How Do Subsonic Sounds Eat Up Headroom?

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Robertt8

Robertt8

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How can inaudible sounds eat up headroom? What is the theory behind this. I mean, I know there are a wide range of sounds that that human ear can't hear. Is this what's happening? If so, If you can't hear them, why would this make your (or my in this case) mixes sound bass heavy on some systems? What's going on here?
 
subsonic sounds eat up head room cause it takes more power to produce lower soundwaves than it does higher sound waves...how many people do you hear of that blow their tweeter...people usually blow the woofer or subwoofer. you mixes probably sound bass heavy cause they are.....blue bear has a column on different sonic ranges and yours are probably around 200hz for the better part of the mix i bet....http://www3.sympatico.ca/bvaleria/bluebear/articles/mixing101.htm read up
 
and another thing!

it may sound bass heavy on some systems cause of the subwoofer setting. i dont know if you were trying it on subwoofer systems
 
I don't think inaudible sounds effect headroom much, unless you have extremely sensitive equiptment.If it was a problem, then I would think that they would make eqs that went lower than 20hz so you could filter it out.It's not the frequencies you can't hear that make you mixes bassy, it's the very low end of what you can hear, 120hz and lower.Alot of people roll off everything below 40 or 50 hz., the frequencies where rumble exists.Your mixes probably sound bassier on some systems because, some systems have better frequency ranges than others.
 
hmmmmm....

Hey Distorteddrumble, thanks for responding. It still doesn't make sense to me though. I would think any semi-decent stereo should be able to produce enough "power" to crank out the bass as well as the high end. I don't think it's tied into the speakers is it? I thought it was some kind of build up of inaudible subsonic sounds or something...doesn't really make much sense to me. I've seen that Blue Bear article before, but that's just generic EQ chart, it really doesn't explain the subsonic issues.

GRINDER: I've just read and people are pointing to my own bass problems as being this subsonic thing...don't know...
 
distortedrumble said:
subsonic sounds eat up head room cause it takes more power to produce lower soundwaves than it does higher sound waves...how many people do you hear of that blow their tweeter...people usually blow the woofer or subwoofer. you mixes probably sound bass heavy cause they are.....blue bear has a column on different sonic ranges and yours are probably around 200hz for the better part of the mix i bet....http://www3.sympatico.ca/bvaleria/bluebear/articles/mixing101.htm read up
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By subsonic, do you mean below then threshold of hearing(20hz)?You would need specalized mics to pickup those frequencies.Most speakers can only reproduce down to 20hz.Would consumer grade recording equiptment be sensitive enough to record sounds below 20hz, even with a specialized mic?If so then it would eat up headroom.
 
We're probably talking about differant things.Bass frequencies can build up when you don't roll off lowend on instruments that don't need the low end.For example,I usually roll off electric guitar below 200hz or so depending on what else is in the mix.In the 20hz to 20khz spectrum, all the instruments need their own nitch to fit in.I even roll off the very low end of bass guitar, the audible frequencies where rumble exists because, that will eat up headroom and muddy up the mix.I usually roll off or shelf everything below 40 or 50hz.
 
..........

sub sonic or subsonic LOL subwoofer sonic levels and subsonic levels that you cant hear......ok i was throwing both meanings in there..my bad....i was in the middle of looking up a new car system
 
There are 2 issues here....

Low frequencies take a lot of power to reproduce, so they are taxing on an amplifier - if the amplfier cannot suuply an adequate amount of power, it will distort.

The other issue has to do with headroom in a mix. All gear has a finite amount of "dB space" within which to work. Again, low-frequencies (subsonic or not -- subsonic freqs take up even more than audible ones!) take up a lot of the headroom in being heard and reproduced, so if many dBs are lost to unwanted low-frequencies, that's less headroom available for the frequencies you DO want. In addition, a mix overburdened with low-end will NEVER be as loud as a more frequency-balanced mix (because the low-end is sucking away precious dB space from the available headroom, the frequency-weighted value of apparent will limit how loud one perceives the mix to be.
 
Listen to Blue Bear Sound on this... Besides, that bastard has one bad ass facility! What a lucky punk. YOU feelin' lucky punk??? ;)

[In case you didn't catch it, I'm jealous!]

Need a studio parther? :D ...If only he was joking...
 
yeah, Blue Bear's the man!

So...with all that in mind, how do you know where to lop off the low end or high end for that matter (does getting rid of unused high end help too?) of certain instruments? Chrisharris pointed me to a link that provided this interesting advice...

1. Set EVERY channel eq to ditch 6 dB one octave wide at 315 hz

2. Run a hi pass filter up each and every channel till you HEAR it changing something, then back it off a tiny bit

3. Run a lowpass filter down each and every channel until you HEAR it changing something then back it off a tiny bit

4. Sweep the eq that you set to 315hz of each track down to about 180hz and up to about 450hz

...I mean, is there a list of things that can generally be used on certain instruments? Like you shouldn't need some low end of guitar if you've got a bass or something like that. Also, Should you just lop off some low end, or just turn it down a few dbs?

