tube upgrade for first sound


Has anyone been able to improve on the stock tubes in the First Sound preamps? I was thinking about trying the Russian 6H23. Any thoughts? thanks
84audio
Paul, Did you end up with a First Sound preamp? I ended up with a Supratek instead of the H-Cat. Bob
Hi Bob
First Sound it is! Don't have it yet. Should be acouple of weeks. I'm keeping my fingers crossed. :-) It meets all of the technical issues I have regarding DC leakage and all. I've tried 2 other tube pre's as well. I've been climbing the ladder. This is the end for me, no matter what. I hope this is "the one". :-) How is your Supratek?
oldpet tell us more about your system. There are a bunch of highly satisfied FS oweners here - we want to know more about your rig.

Also, allow the thing to break in at east 3 weks before coming to any conclusions - AND REMEMBER IT INVERTS PHASE, so you need to account for that.
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I can't hear the difference either, and there's the POV that half of all recordings are inverted anyway. But I have my speakeer leads reversed at the amp just the same as Emmannuel Go is quite insistent about this.

And Paul, as many have mentioned, plug it straight into the wall. After a while, you will want to play with aftermarket power cords.