Sony SCD XA5400ES tube rolling?

Just my 2 cents but $200 for a pair of Chinese 6SN7's seems a bit much even if the Sophia's do sound very good. There's still plenty of NOS available and most for less money.

Life expectancy would also be a concern for me. In addition to owning numerous versions of NOS 6SN7's, I still have several NOS Telefunken E88CC(6922) and ECC83(12AX7) tubes that have been used in five CAT preamps over more than a dozen years. Those tubes still test like new. The Sovtek's and Electro Harmonix that came with my first CAT didn't last 1500 hours. Yah, I know, we're talking 6SN7's but I'm guessing any good NOS will last waaay longer than anything produced today. Some of those old 6SN7's were rated for 10,000 hours!

Tubegroover, I agree with everything you said. Yep, Andy Bowman would be a good source and his prices are reasonable. Matching too is important and you want low noise.

There are many sources for the more common and inexpensive 60's & 70's RCA's, Sylvania's, Tungsol's and GE's and most of them sound much better than the current stuff. Besides Andy, there are quite a few other legitimate tube dealers who offer these tubes with matching available.

Much of my collection has been purchased on Ebay from sellers who have lots of mostly 100% positive feedback and who show test results, AND guarantee those test results or your money back. I also have a Hickok tester so I'm able to test everything I buy. If you can't test your own, then as I said, there are many legitimate dealers you can turn to.