Ran across this shootout that I thought the Outlaws would be interested in reading. Looks like the the Outlaw bookshelf won the first couple rounds before losing to Epos and the modified av123.xls. Here is the link
http://www.stereomojo.com/Small%20Speaker%20Shootout%202007/SmallSpeakerShootout2007Part1.htm

Unfortunately, the fact that they used tube amps clouds the testing a bit.

I'd say a better test is to use solid state amps that are known to not add coloration or distortion into the mix...both issues that tube amps are known to do.

By choosing tube amps, they made it hard to distinguish between whether an attribute is from the speaker itself or being imparted by the amps.

Basically this test tells us what speakers are good for tube amps that few will ever be able to replicate, but for the rest of us, the meaning is a bit more muddled.

Nice to see the Outlaw speaker fare pretty well against the competition though. Be interesting to see what their measurements show.

It was an interesting shoot-out, and there's some discussion of it going over at AV123 . Those Dodd tube amps have been getting a lot of talk lately (they were at RMAF last weekend). I did find myself wondering what settings might have been used on the Bookshelf (either the boundary compensation switch or the high frequency switch), but even without that information it appeared that the Bookshelf performed quite well.

Those amps are pretty darned impressive looking.

Kind of surprising that simply upgrading the crossover would make that much difference to a speaker.

Well, the upgrade to the X-LS was fairly large-scale. It uses a new tweeter that will eventually be in production but that I don't think is shipping yet (which by itself adds almost $100 to the price of an original X-LS), it includes a different crossover design in addition to using significantly more expensive components in the crossover network, and it includes adding dampening material to the inside of the enclosure. That's why the price for an already-modified "Ninja X-LS" is $1000 rather than the $300 that a stock X-LS will cost when the new tweeter arrives.

They published the measurements today.

http://www.stereomojo.com/Small%20Speake...easurements.htm

By the way, cost for each of the speakers was $1000 or less per pair. So ninja's mods added something like $200-$250 to the cost of the original speaker (can't remember if the new X-LS will be $250 or $300).

I wonder if the low impedance numbers they were seeing are indicative of the Outlaw BLS in general or points to an issue with the units they received.

Or is this actually fairly typical for loudspeakers? The reviewers made it out to not be the case.

If I remember correctly from my readings here and elsewhere, some amps might have issues with the dip in impedance.

It is quite normal for the impedance of a speaker to vary with frequency. Some go from a low of around 3-4 ohms to a high of 70 or so and are rated as nominal 8 ohm designs.
This variation with frequency is a result of various electrical (and mechanical) resonances in the crossover and drivers. It is possible to construct a speaker whose crossover network presents a constant impedance to the amplifier but it requires additional components and design time. (read $$)
Kef did this for the 107 series (early 1980's) but most manufacturers don't bother.
Apogee Scintilla speakers had an impedance curve that dropped below 1 ohm at certain frequencies. There were only a few amplifiers capable of properly driving them.
A well designed amplifier with low output impedance should have no problems with any of the speakers in the shootout.