Hilarious!
I don't really know what I want to know. It's just that there doesn't seem to be a rhyme or reason behind the model designations, or numbering systems. It's just mass confusion.
Like when I go to a site like Wilson Audio, I can pretty much find my way around and tell which model is the flagship, which is entry level, and where the others stand in relation. That is 180 degrees from what Usher offers.
It's interesting b/c I am someone who never ever th ...
The entry level speakers are the Usher series. They use very stoutly built MDF cabinets with wood veneering. These all range in price up to less than $1K.
The X-series is the next step up. The X-708, X-718, and X-719 are priced within $50 of each other, with the X-708 being least expensive and X-719 the most expensive. The X-929 is quite a bit more pricey and is an X-719 on steroids. The X-616 center channel is designed to work with all the X series models and the "6 Series"
The "Six Series" is the brainchild developed for the USA market. These are all Joe D'Apolito designs from the ground up. They mate with the X-616 center channel for surround sound applications and there will be an on-wall dipole surround speaker and matching subwoofer coming soon. Look for it in the coming months.... models in this line-up consist of the CP-6311 ($2100), CP-6371 ($2900), CP-6381($3400), and the new CP-6391 which was shown in final prototype stage at CES (~$4400 but not certain yet).
The Compass series consists of a number of models that are geared for two channel music listening only. These models existed before the "6 Series was created. The owner of Usher Audio is a die hard two channel guy and trying to get multi channel packages developed has been a struggle to say the least

The Dancer series is the flagship series for Usher for two channel listening. They utilize very very expensive curved cabinetry that is absolutely gorgeous to see in person. These models include the CP-777, CP-8571, CP-8871, and CP-8872. This change to beryillium tweeters and new midrange drivers is the first change in ~5 years for this speaker. Also included in this series is the AC-10 and AC-20, which are being changed to include the beryllium tweeter AND new beryllium midrange driver.
The most expensive model Usher makes is without question the D-2 horn speaker. It is a MASSIVE speaker and is one heck of a unit for a very fair price compared to the competition. It stickers at $19,999.99.
Admittedly Usher does have a tremendous amount of offerings at all price points. They don't just cater to one particular market segment or price point. I actually find that appealing. If someone is strictly doing two channel audio, there are a great number of choices. Multi channel audio is handled in the low end with several levels of the Usher series and the mid price range with the "6 Series". High end two channel audio is handled with the Dancer series and D-2 horns. I don't find Usher changes models any more or less than a lot of other manufacturers. In fact, they have been pretty consistent with their models, and have been working to improve the existing designs while keeping prices the same.... or they have introduced a new model here or there at the behest of customers and dealers looking for a particular package (i.e. why I have been hounding them for months for an on wall surround speaker and matching subwoofer).....