I just bought a TX-SR605 last night second hand to try getting my theater a bit more audio depth. Currently i have a pair of Cerwin Vega LS-12s with a CL-15 powered subwoofer. Using the old amp, a cheap 50 watt boom box or my sx1800 samsung PA I get deep powerfull sounding bass with the music. With the Tx-Sr605 though the sound is bright but lacking on the bottom end. I have tried adjusting th ebass and treble. +10 bass -6 treble. But its still not quite where i want it. Is it normal for these amps to have less bass? any solutions or possible checks i can do?