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Discussion Starter #1 (Edited)
Im just trying to better understand how speakers and amps work together. For example, lets say you have a 600/4 amp to active 2-way front tweeters and midranges, is 600 watts being fully utilized at all times? Am I sending equal amperage to every speaker, meaning mids and tweeters are receiving the same amount of power? Or do speakers only draw what they require from the amp?

Is a 1200/1 amp too powerful for a 500rms sub? or will the sub only draw what it needs from the amp.

Much appreciated!!
 

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Amps don't 'force feed' power into anything... the speaker draws what is needed. (in simple terms)

For instance; a decent tweeter will (at best) draw 15 watts. Typically less.
But you can feed them with a 150 watt per channel amp - no problem.
It's just unitilized potential power in the amp.

As far as damaging a speaker; you're more likely to do it with an underpowered amp (creating distortion).
 
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I'm gonna disagree with that. Speakers don't "draw" anything. Speakers are a passive device. They literally do NOTHING. You send your amplifier a musical signal. It amplifies that signal per the gain setting. The amplifier outputs an electric signal of "XX.XX" volts. That voltage potential is sitting at the + and - of the speaker output on that amplifier. When you attach a speaker that voltage becomes current running through that speaker. Generically speaking, a 4 ohm speaker with a 40 volt signal will have 10 amp signal. If you're amplifier is presenting 400 volts it will have a 100 amp signal. This is a super simplified explanation but the theory is the same.
 

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I agree with OG. It’s the signal going into the amp, plus the gain settings / other adjustments, that then get “pushed” out to the speakers.

You want to make sure the signal being pushed by the amp is clean (no distortion / clipping) by feeding a clean source, and setting gains/adjustments appropriately.
A distorted/clipped signal to your speakers is far worse than sending them more power than they can handle.

As for power handling, the watts are dictated by the music and gain adjustments, so if it’s a 100w rms for a particular channel, it only sees 100w at max volume, but at all other times will be somewhere less than that (turn down volume, quiet part of song, etc)

Hope that’s helpful.
 

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Don't forget the difference in musical energy and relation to power needed plus how we hear. This is why resistors are used in passives and different gain adjustments in active are used.

Man & Machine... Power Extreme!
 

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There are bits and pieces of good, and bad info here.

Yes, speakers are passive, the only role they play in determining how much power they receive is with their impedance. The amplifier, and source determine the output. The head unit, DSP, and amps (as well as the recording level of the track itself) all have their own gains, and it's this combination of gain settings that determine the power going to a speaker. The speaker is simply the receiver of the power determined up the chain.

It's important to clarify some of the distortion/clipping comments. Distortion is completely harmless by itself. Clipping is a type of distortion that has the potential to damage speakers, but it isn't automatically going to harm anything. Clipping only becomes harmful when it contains more power than the speaker can handle. For example, using a 50 watt channel connected to a sub with 2k watts of power handling, and clipping the signal won't harm the sub. Clipping is dangerous not because it sounds bad, but because it contains a much higher average power than a clean wave, and a clipped (square) wave does not allow the speaker to cool itself correctly, the extra heat can cook the voice coil.

Your tweeters will receive far less power than low frequency speakers for several reasons. First, your gains will be adjusted so that you have a relatively balanced sound, and the frequencies in the low to mid range of a tweeter's range are really easy for us to hear, so they don't need to be loud to sound balanced. Secondly, tweeters tend to have a higher sensitivity than low frequency speakers (not always though), this means they get louder off of less power. Finally, the recording itself will create less power in the high frequencies than the low frequencies.

Power determines SPL. Turn up the volume knob and you increase power, and SPL. Turn down the volume and you reduce SPL, and power.
 

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I'm gonna disagree with that. Speakers don't "draw" anything. Speakers are a passive device. They literally do NOTHING. You send your amplifier a musical signal. It amplifies that signal per the gain setting. The amplifier outputs an electric signal of "XX.XX" volts. That voltage potential is sitting at the + and - of the speaker output on that amplifier. When you attach a speaker that voltage becomes current running through that speaker. Generically speaking, a 4 ohm speaker with a 40 volt signal will have 10 amp signal. If you're amplifier is presenting 400 volts it will have a 100 amp signal. This is a super simplified explanation but the theory is the same.
Yeah, I guess I didn't explain that very well - which is why I put; (in simple terms).

You are correct. The speaker is just a dumb resistive load. It doesn't technically draw anything. But it is a resistive load, which draws current.
Draw is just an electrical term (and maybe improperly used), which doesn't imply that the speaker is physically 'pulling' power.
It doesn't pull (or draw). It just sits there and waits for power to come to it.

Kinda like saying; "you are drawing a glass of water from the tap". The glass isn't physically drawing anything... but that's the term used.

My point was mainly that; amps don't force feed power into speakers.
Meaning that if you have 100 watts per channel (potential) in your amp, that doesn't mean that the speaker is getting 100 watts all the time.
 
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