By going to a larger four channel amp and bridging two channels for your bass and running the other two stereo it would keep things simpler - but if you are like me and pretty much run it wide-open all the time it may not give you that much more volume: a simple rule of thumb with amplification is, if all other parameters remain the same and you just double the available power then you will net an increase of 3 decibels. 3db is just over the minimum threshold that human hearing can hear a difference - you see where I'm going ? Now if you keep the stock amp on the top end and run a separate big mono amp on the bottom then two things will be influenced ... The top-end will be able to run much cleaner because the common power supply will no longer have to perform double duty of running all the output devices - just the ones running high frequency. The new monobloc has it's own power supply that won't effect the signal reaching the mids and tweeters - so you can run the bottom end really hard (distorted) before you will even hear it. If I can I always try to split up the power supplies feeding the top and bottom for these reasons.