JVR, I've just recently come across Berning as a possible OTL amp for my constant 4 ohm load KEF Ref Series 104/2 speakers. MY question to you is what ohm rating are your speakers and if they aren't 4ohms then what experience have you with the Berning driving a 4 ohm load?
Question #2 - does running your CD player through the Joule preamp sound better/worse than running it directly into the Berning?
I would like to recommend trying the Luminous Technology Synchestra Signature interconnect cables with this system. I know the Merlins love copper but the Berning really likes silver. Maybe this is the happy medium. I think you may be surprised at what type of improvement you should realize.
Of course don't buy it, you have to try it risk free first. I'm not gonna recommend anyone buy ANY cable without a listen. I would try between the BAM and the amp first. Next between the DAC and pre.