Help understanding output vs volume

[stang233]

I am having a hard time understanding power output vs. Volume. If I have an amp that is 1000 Watts RMS and the volume is at 25% is the amp output near 250 watts. Meaning a draw of around 20 amps? Furthermore if the gains are set properly in the volumes at 50% is it at 500 watts or around 40 amps draw

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[fithwheel]

Research impedance rise.

 

[stang233]

I believe I understand how frequency and resistance affects the output of the amp but all of the testing I can find online the volume/signal is turned up to right before clipping and watts are evaluated. I'm still trying to figure out how much power an in amp draw if you only turn the volume up slightly

 

[THATpurpleKUSH 5,000+ posts]

Power in relation to volume is not linear, it's logarithmic.

 

[stang233]

At average listening what output could you expect from a thousand watt amp?

 

[THATpurpleKUSH 5,000+ posts]

At average listening what output could you expect from a thousand watt amp?

There are wayyyyyy too many variables to give you the simple answer you are looking for.

 

[stang233]

There has to be a way to generally quantify it. If a amp is on and speaker hooked up with no sound coming out is it still generating its max rms?

 

[THATpurpleKUSH 5,000+ posts]

There has to be a way to generally quantify it. If a amp is on and speaker hooked up with no sound coming out is it still generating its max rms?

No it will not.

Let's take a couple steps backwards and have you explain what you are trying to accomplish and why.

 

[stang233]

Thank you for your time. I would like to put a 1000 watt amp in my 15 mazda 6. The alternator is 100 amps. 1000 watts is pushing it with all the options of cars now daya, heated seats, mirrors, ext I just was wondering what the draw would be at average listening. I don't want to be at the max of the alternator. I do not plan on playing full tilt too much.

 

[THATpurpleKUSH 5,000+ posts]

What kind of amp are you planning on using-exact make and model #? Also what sub, what kind of box, what are your listen habits or overall goals for the bass?

When you max out the alternator you experience voltage drop which can be monitored with a voltage meter connected to the power input terminals of the amp. You can upgrade the stock battery and add extra batteries but it will only get you so far (~2-3krms)

 

[Popwarhomie 5,000+ posts]

Hook up a volt meter and send it. Monitor your voltage and go from there.

 

[Jeffdachef 5,000+ posts]

Thank you for your time. I would like to put a 1000 watt amp in my 15 mazda 6. The alternator is 100 amps. 1000 watts is pushing it with all the options of cars now daya, heated seats, mirrors, ext I just was wondering what the draw would be at average listening. I don't want to be at the max of the alternator. I do not plan on playing full tilt too much.

this literally comes back to researching impedance rise.
on music you'll never EVER get the 1000 watts because you will never see the ohm load you are wired to. Which means you'll never draw anywhere near 100 amps of current unless you are clipping the hell out of that amp. Not trashing your amp by any means, it happens to every amp, its unavoidable physics.

 

[Jeffdachef 5,000+ posts]

Hook up a volt meter and send it. Monitor your voltage and go from there.

the only logical solution. All these people are scaring themselves sh*tless for no reason before they even hook anything up lol

 

[n2audio 5,000+ posts]

I will just throw out -- in general -- if you don't blast it that often your alt should be fine.

Think of it this way -- your average 50-100w factory set up can honestly get pretty loud, right? You won't be drawing much more from your aftermarket "1000w" set up if you listen at similar levels. But when you start moving from loud to exceptionally loud your power requirements increase exponentially. It takes about a 10x power factor to yield sound that's 2x as loud.

Even so -- say you're blasting your 1000w set up at near full volume - and drawing, theoretically, ~100A. It's actually nowhere near that much simply because of the nature of music. There may be bursts that require close to 100A, but when averaged out over a few seconds with the softer/quieter moments it's not likely your actual current draw would exceed 50A or so -- due to something called crest factor (wave peak power vs average).
Impedance vs resistance is part of it, but crest factor is big as well.

 

[stang233]

Thank you all for the help and input. If a speaker is hooked up can u measure watts with Multi Meter if u touch the leads on the amp?