Amperex 7308 vs Siemens 6922 sound differences

Keep in mind that it all depends on the vintage of the Amperexes or Siemens involved. I tried both white label USA Amperex 7308, and West German Siemens 6922. I would say that there is a significant difference in sound quality, but not one that I would call better. I personally have never been as much of a fan of the Amperexes as some are. I find the Siemens to have a similar overall tonal color (that's not a negative), but a little leaner, with a little finer delineation of high frequencies, and maybe a little faster sounding. The Amperex gave me a more robust sound. Images a little more fleshed out with very stable imaging. But overall, they made the Tjoeb sound a little less modern and a little reminescent of vintage tube equipment; not necessarily a bad thing. Both are very good tubes, and much better than the stock Phillips. My very favorite by a long shot has been the German Telefunken 6dj8. Beautiful, wide open sound, with great tonality, and soundstaging. If you ever look to buy a pair make sure that they are real Tele's with the <> on the bottom. Sometimes they are rebranded Siemens.

Keep us posted.

I am uncertain and think that Amperex was not a maker of a tube they boasted as a 7308 I do know of some of their 6922s. Amperex was a Phillips product and while originally based in Heerlen Holland Phillips the parent company bought out a number of other manufacturers including Mullard.
You can buy an Amperex from Hicksville long Island USof A a British Amperex . German Amperex one or one made in Holland. The 7308 is a premium select member of the 6922 production. In any event the variety of Amperex tubes around due to age and origin make it impossible to be at all certain what tube you really have.
The nation of origin was applied by Phillips at their discretion without regard for the actual nsource. On top of all this Amperex has to be one the most copied, knock off tubes, found on the market.
Whilst only a small time tube collector, I just don't recall a 7308 from Amperex, my gut says something is not right here.
The Siemens West German tubes came in a couple of flavors as well but the vast majority are Simply Siemens/Halske Rohrer (tube) and are very good tubes in terms of linearity, they keep their cool and rarely if ever get loose. I also find them well balanced thruout the spectrum they are really consistent. Some just don't want a tube this clean sounding and is a bit cool.
I found that despite it's seemingly gratuitous role in a CD player the tube you choose has a very audible impact. I ended up with a Amperex USA as my favorite for this application but liked the relatively recent vintange Siemens 6922 almost as much but more sterile and also would roll a Mullard CV2943 which sounds a lot like a German tube believe it or not. (hard to even source today but I think Kevin Deal had some recently.)