hi,when i export a project to an audio file for mastering,i have the master fader at -5dB. I was going through a feature on mixing and it said to leave 3-5 dB of headroom. Is that what im doing by having the fader at-5dB.
I read a part about -8db RMS. What does that mean?
i know this is basic stuff,but i want to get an understanding of it.
thanks.
No what you’ re doing is having the fader at -5 dB. Leaving 3-5 dB of headroom is mixing to so that the loudest level is at -3 to -5 dB FS
RMS means root mean square. And means the way how the level is measured (Peak level, RMS level…)
so i shuld keep the master fader at zero then? and just keep an eye on the meter?
how do i check RMS level?
Generally you can keep the master fader where ever you want to (start gain staging discussion now, please).
As long as you export to fixed point format, the post fader Peak levels should not exceed 0 dB FS (or whatever someone tells you he needs a s headroom)
RMS levels are checked with RMS level meters, like the one I can´t remember the name of at the moment.
Yes, as thinkingcap. Keep the fader at -6 to -10 as you mix and when it’s good to export then set to 0db. Otherwise you will get a reduced level product. I keep forgetting to reset to 0db for export myself maybe I ought to blame Cubase and request a “0db for export” button. 
Saying “measure RMS” doesn’t tell you much. If you have a song that starts with almost inaudible whispers for 2 minutes, then 2 minutes of jet engine, what is the RMS of that song?
There are Peek and Average readings. And there are many little details about measuring in time windows. This is a large subject and really requires some research.
There are some great FAQs on metering at this site http://www.digido.com/
But, like a lot of things, the short answer will be wrong because it will lack context. And, the context would just be confusing and possibly not relevant to your situation.
There are metering plugsins that will show you RMS readings. They have a ton of settings. The meter won’t tell you anything unless you understand what the settings mean.
if i keep at -6 or less for mixing,the turn up to zero,is thevolume level then not going to be too high?
That´s not what I said.
If you keep your fader at -6 to -10 and mix with the level meters at 0 dB FS, and later raise the fader to 0 dB for export, you´ll get overs. So keep the fader where you want, mix with the desired level and for export keep the master fader where it was while mixing.
exactly - see post above.
OK I get you. Sorry. Different styles. I start master -6 or -10 then kit or bass drum at -6 to -10 and balance everything around that. Then on export I raise the master. I tend to keep as simple as possible. Very rarely I find I need to reduce or raise levels to get the export stage I like.
I’d remind you that you already know what gain staging/control is already. The OP needs to understand why you make the decision to mix around a bass at -10 and that others may mix around a different reference (although, I also find a kick at -10 to -12 is an excellent pivot point for rock/alternative/fusion jazz type styles). He also needs to understand what -10 actually means in the digital vs analog worlds. From his questions it seems he isn’t clear about the difference between reference levels on a per track basis vs the master. Also, using the word “RMS” as an export reference is bad joojoo. Pretty meaningless.
thanks for the replies. now i need to get my head around this,so bear with me.
im making house music.(incase it helps u guys explaining)
what should i put my master fader at when mixing my track,if i want to leave 3-5dB headroom. surely setting it to zero isnt an option?
That explains a lot 
Surely setting it to zero is an option.
Headroom does not have to do anything with the master fader setting. It has to do with the signal level. You can set your master fader to 0.00 and mix your audio levels to -5 dB FS (with the channel faders) which gives you 5 dB of headroom.
On the other hand you can set the master fader to -10 and mix your levels higher than 0 dB FS (by raising the channel fader levels), which in fixed point mixdown will have your audio clipped.
And lastly, if you mix with the channel faders too high, so the signal on the master fader gets too hot, you can simply bring the master fader down, the same amount that the mixed audio is too high, so that the (post fader) level of the mixdown stays below 0 dB FS.
Generally it´s good practice to keep the master fader at 0.00 and mix so you stay below 0 dB FS with the peaks.
would u believe it i only noticed the peak meter value box about 20 mins ago!
Also, using the word “RMS” as an export reference is bad joojoo. Pretty meaningless.
Yes, which is why I made no reference to it after I read the first post. RMS is a strange bedfellow for DAWs anyway.
Root mean square is usually applied to current or amplifier use.
Still the OP seems to be getting the hang of it.
Sorry, I was simply trying to remove the word RMS from the “headroom” discussion.
Also, in a traditional rock setup the -10ish reference works as you will add instruments that will eventually push the master to an approximate -5 or 6 db. But, what about adding LOTS of instruments for say a swing band… suddenly that -10 is not correct (I know you know this). Or, say a string quartet. Artificially boosting a low number for like sounding instruments at the master is usually not going to get you what you want.
Headroom is a tricky and important concept, but there is not an “answer”.
Yes.