Have you guys ever encountered a resonant frequency that you cannot pinpoint? There is one in a track I am mastering that is simply bothersome, yet I cannot find it even with spectral analyzers. Could it possibly be a resonant transient that seems a lot more prevalent in the mix? How would you guys suggest dealing with this?
I get this from time to time when I'm mixing, most often in harmonically-dense instruments like distorted guitars, pianos, etc.
Rather than boosting with a narrow Q and sweeping around for it, try cutting with a fairly wide Q, sweeping till it goes away, then narrow the Q and sweep some more, back and forth, while you continue to narrow the Q. Eventually, you'll hone in on it and can set the appropriate amount of cut and Q.