Ok i have the asus maximus formula motherboard, and i use the sound card that comes along with it which supports 5.1 audio. Anyways so i hooked the logitech z-5500 speakers up and they dont seem to go loud enough... compared to my old Altec Lansing speakers these do not go loud at all... now what is causing this, is it the speakers themselves or the soundcard?? By the way its loud... but not that loud.. if you know what i mean...
the volume is controlled by the amp in the speakers, although thw levels of you settings in windows obviously affect it.
however, you may be confusing loudness with volume, cheaper speakers sound loud due to all the distortion and noise that accompanies the sound, they may sound loud to your ears but that does not mean they have alot of volume if you get what i mean.
it could also be that your old altec lansings(which model) had a higher gain amp which could put out more sound. what was the max decibel output of both speakers.