Is a rocket a rocket?

[jonp]

Hi,

I have a small batch of Russian military 6H23 with what appears to be a build date of November 1987. I'm using a pair of them in my X-Can V3 and they were certainly a significant improvement over the original JAN Philips (which lasted less than a month whilst these rockets have been going perfectly for 6 months).

Anyway, I see a lot mentioned about the Russian Rocket logo tubes, but it is as if there are Rocket tubes and there are Rocket tubes. Meaning I am wondering whether there are some which are supposedly in a completely different class for use in an XCan V3 versus other Rocket tubes.

Of course I would say my Rockets came with very good credentials and they were a big improvement. But that isn't saying much because listening to JAN Philips 6922's in an XCan V3 is like sleeping naked on a sandpaper matress.

Now comes the 7 month itch. I am pretty happy with my setup which comprises of a Sony PCM D50 as the source (24-96 vinyl captures), XCan V3 with the 1987 Rockets and Klipsch X10 (best headphone I have ever heard, but I have not heard high end Stax nor Sennheiser Orpheus).

I have a Tesla NOS gold pin 6922 from the 70s on order as well as those Japanese National 6922 made with the old Mullard tooling to try. I am only interested in trying NOS valves that are still available in good quantities and are reasonably priced. Those obviously qualify. Tungsram red label is a make I have heard good reports about, however they are now harder to find in quantity and are getting too high in price from reputable sources. So I thought whilst I am going to have the XCan opened one last time before the tubes actually blow, it might be worth a decent tube rolloing session.

Shoudl I just be content with my mid 80's Rockets? And are my Rockets good Rockets in any case? If I had to make mention of the weaknessess of the current Rockets it would be a smidgeon more grain in the midrange and upper midrange than is absolutely ideal and perhaps they are not the ultimate in resolution. But as I say, they are far better than what the amp came with.

[dejanm]

I am using in X-Can V2 Reflektor 6N23P-EV -> the same ones that PF recommended in his trube test. I never made such a test but I had the opportunity to listen X-10D V2 and X-Can V2 with several different tubes: Telefunken E88CC, Sovtek E88CC, ... and these Reflektor's are performing really well. Concerning the price: it is excellent value.

6N23P is another, cheaper version of the same and they can be found quite cheap on eBay. I never heard them nor I had the opportunity to compare them with anything else. On the Borbely site, though, you can find an article about his headphone amp. Design of this amp is very, very similar to the design of MF X-Can V2. Borbely measured THD of various 6922 tubes and found out that these Russian 6N23P have the smalles THD of all tubes that he measured. He is now delivering this amp with these Russian tubes.

You can read this article here:

www.borbelyaudio.com/pics/405borbely2506.pdf

I believe that you already have the tube that you are looking for. 6N23P seems to be a very good choice for very, very reasonable price. And obviously there are a lot of them around.

[PinkFloyd]

Your rockets are GOOD rockets probably from the Voskhod, Kaluga factory in Russia. Some of the early ones (60's 70's) come with A frame getters and I reckon these sound the dog's bollocks, I have a few pairs of these and you don't come across them that often

[dejanm]

This may help when identifying the tube ...

[jonp]

Hi,

Thanks a lot for the replies. My 6N23 valves are Voskhod. It will be interesting to compare them nonetheless, but it sounds like I already have an excellent valve for the XCan V3. Because they were such a big improvement over stock and because they were going fairly cheaply I bought about 5 pairs of them. Maybe that was an astute thing to do on reflection - I am noticing they are harder to find now than they were even 6 months ago.