been clipping, but no damage done?

About 5 months ago, I put in a new head unit, class D mono amp, 2 subs, and a 4-channel amp for my 4 cabin speakers. Since I have been mixing music for about 5 years now, I figured I could just set the gains by ear, by playing a professionally mastered CD that was released recently.

Well now I know that was a terrible idea, because I finally set the gains using test tones yesterday, and everything was slightly off. First of all, I was playing my Alpine head unit at 25 (out of 35). Using the test tones, with the amps turned all the way down, I found out the head unit actually starts clipping at 23. So I kept it at 22, the set the amp gains for the front and rear speakers. I put on a song and WOW I could hear an immediate difference from before. The clarity was MUCH better, and it was even slightly louder, since I had the amp gains lower before (probably because I was using a higher head unit volume before).

Then I set the subs' amp with a lower frequency test tone, and they seem to clip much earlier than I thought. I had it at slightly past 0 / nominal / 12oclock, like maybe at 12:30 or 1oclock. It actually starts clipping around 11 oclock. (I know the amp markers are just markers, and don't actually mean anything)

So I'm wondering why I've been clipping everything, for about 5 months now, but there hasn't been any damage to any of the equipment? I've been on plenty of long drives (hour one way, hour back. plus driving around cities for about 1-2 hours), giving it plenty of time to heat up. Maybe it's possible there has been damage? Maybe I could have set the gains slightly higher without clipping, if I hadn't been clipping everything this whole time?

Here's my list of equipment:
- Head unit: Alpine CDE-141
- Front: pair of 4x6" Kenwood KFC-4675C plates (20W RMS, 60W Peak)
- Rear: pair of 6.5" Alpine SPE-6000 coaxial speakers (60W RMS, 240W Peak)
- Subs: pair of 10" Alpine SWA-10S4 subs (250W RMS, 750W Peak, each)
- Front speaker amp: Legacy LA-160 4-channel amp (300W Peak, unable to find RMS rating, even in the manual)
- Subs amp: Alpine MRV-M500 (500 RMS, can't find a peak rating)

I know, I need to upgrade the front speakers BADLY. I know that rear fill is almost useless. I've been too lazy to buy the construction tools and set aside the time to create enclosures so I can fit bigger speakers in the front. And I know, I need a better 4-channel amp, I got it for free. And I know I went cheap on everything.

As I understand it, clipping is not damaging UNLESS:
- speakers deflect beyond their limits (ie, the speaker is the cause of the "clipping"),
- speakers are not damaged by the higher frequency harmonics caused by clipping,
- electronic clipping is symmetrical ie, equal on both +ve & -ve cycles. If not, a dc offset can occur which can damage (heat) components or speakers,
- other??


Not that I'm an audio expert - there maybe be more - but I've read enough "apparently" contradictory answers because they do not define which case or aspect they are referring to.

Did you use an oscilloscope? Unless that disk you used was recorded extremely hot, I doubt the deck was clipping.

No, I didn't use an oscilloscope. I know it's the most accurate way, but the only one I have access to is huge, and requires AC power. I don't want to bother my neighbors while I set my gains, so I didn't want to use it. I have been driving to an isolated area away from anyone to set my gains.

Here are the test tones I used: https://www.thesuicidaleggroll.com/hosting/test_tones.zip

(from this site: https://www.thesuicidaleggroll.com/gain.htm)

I looked at it in audacity, seems to go right to -0.1dB, the perfect spot.


I'm pretty sure I could hear the highs clipping. It clearly got distorted and turned into two seperate sounds, instead of one clean sound wave. The CDE-141 is a very low end Alpine model.

Now the subs, I'm not so sure were clipping, because it might have just been causing some plastic in the trunk to vibrate. I try to move the subs away from touching anything while I am adjusting the gain. I also have tried to dampen the trunk to the best of my ability, and tighten everything down as good as possible, especially the plastic trim. I did double check the gain setting today with a different frequency test tone, 140Hz instead of 60Hz. (with LPF as high as it can go, since I can't turn it off.) And it seemed to clip at around the same 11 oclock setting. I can try again with an even higher frequency to make sure it's not something vibrating.