I had the misfortune of blowing my CX115 speaker. I was using a 350W amp, and this speaker handles 300W... So I've sent my cab to Thomann and they've replaced the original speaker with this
The sound is deep and defined. It is not too bright, and delivers good punch. I believe it is a paper cone speaker, and is warmer and softer than the aluminium ones. The CX115 cab where I'll use this speaker has a horn, too, with compensates a little on the highs. I consider the GK's as in-between sounding speakers, compared to, say, vintage Ampeg sounds and modern Hartke sounds.
If you keep in the 300W 8Ohms limit, it is powerful enough for small to mid-sized gigs. If you intend to use it on stage of bigger venues, you would probably need a second cab or some reinforcement from the PA. system.
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