MHDT Orchid TUBE ROLLING

I too want to bump this thread and thank 213cobra for this suggestion; and to encourage anyone who is looking to roll tubes in their MHDT to consider using the 5670 to 6922 adapter.

I installed the adapter in my Istanbul and rolled in a 1970 Siemens E88CC. Stunning results. Absolutely an improvement over every 5670 I tried. If you’re considering trying this, don’t hesitate! It’s worth it.

I’m using this in my Grannyring modified Orchid. Much clearer? More airy? Than the NOS Mullard mentions in this thread. In my system, my ears of course.
E188CC / 7308 Siemens, West Germany made, 1960s wide getter support post, gold pins.

I have a MHDT Pagoda and rolled a Bugle Boy 6DJ8 into it this afternoon.  I was waiting for the adaptor for a few weeks.  I'm thrilled with the result.  Its soundstage is massive and dare I say that the PRAT is a plenty.

I want to second the previous post. I too went through the WE 396 tubes with my Pagoda DAC and while the 396 tubes  made the pagoda DAC sound better than my previous three DACS it really wasnt a huge change in sound presentation. In fact I started believing that good DACs are pretty similar.... just a matter of taste. (wrong)  SO not having any mind of my own,  I started experimenting with a 396 tube converter and sticking in all the old 6922/7308/E188CC tubes that I had collected during the last 10 years. 
I tried a Valvo tube, it was ok...not much better than the 396 tubes BUT still better. I rumaged around in my "tube box" and spied a  very cool 6n23p russian tube and said WTF lets throw that tube into the Pagoda and hear what happens? WHOOO that was a very significant improvement....I really liked that tube's sound for a few days, actually still do... it was very transparent!!!!  Then I thought hell this is COVID I cant go anywhere,  I might as well have some fun take some money from my daughters college fund (shes not going to classes now) and do some MORE BIG TIME tube rolling. And then having nothing to do I went on Audio Gon and spied the previous post. Having no impulse restraint, I Immediately called Brent Jesse and said, hey send me your best yube for the MHDT Pagoda. Brent said ok ....its pricey... BUT its on the way....yesterday I received it and put the 7308 MAZDA tube in my DAC. I am really excited right now that a realative inexpensive "high fi" purchase could bring me so much music listening fun!  Sorry I know this is ong winded (too many cocktails while writing this missive).

Cocktails and audio? That's the way to quarantine.

Which tube gave a laid back midrange sound? I've tried the Pagoda and now the Orchid and the midrange is still a bit too in your face?

@traudio
Which tubes used in the Orchid were "too in your face"? Were they the stock tubes?

I just ordered the adaptor from garage1217.
Do you think this tube will be ok?

https://www.thevalvestore.com.au/home/77-6n23p-ev.html?search_query=Soviet+reflector&results=14

I just ordered the adaptor from garage1217.
Do you think this tube will be ok?

https://www.thevalvestore.com.au/home/77-6n23p-ev.html?search_query=Soviet+reflector&results=14

that russian tube will give a spotlit treble, a recessed midrange and decent bass in a mhdt dac, i personally think it hurts the sound in the midrange, where the dac should really shine

i would suggest an old stock european 6dj8 equivalent tube from tungsram/hungary or ei/yugo if you are trying to stay at a reasonable cost (otherwise go for mazda telefunken or dutch amperex ones which are $$), these will give a nice lively treble but the midrange will be much more textured and palpable

one other important note... the g1217 adapters have long pins... do NOT insert them ALL the way into the mhdt tube socket, or the adapter pins may damage the underlying socket solder joints ... ask me how i know  :(  -- instead, look at the pin length of the stock 5670 tube and insert the adapter socket only that far into the mhdt dac tube socket

Hi jjss49

How do you know how the Russian tube would sound? Is that from experience with one, or from someone else's review, or is there a "way to tell" ? 
I've just tried the Russian tube today (the adaptor just arrived today) and the supplier chucked in a 6dj8 from matsushita. Might try that also. 

If all else fails I'll remove the adaptor and go back to the  TESLA 6CC42 pinched waist, military edition i was using. 

Hi jjss49

How do you know how the Russian tube would sound? Is that from experience with one, or from someone else’s review, or is there a "way to tell" ?

i have it here, have listened to it - it is the only way to know, for sure

i have many pieces of gear that run 6dj8 equivalents... i have quite a collection of these tubes (~200 accumulated over the years), probably 15-20 different makes and variants... and have listened to most if not all of them all over time

Try a NOS Siemens, Telefunken or Valvo CCa. All-but-equal is the Mullard CV2492. The Tesla 6CC42 is very good in the native socket, as is the excellent Bendix 2C51, but these alternatives in the 6922 family via adapter are in all ways better.

