I used these speakers to replace the original Paragon speakers in my GK 1001RB 2x10 bass guitar combo. One of the original woofers in my combo ripped right off the frame, and the other was soon to follow, so I rolled the dice on these as replacements.I swapped the speakers out, turned on the amp, and was blown away by the sound. Not only were they louder than the Paragons at a lower volume setting on the amp, but they sounded better too. They have great low range for bass guitar, and can easily handle the lowest frequencies I could dish out. (I play a 5-string) Cone movement was good, with decent throws, but the cones weren't visibly tearing themselves off the frame. All in all I'm very happy so far. I'm a semi-pro musician that rehearses and gigs frequently, and I rely on this combo for both settings. These speakers have bolstered my confidence in my gear.I have given 4 stars only because I don't know how these will perform as time goes on. They are brand new right now, and will probably last a long time, but that remains to be seen. So far, so good, though...