Why does BAND 1 require 2 bands for 'OLD TUBE 1', 'OLD TUBE 3', and 'VINTAGE 3'?

The 'OLD TUBE 1', 'OLD TUBE 3', and 'VINTAGE 3' emulations are based upon a vintage EQ in which a low frequency shelf has two separate gain controls (one allows for positive gain and the other allows for attentuation). In order to emulate the EQ shelf in the most authentic way possible, it is necessary to gang the frequency control for the two gain controls. Consequently, the low frequency shelf requires two bands. This is illustrated in the screenshot below, showing the low frequency shelf occupying the first two bands.

It should be clear that this affects the creation of EQ hybrids on the Liquid Mix when using these special low frequency shelves. Any time you select the 'BAND 1: Shelf LF' for 'OLD TUBE 1' or 'OLD TUBE 3', two bands will be required. This means that if a single band from another emulation exists on an adjacent band, it will be removed in order to accommodate the second band of the 'BAND 1: Shelf LF'. In addition, if you select the 'BAND 1: Shelf LF' for band 7, it will be necessary to use both BAND 6 and BAND 7 to accommodate this filter. Both of these considerations should be taken into account when building hybrid EQs with the LF shelves of the on the Liquid Mix.