Wednesday, January 11, 2012

The Ideal iTunes equalizer settings

I was nerding out audiophile-style tonight, and came across this discussion of optimal iTunes equalizer settings. Buried in the comments section, an audio engineer discussed the benefits of "subtractive filtering". I followed his advice and was definitely pleased with the results. Try it for yourself - but remember, what sounds good to you is ultimately what's most important. If you have the prowess, here's a handy Applescript you can run to create the settings.

The comment of note:

As an audio engineer and producer with 18 years of experience in the field working in some of the 'finest studios in the world', I'm confident in saying that this approach is backwards.

Equalizers in both the analog and digital realm do subtractive filtering far better than additive filtering. When pulling the EQ down you are not creating the additive comb-filtering necessary to boost frequencies that do not already exist, so using this kind of approach is leaves more of the original audio intact and does not add as many artifacts to the signal.

Of course an FFT digital EQ can overcome this (which is why the Weiss products are so expensive but popular), but iTunes most certainly does not hog the processor by using FFT algorithms for it's EQ.

What would be more appropriate, and also avoid unnecessary distortion, is to do all of those adjustments subtractively, then making up the gain difference with the slider at the left. This is why the slider on the left exists, in case you were wondering.

Like this (-8, -5, -2, -4, -5, -6, -4, -2, 0, -3), if my math is correct. Then just boost the overall gain at the left to make up the difference.

I'm not suggesting this will sound "better" to you, but it will certainly be a cleaner way to use the EQ.

Phil Spector probably has a better idea of the ideal EQ settings.