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Discussion Starter #1
This is not as simple as the title may sound haha. This has to do with rms/peak compared to amps.

So driver x calls for 100 watts rms. obviously anything under that will not hurt the driver. (Take clipping out of the picture for this example.) but to much power can blow the driver. An amp rating of 100 watts would be perfect for said speaker.

Question is how do people run 2-3 times the amount of power to a driver and it still operate properly?
 

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It's clean power. When you have more power you have more headroom so your not pushing your equipment to the max. When you do that there is less of a chance of a clipped signal. When the signal clips it sends a bunch of power and distortion thru the system. A clean sine wave, if I remember correctly, produces about 70% while a clipped signal sends 100% power
 

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Some of that depends upon how the speaker designers arrived at what they consider a safe operating limit.
The speaker isn't getting a continuous tone at the maximum limit with music, so an amp that is capable of producing wattage in excess of the speaker's rating isn't destined to damage it.
Limiting the frequencies to the speaker are the most important factor. Especially with tweeters!
 

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It's clean power. When you have more power you have more headroom so your not pushing your equipment to the max. When you do that there is less of a chance of a clipped signal. When the signal clips it sends a bunch of power and distortion thru the system. A clean sine wave, if I remember correctly, produces about 70% while a clipped signal sends 100% power
Small portion of it. As well as what I'm about to say

We have to remember here we have a crossover in play here. When manufactures rate the drivers its free air and full range for the most part (some may do it slightly differently) and the final (final RMS value) number takes into account generally the range these drivers will play.

Say a driver is rated at 100W rms and we add a crossover at 80hz with a slope around 18-24db/oct. This in turn increases the thermal capacity of the speakers voice coil because the speaker isn't playing 20-80Hz @ full power.

You have to remember that, as many guys here have said, when the manufactures of the speakers give the rating its also generally conservative. It's a value where you can play the driver 24/7/365 and not have a issue
 

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Ok, here is the real deal.

Most people who "run" 2-3x the rated power to their speakers simply have that much available, the speaker never actually gets that power. People (especially on this site) love to brag about how much power they "run" to their speakers, despite the fact that the speakers almost never get that power.

However, there are certainly times when their extra power does get used. It's only for fractions of seconds, but it happens during brief, dynamic passages when a particular note is much louder than the average level and when their listening level is already at a volume level which is high enough for the dynamics to require excessive power. The idea is that if your amplifier has 2-3x more power than you need, then even those dynamic moments will be reproduced accurately. With a lower powered amp those fractions of second moments get clipped, and the amp cannot produce them accurately. They are usually so brief that you would ever be able to hear whether or not it was clipped or accurately produced.

Dynamic headroom is a good thing, but it isn't exceptionally noticeable, especially in a car. Keep in mind that there is a direct relationship to power and volume level. So, if you don't listen loudly, extra power won't benefit you (with the exception of those slightly audibly fractions of seconds dynamic moments). Getting as much power as you can afford can be great, but some people love to take it to the extreme thinking that they are getting something really special from it, and they really aren't. The 2-3x power is actually pretty reasonable compared to some that I've seen.
 

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Yes. Average power is what counts, not the not maximum one.

And the sound is more enjoyable at mid to mid high volumes.

And yes Not crossing lower than 80hz will be safer if doubling the power in a door without a sealed enclosure
 

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First ask yourself how manufacturer determined speaker power handling - at what conditions.... - thermal and mechanical
 

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Discussion Starter #9
Thanks for the explanations! So the speakers im going to use are rated at 150 rms. the F's of the speaker is 44 hz. If I set the crossover at 60 hz, how much would you guys throw at them and not have to worry about them blowing?
 

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Mine handle 140W, I have 300W at 14V for each mid bass, I got the DSP output level reduced to 80% I assume 240W is the number.

Since music has peaks and lows it's the average power that counts

I have mine crossed at 90hz my EQ bands are flat or below flat, the 60hz band is 4 steps below flat.

I would not cross any speaker below 70hz with extra power, and would suggest NOT to have EQ bands above flat, and never use loudness

Every door is different I have more bass than I need in the front.
 

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Another thing, you could cross at 60 Hz of lower with 2X or 3X the power, if the speakers can handle it and if you have an enclosure built for them with the right volume, a kick panel gives you more flexibility to get the most from power and crossing them lower. In doors, it is basically IB and High passing at a low frequency can damage the speaker with more power and high excursion, that is another reason I would not cross a speaker below 80Hz in a door, and if you play music with low bass (hip hop etc) , then that is where you risk damaging the speaker.
 

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Discussion Starter #12
These will definitely be mounted in the door. The speakers I am referring to are Stereo Integrity's new 6.5". And I listen to rock and hip hop. Both at high volumes. I am just trying to figure out my amp situation. Ive been looking at the Precision Power Phantom 900x4. at 4 ohm they are 125 per channel. but the Stereo integrity are Dual vc. So they will run at 2. So that puts this amp at 300 RMS per channel IIRC. They rest of the system is HAT L3v2 and a JL 12W6v2 ported.
 

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Those SI drivers have good excursion and appear to be very well made. I doubt there will be any issues. Like it was mentioned those power handling ratings are conservative and they always handle way more than their rated power handling.

If you have a DSP, you can reduce the output level.

There are different ways you can reduce or limit the power to them, when you set the gains you can start at 80 to 90% or higher HU volume. With the loudest track and bass you have, if done by ear, This will limit playing louder tracks at higher volumes.

