From the Collings Website
The Traditional Series or "T Series” guitars reflect Bill Collings' return to his guitar making rootsand offer a new tonal variation on the distinctive Collings sound. Each T-Series guitar is built using animalprotein glue and a very thin, all nitrocellulose lacquer finish, making them exceptionally dynamic and
responsive. Bracing and tone woods are adjusted for weight and thickness to create a voicing characterized by warm, rounded highs and a present low midrange, while retaining a quick attack and strong projection.