The sound quality of the Piranha seems quite good. I did not notice any distortion even during heavy explosions and impacts, when bass reproduction can cripple lesser speakers. The highs are crisp and the stereo positioning works well. You can tell when a sound comes from either the left or right, and there is also a discernible difference between front and rear. The volume knob offers plenty of adjustment and the microphone can be turned off easily with the flick of the switch.
Speaking of the microphone, I also tested it while playing some Team Fortress 2. I found it a little difficult to adjust the sensitivity properly. Other players had problems hearing me or could not hear me at all. What I ended up doing was cranking the volume/sensitivity of the sliders all the way up, and enabling the mic boost on both my audio card control panel and also within the game. Bass and treble control are greyed out and won't let me change those, probably because the Realtek console overrides the native Windows control. With everything maxed out I was able to carry on conversations, however it was just barely at a normal level. If I spoke quietly or adjusted any of the sliders down then other players had problems hearing me again. Unfortunately with everything cranked up, and no other sound coming through the speakers, there is a slight audible hiss from the microphone gain. Once I was in-game however and sounds were coming through the headset, the background hiss was no longer noticeable. If I tap the microphone with a finger it sounds plenty loud, so it seems the distance of the mic from the face might be causing the sound level to be low.
I found the Razer Piranha online at around $80 which seems a little high to me compared to other manufacturer's gaming headsets, almost double the cost. Yes there are a select few other brands that charge as much or more for a set of headphones, and in Razer's defense, I have not tested each of the lower cost headphones to compare the quality with the Piranha, so the old cliche "you get what you pay for" may hold true here. If you are looking for a quality gaming headset that is decently comfortable to wear for hours at a time, and offers true clear sound and pickup, then the Razer Piranha may be just the one for you. If it was my money though I think I'd take a chance on a lower cost unit from another name brand.