You can also use a DMM, and do your calculations for say 225W or 25OW for 2 ohms, that will be 22 and 23 volts, or 200 watts would be 20 volts if that makes you feel better, also with 75-90% volume. Keep in mind some manufacturers, make false claims on power ratings.

Or also by ear, detecting distortion at the max volume you will be listening, and reducing the output level or gains when you hear it. When doing that you may want to disconnect or turn off the sub to hear the bass distortion from the mid bass drivers.


I have only had mine with the extra power for a few weeks, It was hard to get used to, I hardly ever need to pass 23 out 35 to get clean good sound, only when the music was recorded at low volumes, I play at 30 plus, but never had any detectable distortion or noticed any stress with the music I play.
 

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There are many ideas flying around in this thread. I recommend understanding what a sine wave is and the ideas of peak to peak and RMS really are in reference to it.
 

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This is not as simple as the title may sound haha. This has to do with rms/peak compared to amps.

So driver x calls for 100 watts rms. obviously anything under that will not hurt the driver. (Take clipping out of the picture for this example.) but to much power can blow the driver. An amp rating of 100 watts would be perfect for said speaker.

Question is how do people run 2-3 times the amount of power to a driver and it still operate properly?
Just because the amp can provide three times more than the rated power does not mean that it's actually sending all that power to the speaker all the time. The music content is dynamic and most of the time calls for significantly less power than what the amplifier can provide. Moreover, there exist dozens of tutorials on how to set the amplifier gain knob properly so that you never blow your speaker or overdrive the amplifier.

By the way, according to a lot of people, overdriving the amplifier (asking for 1500watts continuous, when it can do only 1000) is far more damaging to the speakers, and so part of the amp gain setting process is to proven this situation.
 

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Discussion Starter #16
There are many ideas flying around in this thread. I recommend understanding what a sine wave is and the ideas of peak to peak and RMS really are in reference to it.
I have seen a sine wave before. I had my last radio tested with an O scope. I know when the wave goes above or below the top and bottom of the graph it is clipping the signal. Is this what you were meaning or is there more to it?

Just because the amp can provide three times more than the rated power does not mean that it's actually sending all that power to the speaker all the time. The music content is dynamic and most of the time calls for significantly less power than what the amplifier can provide. Moreover, there exist dozens of tutorials on how to set the amplifier gain knob properly so that you never blow your speaker or overdrive the amplifier.

By the way, according to a lot of people, overdriving the amplifier (asking for 1500watts continuous, when it can do only 1000) is far more damaging to the speakers, and so part of the amp gain setting process is to proven this situation.
Yes I do realize that. I am not wanting to overdrive my amp. This is why I am asking about power trying to figure it out. The amp I am looking into is precision power phantom 900x4. 125x4 at 4 ohm, 225x4 at 2 ohm, 450x2 bridged at 4ohm. I've been told 125 is perfect for my HAT L3V2's. But as far as the Stereo Integrity, I believe it calls for 150. If that's the case, and the gain is set where they will see 225 each, will that be ok?

The way I understand it, the speakers will constantly see 225 (when the volume on the HU is at its max, after being set for the unclipped signal.) but they call for 150 rms. in my head the constant 225 will either blow the driver or make it over heat.
 

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I've been in a lot of sq cars over the years and the ones running a ton of power have almost always been way more dynamic than lower power systems. I recently sold my pdx5 back to my buddy and put my 8 ohm frontstage on just my Mosconi One 120.4 rated at 120x4 at 4 ohms. My available power for the fronts is about 1/3 of what it was with the pair of bridged amps and the dynamics are suffering. I wanted to go back to straight up a/b amps up front which is why I let the pdx go back to my buddy to put in his daughters truck. Think of it this way...it's like a fullsize truck with a regular v6 vs the same truck with the biggest engine available. I may have a HEMI turning 3.92 gears but that power rarely ever gets used. Same analogy with running big power to speakers. I did notice the tensile leads on my 2" widebanders in the dash were a little burned when I pulled them out recently but it sure won't stop me from running big power to them for the sake of dynamics on something as inefficient as most widebanders these days. They're inexpensive enough to replace every year of 2 if needed.
 

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JSM-FA5 said:
The way I understand it, the speakers will constantly see 225 (when the volume on the HU is at its max, after being set for the unclipped signal.) but they call for 150 rms. in my head the constant 225 will either blow the driver or make it over heat.
I think this is where you're getting confused. Let's say you set your gains to be at full power when your HU volume is at the max. If that is the case then theoretically you would send 225w to your mids while playing a 0db continuous noise track. But the reality is that music isn't continuous so it doesn't always send 225w. It taps into those 225w to send the power needed.

I have 2ohm Focal mid bass and are powered by a 250w/ch @ 2ohm amp. I set my gains properly and never hear distortion or strain from my mids.

Maybe this analogy will help:

Let's say your amp is like a car engine. Just because you have a ton of power doesn't mean you automatically burn out every time. You have the power on hand to go fast as needed but in reality you probably use a fraction of that power in everyday driving.



Sent from my SAMSUNG-SM-N900A using Tapatalk
 

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Discussion Starter #19
I understand that analogy. And I realize the speakers do not always see the rated RMS power. But if they are rated at 150 RMS, this means they can handle a constant 150 for a test tone. (as I understand it anyway.) I also know speakers have a peak power limit. This is reffering to the dynamics I assume. But do the amps also have a peak power out put just like Speakers? If so wouldnt that blow the driver?
 

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Your over-thinking this. Double or triple what a driver can handle is a wonderful thing if you know how to use it. Proper setup and common sense is all you need to keep from blowing up speakers.
 
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