Here is my Orion 5 Band Parametric Equalizer after heavy mod. All caps were optimized the best on their category range, electrolytic for low range, MKM for midrange, and very low ESR caps for high range. In fact, each caps were pre-selected by measuring the closest nearest value between left and right channel using LCR Meter. But choosing, sorting out and testing the result from so many capacitor brands and type with limitted budget is quite challenging.