MHDT Orchid TUBE ROLLING


Interested in hearing about tube rolling experiences with the Orchid and other MHDT dacs, namely, the specific comparative sonic characteristics of the various 396a, 5670 and other compatible tubes used in the output buffer. My only experience is with the WE396a that Linear Tube Audio installed in my new Orchid.
pmboyd
How did you get the WE396a with your DAC? I just purchased one and it only came with what looks to be a GE tube. I'm hoping to try the WE396a out soon.
Waterclocker, I bought my Orchid from Linear Tube Audio. They supply and install a WE396a at no extra cost.
Unfortunately I missed out on that deal.  They were low on them and I had to buy it separately.  I got one of the last couple.  Certainly worth the cost of admission!  Seems a bit richer sounding and less digital.
I am the person who introduced the idea of using 6922/ecc88 family tubes in mhdt DACs, in the head-fi forum. As stated you need an adapter. I took a flyer on the idea after experimenting with every 5670 compatible variant tube. There were certainly great and meaningful differences among them but I evaluated the trade-offs between them as too constricting. Happening upon an adapter lit the bulb.

It's surprising that it works so well, because in the mhdt DACs, that output buffer position has the 6922 operating with a B+ around or slightly under 25v. Very unusual. But sometimes that works and in this case you give up nothing to get plenty. Going back to Havana Balanced ten years ago, through Atlantis, Pagoda and Pagoda Balanced, my preferred 5670-compatible tubes were Bendix 1964 production 6385, and Bendix or Hytron 2c51. The Tesla NOS equivalent was in the same realm. They pushed these DACs to be meaty, vivid and natural. But something was given up, a little, in elasticity and nuance.

The ecc88/6922 delivers everything good about the best 5670 compatible tubes, gives up nothing, then adds more. You'll hear big gains in soundstage dimensioning. Music is dynamically unleashed, spatially liberated and tonally more authentic still than what you expect from mhdt. Bass is deeper where appropriate, more fully realized and textured. In voice you hear more of the whole human pipe, less restriction to the throat. The whole presentation is harmonically more complete, vivid yet relaxed, natural. I use CCa and CV2492 tubes. Siemens and Valvo NOS 6922 work well too.

Phil
213cobra... Interesting post. I own the new MHDT Orchid and am currently using a Western Electric 396a. Do you know if a 5670/396a to 6922/6DJ8 tube socket adapter requires any circuit alterations in the Orchid? Petrhaps a question for MHDT.