Hi Blackmore,
Sorry I haven't posted updates in a while, I've been busy burning in my newly acquired Mullard tube and Berkeley DAC. I've got about 70 hours on the tubes so far, and I feel like they're fully baked in now (I think most of the change occurred about 40-50 hrs in).
The verdict is in, and it is good. I'm going to try not to start off by injecting too much hyperbole about this tube so I'll use one word to describe their sound signature: "natural".
Put your hyperbole filters on now, you've been warned.
The most striking characteristic about the presentation of these tubes is not necessarily in their commission, but in their omission. There isn't a hint of saccharin or other artificial sweeteners or flavors; this is sweet juice straight from the sugar cane; light, satisfying, and delicious (with abundant texture and chewiness thrown in for good measure). It's like being raised on soylent green your entire life and finally being given fresh fruit. It's eye opening to say the least. After the burn in, everything's become more lucid, the mids I commented about seemed to recede into the 3D presentation; overall just a smoother, more natural, refined tonal balance.
To contrast, my TJ Mesh globe is a good performer with a clear intent to voice towards the midrange of the spectrum (this is probably it's strongest attribute), however there's a definite lack of bass quantity, and treble is probably rolled off a bit too much (although a lesser sin then being "hot" IMO). Overall there is a bit of artificiality to it; you know you're being catered to to a certain extent, and something about the entire presentation doesn't sound quite real. As you'd expect, the Taka decisively trumps it in every area conceivable, rendering a checklist comparison futile. The whole is indeed greater than the sum of its parts.
If this is what the modern masters are up to, we're in for good times. There really is something to be said for old world craftsmanship; a handcrafted product may not look perfect, but in this case, the sonic results are self evident (Man-1, Machine-0). My minds ear imagined and craved a sound lauded on about by those that have been privileged enough to experience an etched based WE300B from the 50s. At $4K+ USD a pair, I doubt that common sense will get out of the way long enough for me to get the opportunity to; the funny thing is I long for it a LOT less now.
If you're seeking a more "organic" sonic experience out of this tube architecture, you'd be hard pressed to do better than this.
I have been lucky enough to have 3 pairs of differ 300B's, but also lucky enough by trying some Chinese made, which made my feelings about them very clear, never again.