smokenjo25 posts05-08-2018 6:42pmhas anyone try PSVANE tubes in their 350
I’m using PSVANE 12AX& & 12AT7 and the original Shuguang KT88s in my 180’s which drive Avalon Eidolons. The line level signal is from a Reflection Audio OM-1 battery powered preamplifier.
In my experience the system context can have a greater influence on the outcome of a resulting tube change not to mention ones personal taste in a systems overall presentation.
Pardon my ability to convey my sonic differences. In my system I found the PSVANEs increased a sense of space or openness and a slightly deeper stage. An overall refinement that one might associate, but not quite as dramatic as, a phono cartridge upgrade.
Regarding the Shuguang KT88s used in the Bob Carver VTA 180s:
Going on five years of ownership I’ve only needed to replace one output tube due to a physical bump that mechanically loosened the bottle from the base which dramatically lowered its output according to the amplifiers own bias test method. After testing the remaining five tubes as well as the new replacement tube the bias setting remained at the same point as the initial setting after the amplifiers initial insulation years ago. I was unable to hear any noticeable improvement with the addition of the one new tube.
By comparison at this point in usage I had preformed numerous bias adjustments and changed full complements of tubes in my Marantz 8Bs and my MFA D75 exhibiting noticeable improvements in presentation as a result of their replacement.
From the 350 manual: ["FUSES
The rear panel line fuse is a 6 ampere (3 ampere for 240 volt operation), fast blow type, and should be replaced with the same type and rating if it ever needs replacing. Do not, under any circumstances, use a "slow-blow" fuse here.
The (rear panel) vacuum tube cathode fuse is a 1.0 ampere and should be replaced with the same type and rating. If the fuse blows during bench testing, it may be temporarily replaced with a 1.25 or 1.5 ampere fuse.
Normally, a 1.0 ampere fuse will be perfect for music because the peak-to-average power ratio of speech and music is about 10:1. If you find that the 1.0 amp fuse blows with music, you may replace it with a 1.25 ampere fuse, or even a 1.5 ampere unit."]