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What exactly are these? I've got a book from a long time ago titled Low Legato Etudes for Tuba which is the first four Bordogni etudes transposed for low register work. Books 2&3 on the Encore site seem to be like what I have, which is what I want my program to order. Thanks for any info.

The change in title is confusing me. My vol 1 says Low Legato Etudes. The Encore site doesn't list a vol. 1 of Low Legato Etudes, just vols. 2&3. Is #1 out of print or has it been replaced by Low Register Studies.