I ordered two 200uF 100V capacitors from amazon.com for $2.40 ea, which according to their specs are good for up to 200 watts. I wanted 200uF to get as close to the 200hz cutoff as possible. What I did notice was that the capacitors from Radio Shack were 35V which makes me wonder if they are only rated to 70 watts...much less than the amplified wattage. I don't know enough about this obviously, but the capacitors that I ordered seem to be much more in line with the equipment. But I could be all wrong again...just throwing it out for discussion.