VSA VR-4: problem with midrange drivers

I would start by using another amp entirely. Have you tried them in NON-biamped config? That's where I would start before replacing speaker drivers, or sending amps in for service. Also, if you have identical amps I would vertically biamp them, though this shouldn't effect the issue you have.

I have VR4 gen III's and they don't require 200 watts to sound good (indeed they sound wonderful with a 35 watt tube amp (non-biamped), and I normally drive them with a 140 watt ss amps in vertical biamp config. So testing them with your lower power amp shouldn't be an issue at all. Also, unless there's a significant sensitivity difference with your top and bottom amp, driving the mid/hi module with the EX442 shouldn't be an issue either.

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

Thanks guys. I understand that I am not sending the 200 watts to either module per se, that it is dependent on the source recording, and where I have my volume set...my concern was that perhaps the drivers in the top module weren't capable of handling that much power alone.
I thought about running the speakers with just one amp...I have a good set of jumper cables that were part of my purchase, but the VSA manual does suggest that they will sound better bi-wired or bi-amped.
Also, I am not clear as to how to vertically bi-amp. My speaker cables are not identical, I'm using MIT on the bottom end and Synergistic on the top.

VSA manual does suggest that they will sound better bi-wired or bi-amped.
Also, I am not clear as to how to vertically bi-amp. My speaker cables are not identical, I'm using MIT on the bottom end and Synergistic on the top.

I called VSA when I bought my VR4s - Albert answered the phone personally on the second ring! I asked him about biamping or using a single high powered amp (I was considering having my Eagle 4's converted to Eagle 11 mono blocks. He said they're best when biamped. I've since tried them with several different amps and none best Eagle 4s in vertical biamp config.

Vertical biamping is easy - but you need identical amps. One stereo amp goes to one speaker, the second to the other. Connect one channel of each amp to the mid/hi, one channel to the bass. You can use different cables for mid/high if you like. There is a biamping thread in the archives where Steve McCormack describes at length why vertical biamping preferred when you're passively biamping. It's worth a read Here.. he also discusses using different cables . . .