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Audio Systems/how power amplifier work ?


1 - if poweramplifier give 1120 watts at 8 ohms then it give higher
output at 6 ohm ?
2 - if poweramplifier give 1120 watts at 8 ohms then it connected to the 300 watts 8 ohms speaker it will be safe and if safe then how explain it.
3 - how limiter work and it protect whether speaker or amplifier explain it.

1. If 1120w delivered into 8 ohms resistive (wattage ratings are measured with resistive loads, not speaker loads and wattage figure is given in average power, not peak or peak to peak) the ac voltage across the 8 ohm speaker is approx. 94vac.  Since amplifiers are constant voltage sources and if the power supply is stiff enough to hold up with a 6 ohm load the power into a 6 ohm resistor would be 94x94/6 = 1473w approximately.

2.  You can connect any wattage amplifier to any wattage speaker - if you are careful and know what you are doing.  But, usually, it is desirable to match fairly closely the power amp rating to the speaker power handling capacity. The problem is that whilst amplifier ratings are quite precise and very objectively measured speaker ratings are very fictional and not reliable at all.  Putting too much power into a speaker can damage it quickly.  Keep in mind, speaker power dissipation is a function of the setting of the volume control!

3.  Limiters are not productively used in high fidelity amplification chains but are used often in professional and broadcast systems to keep from going overload in the amplification chains.

Not sure where you are going with your questions, but please send another followup if you need more explanations.


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Audio Design Engineer; systems, loudspeakers, cd/dvd players, etc. I am knowledgeable in all high end audio equipment and installations. MAKE SURE YOU GIVE A MAKE AND MODEL NUMBER AND CAR IF IT IS AN AUTO QUESTION. Note: I am getting some who ask good questions that take a lot of time to research but then the questioner fails to read the answer. Please don't ask questions unless you are seriously looking for an answer. If you find an answer to your question otherwise then let me know with your reply. Thank you.


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