After discussing replacing the cap that comes with the Avatar cab with many here including Bill Fitzmaurice I decided to venture out and build my own. I used a crossover calculator Bill sent me via email. Previously I tried a 3K (12db)then a 3.5K (12db) crossover prebuilt. The 3K allowed the horn to distort due to the low end. The 3.5K was better but still a little honky and very slight distortion due to lows. I decided to go for 4K. I put the values in the calculator and and came up with a 3rd order Butterworth (18db). This smoothed the sound out. I used KimberKap audio capacitors from Parts Express. They are a bit pricy but not as much as some of the Pro Audio caps. This made the biggest difference in audio quality. I freely passed all the harmonics and tones of the bass strings that I had not heard till now. The components used are: C1= 3.2mf @ 200 volts C2= 10mf @ 200 volts L1= .24mh at 800 watts I used an epoxy glass circuit board from Mouser Electronics and wire ties to hold the components to the board. I cannot stress enough what a good capacitor can do for you. When I compared it to the Dayton board with cheaper polyprophyline caps the Dayton sounded dull by comparison. The KimberKaps are soleful, clean, quiet with lots of clarity.