ProtoDAC TDA1387 X8 project

[hifinet]

I have been asked about a balanced output ProtoDAC.

Two ways:

1. Use a line level transformer to convert single ended to a balanced output. The transformer needs to be of high quality, for example Lundahl, Sowter, Jensen, Hammond, UTC, Peerless. The resulting performance can be very high quality, and an added benefit of using a transformer is isolation. This is probably the best method, but most expensive. This is a good article on how to do it.
   
2. Use an active device, a single ended to balanced converter. Here is one on eBay using the DRV134. No personal experience. 
   

The other method would involve a redesign. Use two TDA1387 X8 modules and a 74ACT86 logic IC. One module gets DATA (from I2S) and the other inverted DATA. The analog outputs will be 180 degrees out of phase. [Please see correction in post #198.]