High Performance Audio Output Transformer from the renowned Lundahl Transformer company.
The LL1539 is an audio output transformer for balanced drive. 
In LL1539, the winding arrangement is such that (properly connected) the secondary windings are surrounded by cold (neutral) parts of the primary windings. 
This reduces the effect of the capacitance between the primary and the secondary windings. 
Thus, primaries should always be connected as in the application example below, with or without current feedback drive (negative source impedance) 
Please allow 3-4 weeks for delivery until we have stock