How to Build a Balanced Line Driver for audio testing.

How to Build a Balanced Stereo Line Driver for audio testing.

Testing an amplifier with a balanced input is easy if you have an audio source that has balanced outputs. If you don't, then testing is still possible if you simply short the 'cold' input to ground.
However, to fully test an amplifier with balanced inputs, you really need to test it with a balanced source, and this is sometimes a problem if you want to use a signal generator, or single-ended music source.

This simple project is meant to rectify that problem on my work-bench. It accepts an RCA input and produces a balanced signal through an XLR socket, with relatively little distortion or degrading of the signal.

Elliot Sound Products has an excellent write-up on this circuit, so have a look for yourself:
http://sound.whsites.net/project51.htm

See a series of 'Restoration Building Blocks' videos on detailed steps in the restoration process of tube radios and amps:
   • How to safely check the Power Transformer ...  


See also playlists on some other completed restoration projects.

PHILIPS BX750A:
   • Philips BX750A tube radio restoration - Pa...  

TELEFUNKEN OPUS 2114:
   • Telefunken Opus 2114 stereo tube radio res...  

SABA UW-175-Z 3D:
   • Saba UW 175-Z 3D tube radio restoration - ...  

GRUNDIG 1070:
   • Grundig 1070 tube radio restoration - Part...  

SCHAUB-LORENZ GOLDY 58 type 3020:
   • Schaub-Lorenz Goldy 58 type 3020 tube radi...  

BUSH VHF64:
   • Bush VHF64 tube radio restoration - Part 1...  

GRUNDIG 3060A:
   • Grundig 3060a tube radio restoration - Par...  

TELEFUNKEN OPERETTE 8:
   • Telefunken Operette 8 tube radio restorati...  

GRAETZ SUPER 171W:
   • Graetz Super 171W tube radio restoration -...  

LOEWE-OPTA MAGNET 3737W:
   • Loewe-Opta Magnet 3737W tube radio restora...  

BRAUN ATELIER 3:
   • Braun Atelier 3  

LOEWE-OPTA TRUXA STEREO 4741W:
   • Loewe-Opta Truxa Stereo 4741W  

GRAETZ COMEDIA 616:
   • Graetz Comedia 616 tube radio restoration ...  

SABA FREIBURG W2:
   • Saba Freiburg W2 (WII) restoration  

GRAETZ MUSICA 4R417:
   • Graetz Musica 4R417 restoration  


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