Unfortunately, you can't use custom text encodings. There are only two text 
' encodings 
supported by ID3v23 and Unicode is the one used for extended characters. (...)
That's not a limitation of UltraID3Lib or my knowledge of the BinaryWriter 
' overloads;
it's a specification of the ID3 v2.3 tag standard as described on www.id3.org.

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"There's never enough time to do all the nothing you want."
(Calvin and Hobbes)