Are you talking about Fletcher Munson curves or ???

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X shows frequency , y dB ( think sound pressure)

The curve delineates what is perceived as the same loudness despite having very different actual intensities.

The reason there are more than one is that given the range of intensity, the ear acts differently.

All you really need to know is your ear is more sensitive to mid highs 3-4 kHz, listening loud tends to distort the function due to the natural compression of the ear by tightening the cartilage or whatever is attached to your 3 bones in the ear I can't remember.

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Yep, 5 points to Richie.

It's Frequency in Hz over DB as SPL.

Fletcher Munson is the old standard and name, they have been replaced with the far less sexy ISO 226:2003 curves (which basically took all the existing studies and compiled them in to more accurate curves).

Bear in mind that these curves relate to pure tones (sine) at different frequencies and how they are relatively perceived to our ears.

You really don't need to "apply" anything as such, just understand that frequencies are perceived differently in terms of volume.

For the revised curves:

But by all means don't start EQ'ing towards these curves as you end up with harsch earpiercing brittle tracks.
Learnings can be spades of headroom to be found by rolling off high en low ends
However again no standard recipy, but experimenting with freq and steepness of filters on track by track basis. Also note that doing this with 6" monitors in your untreated bedroom full of standing waves and reflections, is not the best place to experiment with this. Neither are headphones.

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Its important to understand all of the above if you are want your music to be upfront and clear i.e. loud
No amount of squashing with a limiter or ozone will make your track appear to be loud if you dont have a proper midrange in your track...

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quote:

Originally posted by Raphie But by all means don't start EQ'ing towards these curves as you end up with harsch earpiercing brittle tracks. Learnings can be spades of headroom to be found by rolling off high en low ends However again no standard recipy, but experimenting with freq and steepness of filters on track by track basis. Also note that doing this with 6" monitors in your untreated bedroom full of standing waves and reflections, is not the best place to experiment with this. Neither are headphones.

quote:

Originally posted by evo8 Its important to understand all of the above if you are want your music to be upfront and clear i.e. loud No amount of squashing with a limiter or ozone will make your track appear to be loud if you dont have a proper midrange in your track...

These are both on the money.

Lovehate - basically ignore the curves in terms of making music. It's really something you just need to absorb and understand, not actually apply practice to.

A few small things to take from it.

A compressor acting on full band intensity will be triggered by the bass energy which seems almost non existent.

It also shows how mixing at certain levels will change your perception.

That's about it

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"This is why Superman works alone." GC
old stuff from days gone by (2001-2004)
Mad For Brad's gay little contest