Gamma1734 But sometimes I'm thinking of boosting the highs, especially the area near nyquist, to give more sparkle to pianos that sound a "bit dead". The problem clearly is, that we will drag the recording noises and other noises out a lot by that, but that's sometimes a price that I'm willing to pay.
I imagine that the reason you're accentuating noise is that there's just not much signal at those frequencies. But first let me give some context so others can understand.
We humans hear in the range 20-20,000 Hz. and the highest C on a piano is only 4186 Hz at it's fundamental frequency. All of the upper frequencies you hear above the fundamental frequency are harmonics, and much of the character of a piano is in the loudness/behavior of those harmonics (and other instruments for that matter).
Around 1960, Neumann released the U87 microphone - and this was basically the dawn of hi-fi recording. Ever since then, almost all Large Diaphragm Condensor mics (LDC) are clones of the U87, and our entire planet is used to hearing recordings with the U87 characteristic. The frequency response basically looks like this:
You will notice the bump at 10000 Hz. That bump is known colloquially as "air", and recording engineers use that bump, especially with vocals, to accentuate the upper harmonics in one way or another. The newest version of one of my mic-preamps even has a "air" button that boosts these frequencies automatically.
You can do the same with EQ. if you're talking about accentuating near the Nyquist frequency, which for my 48khz samples is around 24Khz, that's extremely high I think - above human hearing. So you're boosting alot of noise.
I use Fabfilter to audition EQ changes and mess around with the sound, but then I apply the EQ to the raw samples instead of using the EQ in realtime. Fabfilter, and others, have both a EQ curve and spectral analyzer. Below is a picture of the second highest C of my Steinway library, played at fff, with the pedal down:
You can see the peaks, around 2.1Khz, 4.2Khz, 6.5khz, up to about 14.4 Khz, and tiny one at 19Khz. Beneath that, you can see a bunch of noise, and obviously because the peaks are smaller to the right, the signal to noise ratio is horrible.
So my suggestion is to use EQ below/around 10k to accentuate the piano harmonics. Too high above 10k, you either won't hear it or the signal will be too noisy. Unless you're using a purely synthetic piano like PTQ.
Gamma1734 Maybe you have heard of Airwindows,
I've heard of him, but haven't tried the plugins yet. I'll check it out. He sounds more hardcore than me...