No bass reflex tube?

Hey all, just joined up and this is my first post, I'm pretty new with the subject of DIY audio so this may be basic/incorrect! :D
A couple of weeks ago my Dad gave me his old (80's?) stereo, its a Sharp SA-111 system, can't find any online specs or anything, and I've been doing little mods here and there to try improve the sound quality.
One thing that's been confusing me is that the speakers themselves have bass reflex holes in the cabinet, about an inch below the right side of the woofer, but no tube, and from what I've read about bass reflex is that you need the tube for it to work! So would fitting an appropriately sized tube to it help the sound?
Also the crossover to the tweaters is a 1st order crossover, would building a 2nd order crossover and replacing the former help the sound?

Cheers,
Will
 
Hi Will,

What you have is a true bass reflex. With a tube it's often referred to as ported. Adding a tube will change the tuning frequency and characteristics of the sound. If they made it as a reflex, then it may sound best the way it is.

Also the XO was supposed to be designed for the drivers so changing it might not be the best option as to do it up right, you will need to measure the T/S parameters of the drivers and do an impedance plot before you can design the new XO. A 2nd order will help a bit with the power handling though.