hi, thank you you have been very kind, now I see to finish the restoration of these 4430 ... this bass is not very good for now, there is a lot but it is not nice ...
In my opinion, bypassing the biamp switch is the single biggest upgrade (followed by Radian diaphragms in the horns). The biamp switch is a piece of crap that oxidizes badly and dramatically impairs the bass response. You should enjoy much better bass without it. See thread here:
Andrea, did you ever get your poor bass problem with your 4430’s sorted out? They should never have a problem with bass output.
The first thing I would look for is either the amp to speaker is wrong polarity to one channel, or one of the woofers is mid-wired so it it out of phase with the other channel.