Understanding Low Cut and Linear Phase EQ readings

[workman]

On the Out 1-2 of the track I'm mixing, I have a low cut EQ set at 51 hz, and then a linear phase equ also shelved off at 50 hz.

However when I analyze the post -eq frequencies (in the linear phase eq), there is still a lot showing below 51 hz.

 

Why is this? I'm sure my understanding of how these eq tools work isn't quite what it should be - but I'm puzzled by why frequencies would be showing up below 50 hz when I effectively have two plug ins that should be filtering them out?

 

If anyone can help me understand I'd be grateful.

 

Thanks!

[fader8]

I'd suggest you do some reading up on filters and how they operate. How much a filter attenuates its desired stopband is dependent on its number of poles, the type of filter it is, eg butterworth, bessel, elliptic, etc., which characterizes the shape at the rolloff point.

 

But you should never have the expectation that a filter "removes" signal above or below its cutoff, as lo and hi cut filters are designed to just reduce signal.

[workman]

I will do some reading. I hope my post didn't make it seem like I'm lazy - along with my full time job, production has been a steep learning curve for me and I've done a mountain of reading along the way. Any "pointers" are always helpful, so thanks for your post, fader8.

[fader8]

I will do some reading. I hope my post didn't make it seem like I'm lazy -

Not at all. It's a fair question to ask when you're starting out on this stuff. While filtering can be a very complex subject, the basics are not, so any decent book about audio craft or even various websites should get you a sufficient working knowledge.