An EQ question

[gcjammin1]

When doing mixdowns, I've heard of using a spectum analyzer. What is this and how does it work. Is there a tool that you can use that lets you know when you mixes are flat or is this the tool?

Gcjammin1

[elsteve9]

A spectrum analyzer simply shows you the frequency response of your music, or sound.

A hardware spectrum analyzer usually looks like a 31 band eq, axcept instead of those handy faders, it's got rows of LED's, like on a mixer. Except it has 31 rows. (Right? One row of lights to take the place of every fader.)
ANyway. It listens to the sound, and allows you to see if you have a ton of say, the stuff around 300hz.
It's used alot in live sound to tune a PA to a room, but to be honest...I've tried using it on my mixes, or my feeble attempts at mastering, and if it can be useful, I haven't figured it out yet.

But they're cool to look at, if you ever get an opportunity.


-Stephen

[atma]

most software audio editors that i know of have a basic spectrum analyser that you can use in real time or to form a composite of the entire track's frequency response. some of my friends swear by using them, though i only refer to them occasionally for certain things.

an interesting thing to try, if you want to hear what "flat" sounds like in the context of the mix you're working on is to use some kind of convolution EQ, like steinberg's freefilter (there's a few others as well). feed it a sample of pink noise (a "flat" logarithmic frequency response), then feed it your track and let it learn its EQ. then you can apply the freq. response of the pink noise to your track.... a theoretically interesting trick, but more often times than not, you don't really want a totally 'flat' response. in a lot of cases if your mix doesn't have much happening in the ultra high frequency range, the convolution eq is going to crank up those frequencies (read: crunchy hiss galore) that aren't really there to begin with.

i do use that trick in moderation sometimes with individual samples or instruments on occasion if they really need to be flattened out. its kind of a hit or miss process.. anyhow, i digress!

[djui5]

Spectrum analiziers are quite usefull to many engineers in the mixing stage and is another tool that don't have to be used but can be used. I find them very helpfull in finding frequencies that are poking out or finding frequencies that are too low. What the device does is (in laymens terms) show you how loud each frequency is across the whole spectrum (20HZ-20KHZ). Yes..most of them show the same frequencies that a 31 band graphic eq has. I like them. It's interesting to take a cd that really inspires you...a cd that you love the sound of, and see what it look likes on the analizer, then pull up your mix and compare them. I'd recommend finding a plug-in version or a hardware version and giving it a test drive. I'll bet it helps your mixes quite a lot and if anything it's fun to play with.

[gcjammin1]

Thanks for all the replies. The bass frequencies are usually my problem. I was wondering along the lines of what Randy said. Do you have a plug-in or hardware analyser that you would recommend? I think it would help alot to be able to compare good mixes with mine to see where everything falls on the spectrum.

[elsteve9]

What DAW program do you use?


-Stephen

[gcjammin1]

Cakewalk 9 and Sound Forge 4.5

[djui5]

http://www.brainspawn.com/products/SpectR2/

You can download a demo that will work for 3 minute's, or if you wish you can purchase it for $35. I tried to find a free one but to no avail. I'm sure there's one out there somewhere.

Also try http://www.thedirectxfiles.com/plugins.htm

I assumed you're using windows 98 or greater.

[gcjammin1]

Thanks alot Randy. I'm using windows 98SE.

[djui5]

good guess!

[atma]

or just use the one that's in soundforge...? tools>spectrum analysis

you can select the whole file and have it create an overall response for you, or you can run it real time.

try running pink noise through it first though, then you can see what "flat" actually looks like (doesn't actually look horizontally flat as you might expect)

[gcjammin1]

Atma,
Do you record some pink noise and run the spectrum analyzer on that?

[atma]

ya, unfortunately you can't really synthesize pink noise with soundforge (in wavelab you can, however), but i did a quick search of google and found some audio test files, so if you just download this and extract it, you'll have a wav file of pink noise. so just select the whole file and then run the analysis on it and you should be set!


http://www.dogstar.dantimax.dk/testwavs/pink.zip

[djui5]

Does the spectrum analizer in Sound Forge have a graphic version? I remember it being a thermal display..but I haven't used that program in a long time.

[atma]

ya, its graphical, the one in wavelab has the 'thermal' display.

[djui5]

ahh...cool. Thanks!

[Sinkharmony]

Does anyone know of a Spectrum Analyser for Pro Tools? Something that's RTAS and Native preferably. I've been trying to find one that isn't too expensive and I haven't had much luck.

[djui5]

let me look and I'll post a link later today.

[gcjammin1]

atma,
Thanks for the help and the link.

[Sinkharmony]

I appreciate any help