Martin Logan Balanced force 212 Subwoofer in a two sub configuration

Picked this sub up back in Jan this year. I am very impressed with it and it does an amazing job for both Movies and Music. With that said however this is not a review. This is more an FYI for those who may be interested in purchasing one (Martin Logan Balanced Force 212 or 210), or for those who own one and maybe have not yet run across this. My existing listening room is setup in a dual sub configuration with subs in opposing corners (front and rear) The Balanced Force 212 is in the front of the room with a Power Sound Audio V1500 in the rear. I decided to just see what things would sound like if I front loaded the room and placed the PSA sub in the front right corner with the ML BF in the front left corner. To keep from doing anything permanant I decided to daisy chain the subs for testing purposes instead of running the sub cable from the second sub out on my pre amp. It was just easier to run the cable between the two subs. Thinking most subs with an output would allow this. Once connected I noticed that the PSA sub would not wakeup when playing content. This usually is a pretty straight forward thing to do and there is no magic button or switch usually necessary to accomplish this task, well you get the idea. In troubleshooting the first thing I noticed was that the output jack on the rear of the ML was marked "multi" as opposed to "sub out"which is rather standard. So reading the manual regarding adding another sub inline with the BF the picture I was getting was that this particular output is not your typical passthrough LFE output. With  the ML BF 2x subs ML sells a Perfect bass kit that works like automatic room correction software such as Audyssey, etc, and the digital microphone that comes with each PBK is tied or linked directly to the SS#  of each sub. If you want to run the software on two different subs guess what...you have to buy two PBKs ($100 ea).  So back to the multi out on the rear of the sub.. turns out if you daisy chain two ML BF subs you only have to run the PBK on one sub (first sub in the chain) and the PBK data will be passed to the second sub by the multi output on the first sub (no need to spend the second $100). I called Martin logan to just make sure that I fully understood the manual and to make sure that there was not problem with this $4K sub. After speaking with a couple of very nice gentlemen in support they were under the impression that the multi output on the sub should be a simple passthrough however to be on the safe side they had someone from service call me back to discuss further. The service guy did called me back (very quickly) and after speaking with his engineering folks about this it turns out that its true the BF 210 or 212's multi output feature will only work with other BF (balanced force) subs. After thinking about this I decided to just give you guys a heads up that if you have one of these beasts and try to daisy chain with a sub from a different manufacture with the BF sub being first in the chain that its not going to work. It will only work with another ML BF sub so your sub is not broken. I am hoping  that Martin Logan updates their documentation to clearly state this because if you buy two the dealer may try to sell you two PBK kits and you will only need one so clear documentation  is in order. 

Turns out that I did not like the sound of the front loaded room after all and decided to put the PSA sub back in its original  position in the rear of the room. Really would not have been a deal breaker for me either way since my pre amp has two sub outputs.. However I think that the work around for this situation would be to daisy chain with the other manufactures sub as the first sub in the chain.. unless you  have a PSA sub like me that does not even have a sub out output on the sub. Otherwise split at the pre amp with a Y cable. 

-Keith