I have been demo'd the 804 D4 Diamond Speakers in a system where a selection of Digital Sources were used with Devialet 1000 Amp's.
The Amp's are able to be configured in many different ways, very user tweakable.
It was noted these Speakers can Bloom with certain Amp' settings, and the owners settings were tweaked by the attendees to create a much more honest coherence across the frequency ranges.
The Speakers come into their own following attendees chosen settings, and were substantially impressive with a Valve Based Circuitry for a DAC used on the Digital Source.
Hence, my earlier suggestion to investigate a alternate Source.
I am impressed by 804 D4 Diamond Speakers as a result of the demo's had using different Digital Sources. I have even made it known, I would be happy to have these used for a Demo' in my own system, and not many Audio Devices experienced get put onto that list.
I would not be hasty to consider suggestions to change Speakers.
My experience does leave me to strongly suggest Careful Valve Amp' matching would be advised if a Amp' of this Circuit Type were to be introduced.
The following is an attendees emailed comments following the HiFi Groups Meet Up at a Group Members Home to be demo'd their System:
" I can now see why the B&W's have such a reputation. Lovely clarity in the mid and treble and fantastic articulation in the bass. That they also look like modern sculptures is the icing on the cake.
Like John, my personal preference was that the speakers sounded better with the flat eq. I would even try pointing them straight down the room as from memory I think they have a lift in the treble and so may sound flatter when you listen slightly off axis. Having said that I am quite sensitive to treble so that might just be me ".