Power usage of full range speakers v. active 3 way

[GBloes]

Let’s say, for the sake of simplicity, you have an 8 channel amp, a full ranger speaker draws 10 amps when playing pink noise at full power. So,... would a mid woofer, mid range and tweeter, each on their own channel actively crossed over, on that amp draw 30 amps (60a for all 6 speakers) or would they draw more or less the same as a full range speaker, closer to 10amps (20a for 3-way plus 20a for rear full range).Without taking into account the amps inefficiencies.

I know a tweeter at 100dB is going to require far less power than a mid woofer at 100dB but I’m not sure if I’m missing anything here.

But, practically, I am wondering what percentage, preferably in amps, of its max power draw a 75w 8 channel amp w/ 80 amp fuse rating would require to run 2 full range speakers and a 6 speaker 3-way set up in the front. Assuming it is CEA compliment and it’s info is actually based off of 20-20,000hz pink noise at operating watts. Insofar as I can tell it’d require the same amperage as an otherwise identical 4 channel amp running 4 full range or 2 full and a passive 3-way, plus whatever inefficiencies. But it feels like I’m missing something.

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[audiobaun 5,000+ posts]

https://www.the12volt.com/wiring/recommended-car-stereo-wire-sizes.asp
You might do some research on here and find the correct answers

 

[GBloes]

Thanks for the link. Lots of good information on there.
Here’s a table I found following links through that link, which illustrates my question fairly well. It’s from a forum to do with home audio so I’m assuming it’s referring to a passive 2/3-way configuration.

In an attempt to clarify and expound upon my initial question, let’s say you have a mid bass speaker crossed over at 350hz (which apparently requires as much power as 350hz-20khz). So let’s say that speaker is playing at 100% of X RMS at X SPL, what percentage of 100% of X RMS would be required to produce 350hz-5khz at the same SPL, and what percentage of 100% X RMS would 5khz-20khz require to produce the same SPL as the rest.

They’re not all going to use the same wattage to produce the same SPL both because of the frequencies they cover, size of the drivers/motors and their locations [(woofers firing at your ankles, mids and tweeters in front of you) which isn’t part of my question].

 

[LsGuy]

It's all relative in reality. Running 3 way active changes a lot. For instance, I have a 3 way active setup in my vehicle. Running in its passive form (using the passive crossover), the set is rated to handle 100 watts rms per side (per 3 speakers). I decided to push each speaker actively with 65 rms to each tweeter, 65 to each mid, and 180 rms to each 6.5. That is 310 rms per side, or over triple rated rms handling. If you were running a coax that was rated at 100 rms, you likely wouldn't want to run triple rms rating to that single speaker, because the tweeter wouldn't handle what the woofer would, the tweeter also wouldn't draw as much power as the woofer, so you would probably end up netting like 250 watts to the woofer etc. Going active gives you the flexibility to manually chose how much power to send individual drivers in the setup.

 

[GBloes]

Thanks for breaking that down. This is something I have yet to wrap my head around; I know the <400hz rang takes a lot more power to reproduce at X SPL than 400-5khz etc. at the same SPL. How much more, that I’m fuzzy on. It’d be simple with a 400-20khz speaker but when that’s handled by 2 speakers crossed over at 5khz,... decibels of 50w @ 5-20khz isn’t the same as 50w @ <400hz.