Passive biamping question

True, but 3db is still the difference between 150 and 300w, 200 and 400, etc. Say, you have an amp that you really like but want new speakers that are less efficient, rather than sell the amp, you could buy another amp exactly the same, new or used, and it could be very cost effective.

Assuming the amp is not bridgeable of course.

All true but, if you consider the audible effect of a 3dB increase, it is nearly inconsequential.

Maybe this info can help you make a decision. Currently, I'm doing a vertical biamp in my own system. I'm very happy with the results. To be honest, I've never heard of any negative downsides to doing it this way. But after reading Kr4's post, I think that some caution may be necessary. It's entirely possible that it may not work the same for everyone. The main idea behind a vert biamp it to use work both amps the same amount (basically what I said in my first post.). I don't see how you can have any negative effects doing this way, but that doesn't make me right.

Based on that, I would find a way to demo a vert biamp system with the components you are going to buy. Also, the components in my system are known to sound very good when configured this way. (2 Ayre v5's powering Vandersteen 2's.)