FOH Engineer
Lunatic Member
- Please expand I put my reply in the wrong place.
That is because they are better built than hifi stuff. "Pro gear" (more precisely: PA gear) is designed to drive multiple speakers at very high volume for long time periods; these units are therefore very stable and capable of delivering high currents, which is key.
Less impedance (you can't talk of "resistance" with loudspeakers) = more current demand at same voltage. This is where home hifi units fail; most of them just cannot provide the current (see above as well). Therefore, most of them actually will give more power at four ohms compared to eight, but they will break down at two.
What do you mean by "doubling"? Double the rated input power of the speakers?
IMHO, it is key to have an amp whose power rating exceeds the rated input power of the speakers by a margin. Not necessarily because of headroom (headroom is amp-internal only anway), but because of distortions: a transistor amp, driven at its limits, will emit loads of high-order distortions that are infamous for killing tweeters. Since weak amps get to the clipping point earlier, they are actually more "dangerous" to speakers than big ones (if you crank them up that is).
@avionic: no need to grab popcorn; we're all nice here. [/QUOT
The basic principles are all the same whether its hi fi or pro gear etc. Assuming you enjoy high volume listening, a larger than needed amp wont damage a speaker with square wave clipping like an underpowered amp driven into clipping will..
Amps are rated for various loads for instance 100 watts at 16 ohms 200 watts at 8 ohms 400 at 4 and perhaps 1000 in bridged mono...the resistance of the speaker determines what the amp will do..or in some cases some amps have switchable configurations...if you use two 8 ohm speakers on one channel you are presenting the amp with a 4 ohm load on that channel...I do not mean this as anything other than a lighthearted fun disscusion and you seem like a good guy
Please understand my intent..
I dont think of this as my opinion it is fact and its called Ohms law...
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