Hi David12. To be candid here.... I have never heard your preamp in my own rig, however, I would like to point out that the typical 6922,6dj8 family of valves will traditionally last in excess of 3,000 to 4,000 hours of playing time in the CJ.Unless the tubes have become noisy or microphonic, I can't believe they would not test within spec for your preamp. NOS vrs current production tubes is a very subjective topic to be sure. One must also take into consideration the fact that almost all of the better modern tubed gear being manufactured today has been voiced with current production tubes. That is no guarantee the preamp will sound any better with good low noise NOS valves. In my experience: regardless of modern or vintage gear [preamps in particular],a strong testing low noise nos 6922 tube with tightly matched triode sections would inevitably win hands down in any given shoot out. Those that refuse to believe it are the people that [1] did a comparison with tired nos tubes [2]used nos tubes with poorly matched triode sections[3] used noisey or microphonic nos tubes [4] those that refuse to pay the current market value for a quiet and strong testing vintage Seimen,telefunken,Dutch Amperex[to name a few] 6922 family of tubes. Furthermore; sometimes the gain in sonics may not be justified given the ever increasing cost of good nos valves.I for one, believe the premium selected and matched Eh tubes are decent sounding in your preamp.... the russian military 6n23e's are considerably better [by a wide margin] and are always dead quiet to boot.They can be had for the same money with a little searching.I really like cellorover's anology with regards to establishing a benchmark for comparison. Do you have a tube tester? I would take bets that your stock tubes would test better than 90 percent. Perhaps, cellorover's suggestion of up grading to the mk2 version is in fact "the bigger bang for the buck". All the best in your journey.
New tubes for Conrad Johnson17LS Pre
Sigh... I know tube rolling has been discussed to death, but perhaps thats because it's a complex subject with no right answer (are'nt they all). Some say NOS tubes are snake oil and probably used anyway, others that they are indispensible. If there is a consensus it seems to be that the answer is equipment and system dependent. I use a Shanling CDT-100 and have found benefit in changing to Western Electric valves.
I bought the CJ from an Audiogon ad of course and am very happy with it. I use it with an LP12, the Shanling, an Aleph 3 Power amp, Living Voice Avatar speakers and Acoustic Zen cables. My query is, can it really be improved by replacing the Electro Harmonix 6922 valves supplied as stock and if so, with what? I do'nt really expect a consistent reply, it is too subjective a question, but any pearls of wisdom would be appreciated, thanks
I bought the CJ from an Audiogon ad of course and am very happy with it. I use it with an LP12, the Shanling, an Aleph 3 Power amp, Living Voice Avatar speakers and Acoustic Zen cables. My query is, can it really be improved by replacing the Electro Harmonix 6922 valves supplied as stock and if so, with what? I do'nt really expect a consistent reply, it is too subjective a question, but any pearls of wisdom would be appreciated, thanks