VSA VR-4: problem with midrange drivers

If I use a lower powered amp on the top end ( I have a 100 wpc Aragon not currently in use) would that make any sense? I will also have the B&K checked out to see if there are any issues with it, but I'm concerned that sending 200 watts to the upper and 200 to the lower speaker modules is why I'm having the issue.

If the problem is amplifier clipping, using a lower powered amp (for either the lows or the highs) will make matters worse, not better.

Also, you are not "sending 200 watts to the upper and 200 to the lower." The power you are sending to each is determined by the music, the volume control setting, and the speaker efficiency, as long as the amplifiers' maximum power capability is not exceeded. And keep in mind that music almost invariably has most of its energy concentrated in the lower part of the spectrum.

Keep in mind also that if you biamp with two different model amps, especially ones with different power ratings, if their gains are not the same you would be introducing a volume imbalance between the lows and highs in horizontal biamp configuration, or between channels in vertical biamp configuration (vertical biamping with different amps of course not making sense for other reasons as well).

I second BDGregory's suggestions about how to go about addressing the problem itself.

Regards,
-- Al

My concern was that perhaps the drivers in the top module weren't capable of handling that much power alone.

To clarify my previous comments a little further, the mid/hi speaker drivers will see exactly the same amount of power when bi-amped as when the speakers are single-amped, assuming identical volume levels.

The voltage at the output of the amp channel driving the mid/hi section will be the same as at the output of the amp channel driving the low frequency section (at least in the case of a typical solid state amp having low output impedance), and will also be the same as for a single-amp configuration.

The current flowing into the mid/hi section as a result of that voltage will be limited by the speaker's crossover so as to correspond only to the mid/hi frequency content of the music, just as would occur in single-amp configuration. Therefore the power delivered by the amp to the mid/hi section, being proportional to voltage x current, will not change as a result of bi-amping.

The bi-amp configuration will, of course, make life somewhat easier for the amps, by reducing the amount of current and power that must be supplied by each amp channel (since each channel will only be powering one section of a speaker rather than both).

Re your last post, yes for vertical bi-amping the left channel output of the preamp should go to both channels of the left power amp, and the right channel output of the preamp should go to both channels of the right power amp.

Regards,
-- Al