Phil

I’ve been considering an Orchid, and I just noticed on the LTA website that the WE396A upgrade is unavailable, but they are offering an Ericsson 5670 for the same price. With all the hoopla about using 6922 or 6SN7 converters, I’m wondering if I’m better off skipping the small tubes altogether and going straight to bigger tubes. I see the 6SN7 requires a case mod and the tube sticks up quite a bit. Does the 6922 require a mod as well?

6922 on top of converter will go through the cut out of the top plate... unlike the 6sn7 whose diameter is larger than the hole in the top plate, thus running that tube w converyer you need to run without top plate or enlarge the hole

but the 6922 with converter plug will sit tall, will protrude up far above the level of the top plate by 2/3 of the glass envelope of the tube

I tried the 6SN7 with the converter in my Orchid and did not care for it. No experience with the 6922.

Tube Depot has the we396a 1958 “D” getter just in.  Or is it a Western Electric JW2C51?  I ordered one.  Let you know.
https://tubedepot.com/products/396a-2c51-we

Curiosity Question
                             I have a DAC and Phonostage using E88CC's.
How does the 6SN7 find a usage in a Circuit that can use the E88CC, 6922, 6n23p Valves.
I would be keen to learn about this as an alternate option for my own trials.   

pindac,
https://tubedepot.com/products/6sn7-to-6922-adapter

garage1217 makes far superior adapters than those chinese units 

I have some Russian 6922 equivalent tubes leftover from a tube output CD player I had years ago. I'll need to try to identify them before I try any, but I seem to remember them being 6N1P or 6H30. Anyone try one of those? I think think they are only loosely compatible (heater current?) and I'd rather not let the magic smoke out of any components.

Orchid ordered. Going to try the stock tube first (weird, right?) Probably get the 6922 adapter if I can positively identify the tubes I have floating around. Are there any 5670 or 6922 new production tubes worth a look? I have notoriously bad luck with NOS tubes.

Thank You for the Link.
This will be a good upcoming experience to be undertaken.

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. 

Sure would be handy if someone else could just figure out my preferences for me so I can just listen to music instead.

This is so true.  I love the hunt but at the same time get so frustrated.  I guess that's why dealers are great for most people.  Give them a budget, tell them what you like and they put a few systems together that they already know work. You then choose. No faffing about with tube adapters (I didn't even know they were a thing before I got my Balanced Pagoda) and 50 tube choices. BTW, I like the Amperex you have the best of the 3 I've tried.  I also have GE 5670W's and Tesla E88CC's.

+1 @zm108

Just (I mean I'm two albums in) installed the 5670 to 6922 adapter.  Great sound and I'm using a lot less expensive tube than the WE D getter.

What do people do with their old 5670 collection?

here is my tube rolling experience w/ MHDT Orchid. (before & after mods by Grannyring)

Before mod:-

I had some OS 6SN7s laying around & NOS Tung Sol & Sylvania 2C51

Sylvania 2C51 sounded better...but not something I wanted to live with.

I got adapter from Garage1217....

Of all the 6sn7s..Sylvania Jan CHS 6sn7WGT was the best ...a bit flat, but something I can live with and enjoy the music.

But wanted to see if I can get better sound out of Orchid.   After talking with 2 people, who offer mods for Orchid, I decided to use Grannyring.   He was willing to tweak his mod to suite my music listening preference (cannot have bright sound at all)

After receiving the mod:-

1) The order of preference for 6Sn7s changed.

Tung-Sol UCn-CTL-6sn7wgta sounded better (more relaxed) than SYlvania.

2) Also the Sylvania 2C51 sounded much better.

almost seemed like the mod was specific to make 2C51 sound better.

So I tired the following 2C51/5670 family tubes

I have had experiences of using Vintage E88CC and have been demonstrated some of the Valves mentioned above in devices that I own.

As a result I have acquired a selection of early 60's E88CC's from different producers

One Tube not mentioned and very worthy of being trialed is the early 60's Mullard CV 2493, these are rare to find, even thought not too long ago there was a Matched Pair for sale in the USA, for very fair money, if compared to present UK prices.

I also recently heard on two separate occasions an early 60's German produced E88CC in a CDP and the impact it had made on the device and within the HiFi system was extremely impressive .

The second listening was with a Group of attendees who had at an earlier date, been demonstrated the CDP with the stock valves. The response from the additional attendees were no different to my own, they were in awe of the presentation on offer, and very clear about the valuable impression being made in their appraisals. 

I just want to say thanks to jjss49 for helping me find the right mix of tubes for my Istanbul and Blue Circle pre. His assessment of the REFLECTOR 6H23P-EB / 6922 (PREMIUM) was spot on and switching back to Amperex made all the difference. Great to have some solid advice from someone who's listened to a number of the different options. Saved me a ton of angst and painful discovery.