Store › Blue Original Sigma Sound Studios T-Shirt Design (Blue) Blue Original Sigma Sound Studios T-Shirt Design (Blue) $25.00 Heather Blue Gildan t-shirt. High quality reproduction of the original 1970's T-Shirt with the iconic logo. Heather Blue Gildan t-shirt. High quality reproduction of the original 1970's T-Shirt with the iconic logo. Size: Select Size Medium Large XLarge Quantity: Add To Cart Added!