PEQ Preamp Filter Question

[Factolermentation]

I have just recently gotten Equalizer Apo set up on my PC as I previously have mostly used Wavelet on my phone for headphone listening. I'm using a PEQ filter set found here.

I noticed pretty much all of these have preamp filters around -6.0 db. I was just curious if, say, my headphones aren't capable of being driven as loud as I'd like, if it were theoretically possible to add some sort of scalar quantity to that preamp filter and then each subsequent filter band. I guess in my mind if I'm globally reducing volume and then EQ-ing certain frequency bands up or down, couldn't I just...shift the whole thing up a db or two? Or am I just wrong on what's happening at a fundamental level with PEQ?

This is purely theoretical and just time trying to understand what PEQ is actually doing. In reality I'll be purchasing probably an Atom+ or the Topping equivalent soon.

You are all great; my headphone listening is experience has vastly improved since I have become an ASR member.

 

[MRC01]

With digital, full scale is as loud as it gets. There is no headroom. If you amplify it further it clips. Assume the original musical content peaks are near full scale. If you have a PEQ that increases any frequency, then it could clip. So to guarantee no clipping, lower the entire signal by an amount equal to the biggest PEQ boost. If you have multiple PEQ bands and they overlap, you need to sum them for combined effect.

Now you may be able to get away with less lowering than this because with most music, most of the amplitude is in the bass. Suppose you have a PEQ that boosts a center frequency of 4 kHz by 6 dB. Even if the total musical signal is louder than -6 dB, the portion of that total signal at 4 kHz is at a much lower level. So this PEQ filter would be unlikely to cause clipping when playing most music. Of course, if you played a frequency sweep at -5 dB, it would clip passing through 4 kHz.

Also keep in mind most modern music is EQed and dynamically compressed like crazy. The spectrum and loudness can look like a brick wall. It's already clipping, or nearly so, before you apply any processing. My comments above refer to well recorded, uncompressed, natural music.

Note: I don't recommend anyone reduce the overall signal less than the "safe" amount. There should be no reason to. Most headphone amps have enough gain to lose 12 dB and still drive headphones to ear-shattering levels.

 

[Factolermentation]

With digital, full scale is as loud as it gets. There is no headroom. If you amplify it further it clips. Assume the original musical content peaks are near full scale. If you have a PEQ that increases any frequency, then it could clip. So to guarantee no clipping, lower the entire signal by an amount equal to the biggest PEQ boost. If you have multiple PEQ bands and they overlap, you need to sum them for combined effect.

Now you may be able to get away with less lowering than this because with most music, most of the amplitude is in the bass. Suppose you have a PEQ that boosts a center frequency of 4 kHz by 6 dB. Even if the total musical signal is louder than -6 dB, the portion of that total signal at 4 kHz is at a much lower level. So this PEQ filter would be unlikely to cause clipping when playing most music. Of course, if you played a frequency sweep at -5 dB, it would clip passing through 4 kHz.

Also keep in mind most modern music is EQed and dynamically compressed like crazy. The spectrum and loudness can look like a brick wall. It's already clipping, or nearly so, before you apply any processing. My comments above refer to well recorded, uncompressed, natural music.

Note: I don't recommend anyone reduce the overall signal less than the "safe" amount. There should be no reason so. Most headphone amps have enough gain to lose 12 dB and still drive headphones to ear-shattering levels.

Perfectly explained, thank you!