MHDT Orchid TUBE ROLLING

I have both adapters and prefer the 6sn7 gray glass RCA vt-231, nice bass and natural airy detail. The clear glass and black glass are nice but always go back to gray glass. I thought I would like the ken rad vt-231 with big bass but didn’t work for me. I did like the 6922 bugle boy the most out of all the amprex tubes SQ,PQ and others. But always go back to gray glass rca.

Update.  The military jw2c51 arrived and it is identical to my civilian version in every way.  Both military and civilian versions say jw2c51 at the top of the tube.  Only the civilian version says we396a at the bottom.  Same ink, style and logo.  Same black plate, “D” getter and construction.

with 6dj8 and 6sn7 adapters for the mhdt units, one has a very very broad range of tube choices to roll, and both tube types have long illustrious histories and were made in various parts of the world to boot

you will get somewhat lower gain from some variants(esp. older 6sn7s), but since the tube is used as an output buffer only, that will not impact the dac's output voltage too much

for all tube rollers of orchids, stockholms, istanbuls and the like, just be careful -- be very gentle and use a steady and firm hand when removing the tube from the adapter, find the right orientation where gentle rocking pressure will loosen and release the tube pins, and especially when releasing the adapter from the socket on the dac's pcb board... the board is somewhat flexy and there are examples of folks breaking connections between the tube socket and the board below - jian at mhdt has been cool about sending replacement boards in the past, but one cannot count on his goodwill being extended indefinitely

My Orchid should arrive in the next week or so... I've purchased the Bendix 2C51, which has arrived. I see 2C51 printed on the side. Is there any reason to believe this will perform differently than those marked with 6385, and can anyone comment on the qualities of the Bendix 2C51 in the Orchid? Any reason I shouldn't rest here for a while?

Just wanted to say thanks for the helpful info. I left the stock tube powered on for a few days, but I never really warmed up to it. I’m not sure exactly what was missing, maybe just a bit thin. But a handy (and well made) adapter with an NOS Amperex 6DJ8 fixed whatever it was. Together it still cost less than the tube upgrade LTA was offering. (And it looks like they raised their base prices right after I ordered.)

My other DAC is a Chord Qutest and I expected with 2 very different approaches, I would have a clear favorite. So far that just isn’t the case. I might need to devote several hundred hours of careful listening to fully investigate. Sure would be handy if someone else could just figure out my preferences for me so I can just listen to music instead.