Using a Pre-Out to Bi-amp

The input sensitive is the amount of current required for the amp to reach full output. For example one amp might require one volt , another two volts. This is the governing factor in the choice of amps in this case I would think. Input sensitivity is always specified for a power amp , I am less familiar with voltage gain. I would assume that it is the mirror image of sensitivity, describing how much the initial preamp signal is amplified. But it is not necessarily the case that you should have equal output from both amps. The tweeter or tweeter/midrange will require much less power than the woofer so having the same output from both amps might overdrive the high end. In the past when amplifiers were offered with several amps on the same chassis the treble amps were always of considerably lower wattage than the bass amp .I think we are saying the same thing with different terminology. The critical factor is the bass amp having greater sensitivity
( higher voltage gain) so that it can be adjusted by a volume control as we have both suggested.

I totally disagree with most of the posts-it can't work. Forget getting the same amp gain. There will definitely be a delay caused by using 1 internal amp and 1 external. There is no way they are getting the identical signal at the identical time. I'm a firm believer that you shouldn't bi amp unless you use 2 identical amps.

Thank you for all your responses. Within the next day or so I am going to hook up both amps and try it. I will get back to you about my success and / or sonic failure.

Jim