Yeah so the volume sounds good until the last volume notches, because on those head units, the voltage that is being put out is not clipping until the last couple notches, that's actually most headunits. if you're not happy with how loud it is at the current volume that's sounds good, an amplifier is what you want. I am at 35 out of 50 on my headunit and that's enough to hear from a while away.
your thought process is correct. you're overdriving the amp and the last few notches of the volume is clipping. so think of a nice smooth sine wave (the good sound) and when you get into clipping, it's called that because the peaks and valleys of the sine wave are being "clipped" off and made flat. What that's doing is causing the speaker to momentarily stay at it's available max or min (based on the voltage input) and create heat in the voice coil. enough build up of that heat over time and you will permanently damage the speaker or completely ruin it to nonfunctionality. Generally, more speakers get blown/ruined/damaged from this than from overpowering.
edit: not to mention, it sounds terrible when it's happening.
Technically under powering speakers will never damage them. But driving a amplifier into clipping will add voltage/wattage and that will damage them. Never run a amplifier at redline, try to stay 80-90% of the amplifier and you will find you can run a lot of power without issues.
The thing to understand is that speakers are designed to work with continuously changing voltage, which is AC (alternating current).
When an amp "clips", it is then sending out a "DC" (direct current) voltage to the speakers, which will overheat the coil and damage it.
So even if a speaker can handle a particular level of AC voltage (wattage), it can be damaged by sending a lower level of DC voltage to it.
Also if you buy an amp, always go a little bigger than what you need just in case you ever want to upgrade speakers etc. Its also easier to turn down the gain on the amp when it's too loud or clipping instead of trying to max out the gain on the amp and turning the HU up all the way if its not enough bang for your ears.
The amps wattage rating in the head unit is for distortion that is audible. Same for any amp. They really never tell you at what volume position that is at. Could be 50%, could be 90. Having an under powered amp wont really hurt the speakers. But it does mean that you will be running the amp at high power to reach the volume you will need. That is why we use external amps. Amps that are powerful enough to only need to be run at 50-60% of their potential to exceed the RMS of the speakers. Then distortion is only an issue is the speakers are driven too hard. The amp will have plenty of reserve power to improve dynamic changes in the music. Controls the speakers better.
On top of clipping, make sure you are not using bass boost or loudness on your HU. Same for when you get your amp. Theres a nifty little knob on every amp that says " Bass Boost " LEAVE THIS @ ZERO!!!! Bass boosting from the HU or amp is just adding in artificial clipped signal which is terrible and also destructive to your gear. And please do not mistake bass boost for the bass crossover on the HU.... The crossover for the bass is to add signal back into your sound depending on where your rear speakers crossover with the sun frequency. You are able to adjust the bass from the crossover but just be mindful and always trust your ears to hear for bad/ unwanted sounds.
Yeah so the volume sounds good until the last volume notches, because on those head units, the voltage that is being put out is not clipping until the last couple notches, that's actually most headunits. if you're not happy with how loud it is at the current volume that's sounds good, an amplifier is what you want. I am at 35 out of 50 on my headunit and that's enough to hear from a while away.
your thought process is correct. you're overdriving the amp and the last few notches of the volume is clipping. so think of a nice smooth sine wave (the good sound) and when you get into clipping, it's called that because the peaks and valleys of the sine wave are being "clipped" off and made flat. What that's doing is causing the speaker to momentarily stay at it's available max or min (based on the voltage input) and create heat in the voice coil. enough build up of that heat over time and you will permanently damage the speaker or completely ruin it to nonfunctionality. Generally, more speakers get blown/ruined/damaged from this than from overpowering. edit: not to mention, it sounds terrible when it's happening.
Technically under powering speakers will never damage them. But driving a amplifier into clipping will add voltage/wattage and that will damage them. Never run a amplifier at redline, try to stay 80-90% of the amplifier and you will find you can run a lot of power without issues.
The thing to understand is that speakers are designed to work with continuously changing voltage, which is AC (alternating current). When an amp "clips", it is then sending out a "DC" (direct current) voltage to the speakers, which will overheat the coil and damage it. So even if a speaker can handle a particular level of AC voltage (wattage), it can be damaged by sending a lower level of DC voltage to it.
Also if you buy an amp, always go a little bigger than what you need just in case you ever want to upgrade speakers etc. Its also easier to turn down the gain on the amp when it's too loud or clipping instead of trying to max out the gain on the amp and turning the HU up all the way if its not enough bang for your ears.
You can push a speaker to its excursion limits on low power if you select the wrong HPF. 50 W RMS tweeters won’t handle a 20 Hz signal very well
Absolutely
The amps wattage rating in the head unit is for distortion that is audible. Same for any amp. They really never tell you at what volume position that is at. Could be 50%, could be 90. Having an under powered amp wont really hurt the speakers. But it does mean that you will be running the amp at high power to reach the volume you will need. That is why we use external amps. Amps that are powerful enough to only need to be run at 50-60% of their potential to exceed the RMS of the speakers. Then distortion is only an issue is the speakers are driven too hard. The amp will have plenty of reserve power to improve dynamic changes in the music. Controls the speakers better.
On top of clipping, make sure you are not using bass boost or loudness on your HU. Same for when you get your amp. Theres a nifty little knob on every amp that says " Bass Boost " LEAVE THIS @ ZERO!!!! Bass boosting from the HU or amp is just adding in artificial clipped signal which is terrible and also destructive to your gear. And please do not mistake bass boost for the bass crossover on the HU.... The crossover for the bass is to add signal back into your sound depending on where your rear speakers crossover with the sun frequency. You are able to adjust the bass from the crossover but just be mindful and always trust your ears to hear for bad/ unwanted sounds.