Myth Or Fact: Under Powering a Subwoofer?

[Jeffdachef 5,000+ posts]

How do you in fact "Clip" a sub with the amplifier? Im new to this.

You are telling the amp to make more power then it can possibly hope to achieve. It cannot physically do it without causing major distortion to the signal. Thats why you have noobs buying 400 watt amps powering 600 watt subs thinking they will be safe, but when they have it all set up and its not hitting as hard as they want even though they are pretty much maxed out on power output from the amp, They start cranking stuff up even more. They think its louder but its actually distortion and it leads to blown subs.

Theres impedance rise and voltage drops to account for so even a reputable 1000 watt amp would probably only make 600-750 watts after rise and voltage drops. 400 watts would be a lot less which is pretty much like tickling the sub. Thats why most people encourage headroom with power. More loudness without the distortion.

 

[AARKing419]

You are telling the amp to make more power then it can possibly hope to achieve. It cannot physically do it without causing major distortion to the signal. Thats why you have noobs buying 400 watt amps powering 600 watt subs thinking they will be safe, but when they have it all set up and its not hitting as hard as they want even though they are pretty much maxed out on power output from the amp, They start cranking stuff up even more. They think its louder but its actually distortion and it leads to blown subs.

Theres impedance rise and voltage drops to account for so even a reputable 1000 watt amp would probably only make 600-750 watts after rise and voltage drops.

What would they be cranking up? The Gain & subsonic?

 

[Jeffdachef 5,000+ posts]

What would they be cranking up? The Gain & subsonic?

Anything really. Gain, bass boost, head unit EQ settings, Loudness feature, head unit volume, subwoofer level and whatever bass engine super boost feature BS they have on the head unit.

Subsonic filter is just a filter the cuts off frequencies lower then the specified point, cranking that up does not blow your subs, having it set too low with a sub in a ported box will cause death via mechanical failure.

 

[AARKing419]

Anything really. Gain, bass boost, head unit EQ settings, Loudness feature, head unit volume, subwoofer level and whatever bass engine super boost feature BS they have on the head unit.

Subsonic filter is just a filter the cuts off frequencies lower then the specified point, cranking that up does not blow your subs, having it set too low with a sub in a ported box will cause death via mechanical failure.

So then how do you know what to turn your amp settings to?

 

[Jeffdachef 5,000+ posts]

So then how do you know what to turn your amp settings to?

How to Adjust Amplifier Gains Using a Digital Multi-Meter | Learning Center | Sonic Electronix

Note that method only works when you have amps of reputable quality. Any garbage brand of amps that does not do rated power will = clipping and distortion.

 

[AARKing419]

How to Adjust Amplifier Gains Using a Digital Multi-Meter | Learning Center | Sonic Electronix
Note that method only works when you have amps of reputable quality. Any garbage brand of amps that does not do rated power will = clipping and distortion.

Is A BC 3500 worthy?

 

[Jeffdachef 5,000+ posts]

go right ahead man. As long as you have the electricals to back it up.

Forgot, another cause of clipping even when you've set your gains properly.

Voltage drops. Amps make less power at a lower voltage and when the voltages drop very low, you pretty much will run into clipping since you've set the gains on the amp to make the power it makes at 14.4 volts.

 

[shizzzon 10+ year member]

^^^ the reason that happens is because the dc voltage input is solely responsible in unregulated power supplies to the ac output rail potential.

If a gain is set with no load on it... this is the funniest because the user will always experience bad results.

But what happens is when dc voltage drops, the rails headroom drops as well.

this just doesnt reduce power but headroom. That results in clipping when volume level remains the same but dc voltage is lower than expected.

 

[akheathen Premium Member]

lack of dead-time and movement= lack of cooling. you can push a head unit on a 500watt rms sub as loud as you want, and the only thing that could cook it is if the chip shorts to dc, and magically the circuit can pass enough current to overheat the coil.... where you get in the danger zone is when you have enough power to effectively overheat a static coil and just crank it past rms a lot. blame it on clipping, blame it on distortion, blame it on Tinkerbell.... it's just current passing longer than the time it should be, and lack of movement..... and someone who doesn't know how to recognize bass vs noise.

 

[dagormz]

[quote name='gckless']If you're clipping, you're giving it more than RMS, just generally. Depends on the severity of the distortion, but clipping will drive your power level up exponentially.

For all intents and purposes of this discussion, I think clipping should be disregarded. That can happen at any power level.[/QUOTE]

umm, i know i'm kindof new to car audio but i have a decent background in electrical engineering. Isn't clipping when your HU puts out a distorted signal in which has a flat signal at the crest and though of the sine curve essentially giving DC current to the speaker, making the coil stick for a second and stressing it a lot. I don't believe clipping has anything to do with RMS rating. Just that @What was that\?; putting 5k into a 150 sub. It doesn't blow because it probably has a decent cone and he probably has a HU that gives a clean signal.

 

[What was that? 10+ year member]

Clipping is basically sending the speaker a distorted signal.

This post popped up way behind. **** internet!

 

[dagormz]

Clipping is basically sending the speaker a distorted signal.
This post popped up way behind. **** internet!

Yeah, I should probably finish reading the thread before responding.

 

[hispls 5,000+ posts]

[quote name='dagormz']umm, i know i'm kindof new to car audio but i have a decent background in electrical engineering. Isn't clipping when your HU puts out a distorted signal in which has a flat signal at the crest and though of the sine curve essentially giving DC current to the speaker, making the coil stick for a second and stressing it a lot. I don't believe clipping has anything to do with RMS rating. Just that @What was that\?; putting 5k into a 150 sub. It doesn't blow because it probably has a decent cone and he probably has a HU that gives a clean signal.[/QUOTE]

Any amplification circuit has a limit and will clip the signal if you try to over-drive it, so head unit, EQ, amps, or anything else including starting with whoever records or mixes the recording.

5000W is roughly the amount of heat that every burner on the top of an electric stove uses put together. There is no conventional loudspeaker that will take that much heat for very long..


[quote name='What was that?']Clipping is basically sending the speaker a distorted signal.

This post popped up way behind. **** internet![/QUOTE]


And while we're all wringing our hands about distortion and the new boogeyman "clipping", virtually every rock musician since the Beatles has over-driven their amps into clipping/distortion on purpose to get a different sound out of their instruments.

 

[dagormz]

Any amplification circuit has a limit and will clip the signal if you try to over-drive it, so head unit, EQ, amps, or anything else including starting with whoever records or mixes the recording.
5000W is roughly the amount of heat that every burner on the top of an electric stove uses put together. There is no conventional loudspeaker that will take that much heat for very long..

And while we're all wringing our hands about distortion and the new boogeyman "clipping", virtually every rock musician since the Beatles has over-driven their amps into clipping/distortion on purpose to get a different sound out of their instruments.

Yes, exactly. It is the amplifier and not the speaker. Driving a speaker with more power than its designated rms rating is not clipping. Clipping is once again dc current at the crest and through of the sine wave, whether from the amplifier or the head unit.

Sent from my iPhone using Tapatalk

 

[What was that? 10+ year member]

Am I wrong by keeping it simple and saying distorted signal to speakers? Who cares about technical definition at this point when some that does not understand electrical is trying to get a simple and understandable answer.

Also for example reasons who cares what a what a sub can take. I was saying that we are not always underpowering sub's.

It would be nice if we could skip all technical crap and give someone an answer in simpleton terms and leave at that. This way when they want learn the technical aspect they are not afraid of the answer.