MB QUART VS05BE bookshelf speakers - My take and Impressions

[KEW]

Anyone know for sure what the specified impedance on the vs05's are? I'm getting a new receiver that needs to be set differently for 6ohm loads.

Poke around the internet some more.
Every time I have read a review of an amp with this feature that included real test measurements, they said do not use the lower impedance setting no matter your speakers.
Here is an example:

NEVER USE THIS SETTING!

With the impedance switch set low aka the 4 ohm setting, the MX-A5000 only delivered 63 watts at .1% THD +N with 5 channels driven. We ALWAYS recommend leaving the impedance switch set in the default high (8 ohms or more) mode regardless of the speaker load you will be using.

Above from about half way down just before colorful bar chart:
http://www.audioholics.com/av-preamp-processor-reviews/yamaha-aventage-cx-a5000-mx/processor-and-amp-measurements


another discussion:
http://forums.audioholics.com/forums/threads/yamaha-6ohm-setting-safer.53227/

As best I understand it the lower ohm setting essentially protects your amp at the cost of SQ, by limiting power output to prevent overheating (more current running through amp since less resistance at lower impedance). This might reduce the number of complaints the manufacturer gets from customers, but you are throttling the high-current capability you paid for! Better to test it by working it as hard as you ever expect to and keep an eye on the temp of the amp!

Note: This is just my understanding from reading reviews. I am absolutely no expert on this.