Ambipoly has a fantastic response in the high register on the Bass Clarinet! I am really impressed!!! I got the #3 but I should have gotten the 2,5+, but I didn‘t return the product. The middle and low register sound dull but the company suggests to adjust the reed with a knife. They even very precisely specify on which part of the reed the adjustments should be done, thing which I did and, in all honesty, it worked pretty well. Don‘t worry the reed will look awkward but it won‘t disturb your playing. I‘ll definitely buy a 2,5 or 2,5+ soon.