Hi,
I have had some time to listen to the 803B/291's
I find one horn goes decidedly lower in frequency than the other. Have not measured it but it is clearly audible. I am crossing these at 350hz 24db/oct. This means the output is -6db at 350hz.
I noticed when inspecting the diaphragms, that they are original Symbiotik. one had some very slight marks on it not really deep impressions. I cannot say if that is the one that is misbehaving or not. I did not mark it.
I do plan to replace these with GPA 390's since they are guaranteed to 300hz.

Any speculation why one driver would not go as low as the other?

Kevin
Nov 23 2010