No Fiberglass Insulation In The Klipsch Heresy

I wonder if anyone has tried putting insulation in the Heresy's....I wonder why they don't use it ? Does anyone know ??
the heresys are a critically matched sealed box design....
Then I would assume there would be no gain to put insulation or sound deadener in them.....What about stiffening the back or sides with bracing ??? I'm not trying to make 1000.00 out of them , just any improvement I can while I have them apart . I am refinishing them and everything is out of them.....Thanks for the help...

The best improvement you can make to the Heresy or any other Klipsch speaker for that matter is to upgrade the crossover network. Upgrading the crossover network will tranform your Klipsch speaker into an entirely new speaker (for the better). I upgraded all my Klpsch crossover networks and the improvement was WAY more incredible than any IC, PC or speaker cable upgrade. You have not heard how great Klipsch speakers are until you've upgraded the crossover network.

re - upgrading the crossover network... ya, but who can do this for us? are there guys who have a pre-packaged xover for the klipsch classic series?
I still have a pair at home and i did place a 1 inch thick foam covered the inside bottom area and alas,i am getting more deeper bass.Btw be carefull not put a lot.Just try it and you will see what i am talking about.Good luck.
There are a few folks I know and are absolutely outstanding. I myself have upgrade the KLF series and some Heritage models. I can do just about any Classic crossover network also. I also do other speaker brands also like Polk etc.

Email me at if you're interested.