Radio Shack MINIMUS 7 crossover upgrade


I understand there were articles talking about upgrading the crossover of these bookshelf speakers.
Where can i get more information about this discussion and how to do it?
shsu

Showing 1 response by lngbruno

A DIY company offered a upgrade kit many many years ago but basically this is what you can do:

1. Replace the stock gray capacitor with a 4.7 microfarad Solen rated at 250 volts. The old one may be hot-melt-glued to the crossover board so instead of trying to remove it, just snip the leads and solder in the new cap.

2. Remove the fiberglass insulation and affix / dampen the top, bottom and sides with a sticky dampening material (like Dynamat) since the one used is no longer available. Be carefull handling the FG. Reinsert the FG (you may want to replace the FG with some Poly).

3. Dope the woofer. It seems Damar varnish is the "dope" of choice. Damar varnish is not a brand name, but a type of varnish typicaly used by artists who paint with oils. It would be available from a local art supply store. Grumbacher's Damar Vanish (2 1/2 oz. was the smallest bottle I could find at Michael's or other artist supply store). Do not get the type used for airplanes Coat just the woofer with a small brush and be VERY CAREFUL not to get any on the rubber surround. Allow it to dry eight hours and then apply a second coat. Allow second coat to dry 24 hours before playing music. DO NOT ATTEMPT TO TREAT THE TWEETER!

[u]Special Note if you cannot find the Grumbacher Damar Varnish.[/u]
Run a test of a couple of whatever Damar varnishes you can find on 24# or higher copier paper or paper grocery bags cut into 4" square and let dry over night. The successful varnish will dry without warping the paper. Michael's was very accommodating in allowing me to return the ones I didn't use so long as I didn't gum up the containers.

You can google to see if there are other options. Good luck and have fun.