For some that may sound like a scenario to get to, but actually it is a problem for me.

So I had a chance to borrow my fathers car. The car has quiet a nice sound system for a normal car, very rich and present sub basses. I would love to tell you what the specs are, but I couldnt find out. Dont even know how many speakers there are, how big the woofers are... Only that it's a Dolby Srurround Pro Logic II sound system.

I took the canche to listen to some of my own music, as well as some other music of the same genre, to see how music does in my fathers car, and how it sounds compared to other tracks. My basses are cool, but two of my tracks let the car shake. Sounded like metal shaking against metal or something, I dont know... Like it sounds when you listen loud music in old, used, little shitty car with an old, used, little shitty sound system. And the car sounds like it would fall apart any minute. So not healthy.
I hadnt experienced that before, with no of my 3 souund systems, nor in my car, or with any headphone.

So what could have caused that? Is there some hidden secret about sub basses I dont know of? I mean something have to went wrong, otherwise the bass would have rumbled and vibrated normally.

 

harmonics?

edit:resonance

 

This is called resonance - every object has 1 or more resonant frequencies. All it means is that the bass frequency in your track happens to match the resonant frequency of an object in your car, and it causes the object to resonate and make a noise when that frequency is played.

 

Really? I dont know... From all the tracks I made a track finding the resonant frequency? Twice?

Yeah thats actually what came to my mind, but subjective I think the basses werent that big, I know and heard tracks with bigger basses. Then again Im afraid people might know better ways to make a bass fat without toachign the limits?

 

that's what I was thinking, used wrong word (suffering from man-flu)

 

I would say - Yeah, resonance. It's a physical thing. Trunks have them. Speakers have them (read up on bass reflex ports). Even rooms have them and they are then called standing waves ("sweep" with your voice while you are in the bath/shower singing, and you will hear some very specific note(s) will be resonating very loud).

Maybe, just maybe, your dad has a bass boost setting, which boosts certain frequencies (which might happen to be in the trouble area).

Tighten/secure/foam everything metal that might be moving/resonating (over here we have the vibrating licence plates going Ummfffpfrfp-ummfppprpspp on the outside of the young'uns cars).

 

Well it's certainly possible, all sorts of things resonate. The main thing to do would be to find out where the noise is coming from.. is it a panel or something?

The other thing it could be is a decoupling of the speaker from the box. This happens when infrasonic frequencies go unfiltered through a bass reflex box. A bass reflex box is tuned to a frequency and will work well at that frequency and above. But anything lower can actually damage the loudspeaker, the effect is called decoupling and can sound like a harsh knocking sort of noise.

It's hard to explain, but if the sound is coming from the subwoofer, try highpassing your track at 20hz. Or the bass amp may have an infrasonic filter, they're on most good bass amps and are designed specifically to prevent this.

 

The deep bass is some of the hardest to mix because it is often more felt than heard and requires a properly setup room/monitors or at least a good understanding of the rooms resonances to mix properly. Make sure you are high passing most of ur tracks. This becomes especially important if your using any of your own live recorded sounds as your mics will often pick up a a lot of low end rumble, ac, foot stomp, etc that can sneak into the low end. My guess is your speakers/sub went crazy because they were overloaded by ultra-low frequencies between 10-50 hz which you never realized on your other systems because they weren't able to replicate that low end properly.

My guess is that most mix engineers would say if there was a hidden secret to sub basses is to use sub bass plugins sparingly and make sure you're listening in an environment and with speakers that can properly replicate those frequencies equally.

Things to try-
1. High Pass all tracks xcept possibly bass and kick. Crank up the filter until you feel the track start to lose a bit of weight and then dial it back a little. Also try this on your bass and kick even if its only at 20-40hz.

2. play a similar "reference" track in the same genre of music and the same key as your songs you'r having problems with in your fathers car and see if they suffer the same problem. all cars tend to have low resonances but most professionally mixed/mastered songs are careful to have tight control over the low frequencies to avoid over-emphasising this.

3. If only certain bass notes stick out try using a multiband compresser on the low end to even out the variances.

4. If none of these solve your problem, Rip out your subwoofer cord from under the dashboard and make loud "Boom Boom" noises and stomp your feet whenever there is a kick drum or bass note.

Let me know if this helps

Jeff

 

Excellent topic and some great info shared.

@VirtualMark - when you noted "every object has 1 or more resonant frequencies" ... that I think is the key....

TO creating music that could actually physically affect surroundings... more than just bass thump... we could theoretically create songs to level buildings...

Talk about COMBAT ROCK !

How about a directional megaphone used to simply open doors... WOW !


How about a war fought using EDM !!!??

Nice... got my mind working overtime now !

 

Yeah I can imagine it, one site is dancing all night, the other site is getting completly destroyed
Sounds like something for a weird japanese manga...

 

well it's all dependent on the type of bassline you made for each track.

It's actually quite simple. Some of your tracks may have had a bassline with relatively lower subs, and the other two tracks had some subharmonic frequencies in them that were very subtle, but only able to be brought out with a larger system. Subs usually are the reason for why your car shakes, and surround sound takes advantage over them more than in any other system.

This is where multiband compression becomes very important in mastering, it compresses the basslines so you get consistent bass dynamics in all your tracks. So no matter what bassline you create, the sound that you will hear from them, whether it shakes the system or stays normal, will feel and sound the way it's meant to.

 

This is usually caused by a loose license plate or something loose in the trunk. If you don't want that rattle tighten those things up or put some spongy stuff behind the license plate so it doesn't hit the car when shaking. No one wants to hear a crappy tin can rattle out of a car, so fix it up!

 

Well cause of my bad english i have to keep it simple.

You said it only happens on some soundgear like subwoofers & similar speaker that provide or add a high subbass right.?
So let us try to handle it with a little mastering trick that is used to make your low end ready for Vinyl. (don´t hang my up at my explanation i know it´s not completely right but.. only to get you in my mind)

So first ... keep every track like it is ...
+At the end of your Mixing/Mastering Chain... Try a plugin like the elephant limiter witch provide the "DC-Filter" function...



Play with that knob, raise it up till the point you "feel" you lowend and your Kick looses fullness & thumb... Go back to that point you don´t realise that loss. BANG. done. Bounce your track again and take a listen... Maybe thats all you need to do to handle your lowend without loosing that dynamics you created..

No need to use dither or limiter function of that plugin, every plugin witch deserves that DC-filter funtion will do that job i guess..

peace

 

Thanks n12n0, I will defiently try that out soon *yes*

 

After you've high passed all the tracks, also high pass the master. a good starting point is to cut off everything below 40hz - and if you have an EQ capable of M/S, cut off the side channels below 125hz (thus leaving the bass mono)