Hey I'm only going by what Lampizator told me when I first purchased the GA TRP 2.
So, we can definitely use 6J5 in the TRP 2? If so, that's great. I have one or two (crates...) of those tubes.
Two of my custom headphone amps take those tubes natively with 6J5 sockets. My Supratek Grange...
Marconi Italy black plate 6SN7 is one of my favorite 6SN7. Also Marconi Italy black plate 12AX7. Very, very few European 12AX7 have the black plate. The only other two I know of are the very first British Mullard - just released for one year and the first Brimar 12AX7.
I have a lot of Italian...
It depends if I'm listening with speakers or headphones. If I want something warmer I'll go with Philips EL50/4654, 4689 or EL3N. Something brighter I'll go with Telefunken EL11. Something more as an "all rounder" GEC KT66 or early Philips EL34. Other tubes I really like with this DAC are GEC...
Don't suppose anyone on here knows the DSD sample format the TRP uses? Roon has died on me (and for a number of other users) and I've gone back to JRiver. I needed to configure my media server as a JRiver DLNA server and also needed to turn on DLNA on my SoTM SMS-200 where I have the TRP...
Philips EL51 from the 1950's if anyone is interested. They don't turn up too often. Used tubes, but should be good. I've purchased from this seller before.
https://www.ebay.com/itm/384328442409
Don’t think I’ve seen these tubes posted on here yet. GEC TT21. This particular version are from 1972 with side and top getter. KT88 with top cap. Some people are known to prefer these over the KT88, but I can’t tell a difference between the GEC versions.
Can also be made pretty simple by running a USB cable directly from a computer to the TRP. Obviously YMMV on whether this route is "good enough", but many people think it is.
And then there are plenty of great options (like above) from us hobbyists who like to complicate our lives - but often...
I don't think Mullard made a metal base GZ34 - just Philips. You might see Mullard, Amperex lettering, but the codes on the metal base of the tube give away the factory where they were made.
There were 4 different metal base Philips. You might drive yourself crazy 1) trying to find them all and...
WWII or late 40's for me with RCA. Later than that and they get a little too warm for me in my system, but I know others who really like the 1950's RCA tubes.
Looks like you have a different TRP chassis to me, because the adapter on the right works fine in mine.
Also, double check with the seller of the 4654 adapter. They will know as they also make EL51 adapter.