Charles1dad, I'm not familiar with every BAT product, but their SE-series tube preamps have offered optional parallel bundles of PIO film caps to bypass or replace select electrolytics. This option has not been available in VK tube amps, but REX may have it. However, an all-film power supply should surpass it, assuming no cost or size constraints. IME the power supply of a VK tube amp is enhanced with addition of film cap bypass and discrete Schottky rectifiers-- sounding cleaner and faster without sacrificing the smoothness of tubes. Ditto after replacing the stock PIO interstage coupling caps with V-Cap or my own ClarityCap MR. However some owners-- perhaps the OP is among them-- may prefer the silkier and prettier twinkle of the house sound.
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