500 Series Output Transformers

500 series type processing is wildly popular because of the almost unlimited number of combinations of different types of devices by different manufacturers that can be loaded into one frame. About the only fly in the ointment are the issues created by the shared power supply. To deal with the possibility of ground loops, output transformers are often used to provide isolation and usually some additional gain.
The CT-2385 is Crimson’s standard 500 series style output. It features 4 identical windings that are wound together (quad-filar). 2 can be connected in parallel for minimum resistance in the input, and 2 are connected in series for 6 dB of gain in the output. An iron core provides a vintage sound, and a copper band around the coil reduces noise.
Many custom variations are available for OEM applications. Different core materials including high and low nickel alloys, and combinations of iron and nickel. Other winding techniques including tri-filar and special Litz wire can be used. Also mechanical variations such as lead placement and inter-connection of the coils are available.