Bass Test Tones

[Johannes]

Can playing test tones like the one on this site: http://kan3.freeservers.com/ ever harm a subwoofer if you play really low ones?

[sr20de4evr]

If you push it beyond its mechanical (bottoming out) or thermal (voice coil melts) limits then yes, otherwise no.

[Johannes]

I'm not talking about giving it way too much power with the gain way up or anything like that... I mean playing a 10hz test tone on a subwoofer that's only rated for 15hz and up, something like that.

[sr20de4evr]

no that won't cause any problems


It's just a voltage that changes over time, as long as you don't exceed the mechanical or thermal limits of the speaker then it doesn't care what you're feeding it

[Johannes]

Okay, kinda what I figured... thanks.

[CBFryman]

but remember the lower the frequincy the longer the voltage stays close to peak, so at least play them at -3dB to be on the safe side, especailly since a lot of amps clip just because the circutry cant handle the current peaks when frequincies drop really low.

[Johannes]

What exactly do you mean by -3db... are you referring to adjusting it on the head unit?

I played them, you can only really hear them around 30hz+, otherwise you can't really hear it too well, it's just kind of a popping...

It's like the bass in Snoop Dogg's "Suited and Booted" and about a million other songs... low frequencies sound awesome, I really should get a good setup!

[PaulD]

Originally Posted by CBFryman

but remember the lower the frequincy the longer the voltage stays close to peak

NO a 10 Hz sine wave has exactly the same duty cycle as a 5KHz sine wave if the peak level is the same. What makes the voltage (power) stay near the rails is called clipping.

[CBFryman]

paul, i wasnt refering to staying AT peak longer i was refering to staying at higher voltage for a longer duration... over a set period of time the ammount of time each spends at any particular amplitude is the same HOWEVER the lower the frequincy the less often the amplitude changes dramatically.
see pictures, the first is a 10hz signal and the next a 5kHz signal. also look at the time elapsed at the top.






and BTW
-3dB means it is recorded at 1/2 amplitude.

[sr20de4evr]

Originally Posted by Johannes

What exactly do you mean by -3db... are you referring to adjusting it on the head unit?

I played them, you can only really hear them around 30hz+, otherwise you can't really hear it too well, it's just kind of a popping...

It's like the bass in Snoop Dogg's "Suited and Booted" and about a million other songs... low frequencies sound awesome, I really should get a good setup!

You hear popping below 30hz? That's the sub bottoming out, that's what I was warning you against in my first post. Are the subs ported? I couldn't see crappy output and high excursion below 30hz unless the subs were in a high-tuned ported box.

[sr20de4evr]

Originally Posted by CBFryman

paul, i wasnt refering to staying AT peak longer i was refering to staying at higher voltage for a longer duration... over a set period of time the ammount of time each spends at any particular amplitude is the same HOWEVER the lower the frequincy the less often the amplitude changes dramatically.
see pictures, the first is a 10hz signal and the next a 5kHz signal. also look at the time elapsed at the top.






and BTW
-3dB means it is recorded at 1/2 amplitude.

We see what you're saying, but your argument makes no sense, the speaker will behave the same way with either of those (except the sub's inductance will limit the output of the 5khz wave), as will the amp.

And -3dB is 70% of the original amplitude, half would be -6dB.

[Johannes]

It's a sealed box... and it really isn't quite a popping noise, more like the sub moving in and out really fast, kind of a thumping noise...