Exlibris, there is a pretty significant difference between an Io Signature and the standard Io in that the Signature version delivers greater resolution, more neutral presentation and improved high frequency extension, among other things. Tube choices will certainly change the sonic signature as well. How this translates into what you may be hearing while listening only to the high level input of the standard Io with volume controls, I can't answer.
Albert Porter and others have noted that the addition of Callisto Signature as the linestage (compared to an Io Signature with volume controls) adds materially to overall dynamics and soundstage capabilities. I've not heard the comparison myself, but I trust Albert's comments.
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Albert Porter and others have noted that the addition of Callisto Signature as the linestage (compared to an Io Signature with volume controls) adds materially to overall dynamics and soundstage capabilities. I've not heard the comparison myself, but I trust Albert's comments.
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