I had similar problem with my Bernabe and I settled with Ramirez strings, check out this thread
Bernabes are very sensitive guitars and they do tend to produce a little metallic sound, it's the way they are and I actually like it. But there are a few things you can do to make it a bit mellower so it would sound more "ethereal" rather than "metallic". Strings is one of them. The other is saddle, I replaced mine with TUSK and it made the sound a bit softer and more pleasant, while the bone saddle would make the sound too zingy and clacky. And the last but not least is the plucking technique. Bernabes are very unforgiving and sensitive to the RH plucking style, you need to develop a good plucking technique to produce a nice sound. Make sure you pluck deep with a lot of finger flesh and then release by nails, but the nails need to be very round and glassy polished. Bernabes will grossly amplify any nail roughness and unevenness due to their extreme sensitivity. Also, try plucking at different angles of the fingers with respect to the strings, less angle produces mellower sound until it becomes dull so you need to find a compromise. But as with any guitar one needs to adjust the technique to get the best out of each instrument.