I've had the LL2.1 in-house for several months and tried it with a variety of NOS 6DJ8 family tubes. Along with the expected gain in 'air', timbre, etc., these older tubes (Valvo 7308s, Amperex Orange Globes, Telefunkens) deliver real improvement to image specificity versus the stock tubes.
Wrt 'dark sounding' - I understand how that can be an initial characterization some folks will use, but its not the way I'd describe the LL2.1. What I hear is a slight mid-bass lift (coupled with the preamp's excellent resolution) that yields deeper tonal colors - harmonics, overtones - in the mid-bass frequencies. In lower registers there is more emphasis on the notes' fundamental - deep bass is weighty and distinct but not as tonally nuanced. Its the contrast or difference between the tonal character of the mid-bass and low bass that that may lead to the 'darker' description. It takes a certain analytical cast to hear it this way - definitely not the direction the LL2.1 leads the ear, but that's how I parse it for now.
For its cost I think its a helluva preamp.
Wrt 'dark sounding' - I understand how that can be an initial characterization some folks will use, but its not the way I'd describe the LL2.1. What I hear is a slight mid-bass lift (coupled with the preamp's excellent resolution) that yields deeper tonal colors - harmonics, overtones - in the mid-bass frequencies. In lower registers there is more emphasis on the notes' fundamental - deep bass is weighty and distinct but not as tonally nuanced. Its the contrast or difference between the tonal character of the mid-bass and low bass that that may lead to the 'darker' description. It takes a certain analytical cast to hear it this way - definitely not the direction the LL2.1 leads the ear, but that's how I parse it for now.
For its cost I think its a helluva preamp.