By the way, thanks for the help people!
 
I use a lo-cut often on tracks that really need no deep low-end... you kinda have to play it by ear....

RE -- I could certainly use an investment partner, if you're offering! ;) :D
 
Hey there, Robert...

This list is something that I got off of this site at some point. I apologize, I don't remember when or where it came from. It's just a guide, for sure, but it's something, nonetheless.

Kick: 30-80hz
Snare: 80-200hz
Toms: 70-100hz
Overheads: 40-200hz
Bass: 30-70hz
Guitars: 80-120hz
Keyboards/Synths: 30-150hz
Vocals: 70-200hz
Horns: 100-200hz
Full Mix: 20-40hz

If there is something glarringly wrong with this list, please feel free to point it out. ;) All I did was cut and paste, so please don't shoot the messenger. Hopefully I'm not doing more harm than good here.

On a totally side note, Bruce, if you happen by this thread again, just wanted to let you know that I checked out your new set up that you have, and it looks awesome. I would even go as far as to say that it might be a decent step above the blankets draped in my bedroom closet set up that I use right now.

MIGHT be.

Also, hopefully you're open to a bit of constructive crit, Bruce. I've always liked your site, but, the news portion on the first page...man, that bright blue gave me a headache. ;) You might want to adjust that a little bit.
 
Speedy VonTrapp said:
....the news portion on the first page...man, that bright blue gave me a headache...
Click to expand...
I tried a few combinations, but the one that's there doesn't look too bright on any of my monitors.... I had it as white text before and that seemed to have too little contrast on the blue...
 
Hey Speedy Thanks! I'm assuming that the list is the areas you can cut on each instrument. Does that chart look about right to you other folks?
 
Robertt8 said:
Hey Speedy Thanks! I'm assuming that the list is the areas you can cut on each instrument. Does that chart look about right to you other folks?
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I wish I knew and could help. LOL

I want to start learning Freqs myself. Actually I have been wanting to learn then for about 6 years now.

I do it all by ear FWIW.

It surely makes a hell of a difference with how the mix sounds.


Malcolm
 
Hey Speedy Thanks! I'm assuming that the list is the areas you can cut on each instrument. Does that chart look about right to you other folks?
Click to expand...

Actually, I believe it's just the opposite. I think the list is the range that a particular instrument would normally sit. (Obviously, the instrument will vary, so this should just be a loose guide, I'm guessing.)

So, you would not want to just cut 70-200 on the vocal track, see?

Pretty much anything, (again, with exception on who you are recording,) under 70 on the vocal track, is probably just making other tracks that utilize sub 70hz fight harder for their space, so you could roll off 60 and below on the vocals.

Once again, I'd assume this to be a basic guide type of a setup only. Check it out with your tracks, and use the list for a starting point, and it will almost certainly vary on every recording, but you'll have a starting reference point, at least, and that's a big help. But, it's all up to you, in th end.

After all, if the machine and numbers could do it alone, your ears wouldn't be worth anything, and you could just cut certain freq's on certain tracks, and adjust whatever the math says, and every mix would come out perfect. ;)

Well, that's the way that I do mine, anyway... :p

Bruce, I should have known better. At work, I'm chained to a UNIX box with a horrible browser, and it can't even do java right, I'm sure the problem is on my end more than yours. Sorry if it sounded like complaining. ;) I'll check it out once I get home, and all will probably be good there.

-Speedy
 
Hmm...

Kick: 30-80hz
Snare: 80-200hz
Toms: 70-100hz
Overheads: 40-200hz
Bass: 30-70hz
Guitars: 80-120hz
Keyboards/Synths: 30-150hz
Vocals: 70-200hz
Horns: 100-200hz
Full Mix: 20-40hz

Full Mix: 20-40? I mean this sounds more like a cut list. These are all the extreme lows of each instrument...unless I'm crazy here...which is possible.

I think the reason I need all this extra help is because I'm kind of shooting in the dark without monitors. Sadly, I'm in a cramped San Francisco apartment with a roommate, so I've been mixing with headphones (gasp!), so I'm kind of mixing in the dark so to speak, but at the moment it's all I can do.

Now for damage control. I'm guessing that I'm better off re-mixing and eqing each track separately than just eqing the final mix. huh?
 
Ya know...

I knew that would come back to bite me. I was hoping someone like Bruce would be able to point out the flaw in that list. That over all mix for 20-40 is suspect to me, also. I would have left it off, because it doesn't make sense to me.

The most possible scenario here, is that I probably shouldn't be offering any help to anybody here, yet. hehe

I'm just trying to remember what I've seen/heard here, and hopefully I don't steer someone in the wrong direction.

But, from what I have learned, I would say that after re-viewing my list, you are correct, and those are all fairly low.

I've also learned that I would, indeed, as you suggested EQ each instrument separately.

Now, if we can just find a high end list for that rolloff, we'll have a much better guide than what I thought I had originally posted.

Bruce, if you, or anybody else out there with the major experience under your belt could straighten me out on this, I'm sure more than just myself and Robert would appreciate it. ;)

-Speedy
 
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