Thank you Simon. All my 4 x 10 cabs and 8 x 8 and 8 x 10 fridges all have tweeters. I do not use any bass cabs without tweeters as the tweeters help cut thru the bottom end to give clarity to the bottom end tone that the bass produces. Otherwise the bass sound will be too muddy for my liking. I also have a 12, 15 and 18 inch cabs i use as well.