K8077 kit bass reflex tube

The subwoofer kit k8077 is really good,
the circuit works
But how long must the bass reflex tube be

sorry for my bad english

thank´s

This depends on you taste, room dimensions, position of the unit in the room, etc…
You can experiment with different settings until it sounds the way you like it to sound.
Next, you can glue it to fix the lenght.

ok

thank´s

youtube.com/watch?v=MOIJMmxLCdw

This is my little project, and my question is : how much will reflex pipe improve bass on this box, and may I put her on the side, like in this picture? And what dimensions would it be?

thx in advance!!