Bass cutoff

[nobb]

Hey
I have some computer speakers, and I have tested them with a ton generator. They seem to be able to produce sound down to 30hz, but not at a very good quality. I also have a software equalizer running, and it is a 10 band. The last 3 frequencies are at 30,60,120 hz. When watching movies, I set it to flat, but when listening to music(I am a bass lover), I increase the 30hz to +10dB and gradually increase the 60 & 120 hz. My question is, would it be ok to simply cutoff the 30hz?(-20dB), while just increasing 60hz to +10dB since my subwoofer isnt producing the 30hz at acceptable quality. Would this produce more percieved bass? I think that is the technique that maxxbass uses (http://www.maxx.com/). I am a newbie, so any opinions would be greatly appreciated. Thanks!

 

[rsaavedra]

Quote:

Originally Posted by nobb My question is, would it be ok to simply cutoff the 30hz?(-20dB), while just increasing 60hz to +10dB since my subwoofer isnt producing the 30hz at acceptable quality. Would this produce more percieved bass? I think that is the technique that maxxbass uses (http://www.maxx.com/). I am a newbie, so any opinions would be greatly appreciated. Thanks!

Honestly I think that's a bad idea. The real solution should be to get a better sub with a more smooth and nondistorted rolloff. If sticking to your current sub, I would probably consider your intentionally added roll off, to simply get rid of that distortion in the lowest extreme, I think an earlier rolloff is better than a bad sounding lower extension.

But the extra bumpiness around 60Hz is totally unjustified, and way excessive (10db's!!!). Unless your sub had a way low freq response over there with respect to rest of the spectrum played by your speakers, there's no need to equalize/calibrate it with such huge bump. If you do this, you'll get accostumed to some largely deformed bass sound, and that bump there all the time should sound quite terrible anyway.

 

[ooheadsoo]

I can't imagine it not distorting, if not clipping at +10. My amps clip if I even do +1 and hit the specified frequency full blast. A better (free) solution would be to lower the rest of the spectrum and keep the bass at 0. However, do realize that this is far far faaaaaaaaar from "audiophile."

 

[nobb]

Thanks for you replies. I know getting a better subwoofer would be a better idea, but it costs money. My sub distorts very quickly with the +10dB boost at 30hz, and I thought that maybe simply cutting it off would allow me to play louder with more percieved bass when boosting the 60hz. If I just keep the bass at 0, while lowering the rest of the spectrum, wouldnt that be just lowering the volume? Personally(no offense), I dont really care how audiophile this setup would be since its only music(as long as it sounds good to me, I am happy). I do care, however, if it is a movie, which is why I listen to movies flat.

p.s. I would also like to mention that some songs(not necessarily bass-heavy songs) play with the bass sounding very...strange(such as nick cannon's gigolo). That is why I am considering on cutting off the 30hz

 

[Wodgy]

Quote:

Originally Posted by nobb If I just keep the bass at 0, while lowering the rest of the spectrum, wouldnt that be just lowering the volume?

Yes, that's right. ooheadsoo was confusing software clipping with amplifier clipping. Depending on what playback software you use, if you boost one frequency you may get software clipping unless you do something else (in Foobar, the preamp slider is specifically designed to solve this). Lowering all frequencies but one is never the correct thing to do with software equalizers, because it adds multiple FIR filters into the DSP chain, rather than just one. What you were describing in your initial post sounds to me like genuine amplifier clipping. The cheap way to solve this is to EQ away the low bass and optionally boost the midbass to compensate. Of course, a better subwoofer is an even better option.

 

[ooheadsoo]

Yep wodgy, you're right, I got it confused. On that note, I've never heard a software eq not clip when boosted, then. Foobar, winamp, patchmix, some others I forget now. They all clip when I boost and hit the specified frequency full blast with an unattenuated signal generator.

What he's describing to me sounds rather more like the phase angle/group delay on his ported subwoofer going way out of whack down in the 30's with a steep slope. Very common with cheap subs in small boxes.

 

[nobb]

...I have never heard of software distortion, but I know for sure that this is amplifier distortion. What is this phase angle/group delay on ported subwoofer thing? Btw, incase anyone was wondering, I have the Altec Lansing 221(http://www.altecmm.com/product_details.asp?pID=221). And anyone who has heard this will know that at high volumes, the bass frequencies start to sound the same.

 

[JeffL]

Quote:

Originally Posted by nobb ...I have never heard of software distortion, but I know for sure that this is amplifier distortion. What is this phase angle/group delay on ported subwoofer thing? Btw, incase anyone was wondering, I have the Altec Lansing 221(http://www.altecmm.com/product_details.asp?pID=221). And anyone who has heard this will know that at high volumes, the bass frequencies start to sound the same.

If the amp is analogue, and it most likely is, then it won't clip or shouldn't distort at +10db. HOWEVER, in the digital realm, there is no headroom above +0db relatively speaking. If you EQ in Foobar (for example) +10dB in 60hz, and the output goes above 0db, the source will clip (your sound card). In order to compensate for this, you turn down the gain so the output doesn't exceed 0db @ clipping. If you used an analogue EQ, this isn't a problem, assuming (again) the amp is also analogue.

However, I would guess that it is also highly likely that given your setup, your not only clipping your source with a 10db increase in the bass, but your overdriving (clipping) your amp, AND the subwoofer.

Turn it down, or get better speakers.