@rauliruegas wrote: "In my case was a : " win to win ".
That's GREAT!
Using a very-high-quality cap in series with the amp's input as a high-pass filter is probably the most transparent highpass filter format.
The theoretically possible downside is, in the octave above the calculated -3 dB point the output is diminished by an average of about 2 dB, and by almost 1 dB average in the octave above that. Also the best blend in the crossover region with the steeply-filtered subs might be where the mains are minus more than 3 dB, which increases the region where you are losing energy due to the broad nature of that first-order highpass. THIS IS NOT NECESSARILY BAD! It might be an improvement, and it might not; room effects will play a major role in this region so it's impossible to predict accurately.
Duke

