rob, i think budget is driving these questions, as I've been there before, trying to make things run with what i have, sometimes in the free department.
For wattage, if (1) speaker can handle 500w, and another can handle 250w, then you can run them together, as long as operational parameters are decent. The higher W speaker will sound slightly different, but most speakers do, as Rob stated above.
Also, you can run a small power amp into a high power speaker without problem, again, as long as the impedance is OK. But don't try and push 1000w into a 150w speaker and turn it up. Smoke and gnashing of teeth will follow.
rayssMember
Since: Mar 04, 2009
Jun 22, 2010 09:46 am thanks a lot, yeah i am not so much looking for quality as i am for safety, since it is a case of working with what i got, quality will come later, i just dont wanna blow a speaker or powered mixer.
thanks a bunch for the info.
