B&W 800 MATRIX

The 800s are 93 db efficient and drop only to 3 ohms minimum. They’re made partner with big iron, but I’m getting amazing results from driving them with a 38 watt push-pull tube amp. Point is, you can succeed with a very wide range of amps here.

Hi Mike
was thinking about this so I made some quick notes with my morning coffee. What to look for - bring flashlight. I realize this will be really hard but leave emotions at home.

Before you actually listen to them.
Note general condition of the wood veneer. Any marks/scratches. The sharp edges can be bumped when moving. Look for damage. Serial numbers match.
Make sure speaker grills are in good shape no tears and not missing any plugs.
Move woofers in and out by hand. Ensure they all move freely all the way in and out. No scratchiness is heard. If you hear or feel any rubbing the woofer's voice coil has been damaged mostly likely from a clipping amp. The voice coils are not very efficient and generate heat quickly. Their protective film may have melted or be deformed. This would not prevent buying them, but the costs need to be factored in. Pulling each woofer and having a pro speaker repair shop, replace the spider and voice coil will cost about $250 for each woofer. But everything is open, accessible and easily fixed. Just so you know.
Here is a pic of a good and burned voice coil.

http://circuitcellar.com/wp-content/uploads/2012/02/Klasco-Good-vs-Burned-Coil.jpg

fun video

https://www.youtube.com/watch?v=31768KUK9K8

Make sure the tweeters cones are not dented. Note the condition of the bolts for all drivers. Have they been removed before.  
On the back ensure serial numbers match. Look very carefully at the plates joining the sections. Are all hex bolts the same and are they all tight. Not stripped. Any missing?
Look at the WBT speaker wire connectors. Do they all tighten and loosen feely.
As far as pricing goes due to the speakers rarity, it usually comes down to the owner needs them moved as he is moving out of there, or there is a situation. Very much like if somebody needs a piano sold and gone. When you go there you will get a better feel for this.
Any price negotiating would based on Condition of the above items plus.  
They lose points if the 6 wood crates are missing. $500 value to me.
They lose points if the feet are missing. This also means the owner was listening without the speakers properly grounded. The bass was not as focused. There are many good replacement feet out there.
These are good.

http://www.starsoundaudio.com/OLDSITE/audiopoints.html

Note the pricing for the feet - use to negotiate as the speakers are missing their feet.

The speaker drivers - 4  crossovers each (2 midrange combined) are all separate and isolated physically. This means you can run 4 direct wires from your amp/s to each one.  This also means when testing them out you can play just that tweeter, both midranges and/or woofers separately. If the factory jumper cables are missing even though I would not use them myself, you could negotiate some more.

Mint condition to me means all the above checks out.

If I was selling these and there was someone interested that could come and pick them up and me not have to pack them up. This would be worth quite a bit to me and I would come down some in price. Time is money, and my back means a lot to me too.    If you like email me any pics you may have from the original ebay ad.

Hi cymbop - are you still babysitting those 800m's ?  :^)

Hello I also have the B@W Matrix 800 speakers. I drive them with a Mark Levinson 335 amp and use Transparent cables for the feed into them. Use the original jumpers with the exception of the mid to the tweeter i use a Transparent jumper. They sound great feel the room with great sound.
Enjoy Pete  

Yeah, Ct!  Still enjoying them on a nightly basis, and feeling thankful every time!