well from the info we have, anything could have happened to that sub over 7 years, degradation to the wires in the voice coil maybe, rust in the voice coil......
I just dont think you can compare a 7 year old sub with a new one and expect them to sound like you do even with different power ratings
6 or 7 years ago was before something called "CEA2006" power ratings. it was common for amplifiers to be rated higher than their actual output. if the older amp was 15 years old, it would likely be louder than the new one, for different but similar reasons.
distortion, in technical terms, is the difference between the sound going into the amp, and the sound coming out. In simple terms, it's when you tun it up loud and the sound goes fuzzy or breaks up.
MacMini in an Alfa? - Why not!
BTW, Thanks everyone for your input
i think the key is the input sensitivity! for example, You have a 2Vrms line output from the soundcard, the 50W amp has 2Vrms line input and the 200W amp has 4Vrms line input. the result is that You need 2x high gain level on 200W amp to reach the same loudness! but if You have a matching output, this amp will kick the other! of course the smaller one will be distorted because of too high output level...
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