First things first: hardware can’t solve a problem if it exists in the recording itself, and things like subwoofers will bring out qualities in the audio that are hidden without them. Usually that’s a good thing (obviously, the whole point of bass boosters is to augment frequencies that can get lost without them), but sometimes it brings out flaws (such as when the bass was recorded or imprinted already dirty). So if whatever you are listening to doesn’t have a clean bass sound, no technological fix will get it for you. But it’s more likely that the issue is your setup. Low frequencies have more overtones, so it’s not easy to boost them without getting distortion unless you also change the sound in other ways. Basically, you need to do three things at once: boost the bass, reduce the treble, and apply dynamic range compression to the whole signal. That can be complicated, so I’ll PM you a link to a site that might be able to give you more specific help.