MHDT Orchid or Lampizator Amber 3?

Thanks to Grannyring's "ace skills" and "superlative service" Orchid Dac will be in my system tomorrow afternoon and his Amber 3 tomorrow evening.

Tuesday morning at 8:30am Grannyring paid for USPS Priority Express "overnight" to ship my Orchid Dac to Ohio, guess what, it just "arrived" in Nashville, TN.   Wednesday evening at 5:30pm.

I called the sorting hub and got an attitude with the bums rush, I asked her to please slow down so I could give the tracking number, finally.

She said "oh, the guy didn’t pick-up all the express deliveries, it’s in the back here"

They’re not the only ones, UPS and FedEx can F$$K up a cup of coffee too, nice work.

I know I’m not alone, just the principle, when you pay extra, it seems to get worse.

My experience is a good preamp sorts out complex passages, I run a CEC transport and TRL 6SN7, works for me.

FWIW, I owned and sold that Yggy dac, the slightly modded Orchid sounds way less bright and digital to my ears and in my system.

Since the Amber 3 has come into mention by grannyring (who modded my Orchid)
Bill and myself would say it’s pretty darn unanimous the Amber 3 along with Orchid sound way more musical and natural to our ears.

Thanks from Mark above, things are very interesting: https://www.head-fi.org/threads/mhdt-labs-r-2r-nos-tube-dacs.798259/

Thanks to Mark again,
http://www.garage1217.com/garage1217_diy_tube_headphone_amplifiers_012.htm

I ordered two: https://www.ebay.com/itm/NEW-5670-2C51-396A-6N3P-TO-6922-6DJ8-PINOUT-TUBE-SOCKET-ADAPTER/25448328039...

Thanks stewg,
Grannyring and I were a little concerned about that procedure.
I have four extra NOS 1964 Siemen Halske E88CC gold pins for my Cal Audio Aria.
Looking through my storage, I found six NOS Marconi 6SN7s, there’s also an adapter for those, but that’s another story down the road.

What's a "professional" review?

Musicman, 2nd one from bottom, specific to convert to 5670 / 396A socket.

50'-60's Marconi's

Do they support 6SN7 tubes with the proper adapter (Garage1217)?

In all our dacs, tube is acting as a buffer.
So, the tube is a passive compnents in circuit and so a fixed set up (bias). No needs to adjust resistors’ value for most tube.

However, the tube is working on -17.5 to + 17.5 volts, quite a very low voltage in tube’s world.
5670 can works on this low voltage because 5670 was design and developed for minitary communication equipment during WWII. So, it can be work on hardest enviorment such as low battery source and hard vibration. All pencil tubes were designed to be used in air plane, they also have same characteristics like 5670. 6SN7 is a commercial tube, it may also works on our dac but sound must be another issue.

Best Regards,
Jiun
Mhdt Lab

Subjective/anecdotal impressions would suggest that 6SN7 tubes do indeed work.

2nd from bottom:
http://www.garage1217.com/garage1217_diy_tube_headphone_amplifiers_012.htm

Same place on eBay: https://www.ebay.com/itm/GARAGE1217-6SN7-TO-5670-396A-TUBE-SOCKET-ADAPTER-OUTSTANDING-BUILD-QUALITY/...

I have both CV-181Z and 6SN7, but I will run *6SN7* FIRST, to be sure things are smooth and steady.

Hole needs to be enlarged like I mentioned (7 posts above) for 6SN7 or run topless till you decide.
The hole would need to be larger yet for CV-181 obviously, if I do that, I’m machining it properly.

The E88CC, 6922, 6DJ8 family will poke through the stock size hole about a half inch or so above plate.

CV-181Z vs. 6SN7: https://www.tnt-audio.com/accessories/shuguang_treasures_cv181_e.html

I came up dry too, one thing I found was this image search: 
https://www.google.com/search?q=abbas+audio+dac&source=lnms&tbm=isch&sa=X&ved=2ahUKE...

Decent machine shop could do it, only needs it if using 6SN7 or CV-181.

Singles or pairs "Z" series little warmer: https://www.ebay.com/sch/i.html?_from=R40&_trksid=m570.l1313&_nkw=CV-181-Z&_sacat=0&...