The Stax SRD-6SB is a signal transformer designed to operate Stax electrostatic headphones using a speaker amplifier. It provides a specific biasing arrangement, enabling compatibility with earlier models of Stax headphones that utilize normal bias. This model signifies a self-bias configuration, which means it generates the bias directly from the speaker amplifier's output. This differs from the standard Stax SRD-7 transformer, which continuously maintains the bias from the power line. The input connections for the SRD-6SB are set up for normal bias headphones, generally categorized into 6-pin connections, while it is also possible to modify these connections to accommodate other configurations. The SRD-6SB is recognized for its ability to deliver high-quality sound reproduction by adapting electrical properties to suit electrostatic headphone requirements. Additionally, repairability for the SRD-6SB is marked as 'not repairable', indicating that replacement parts are not available through official channels. Its design allows enthusiasts to explore modifications for enhanced performance, although caution is advised due to the potential risks involved in such alterations.
