Often times, interfacing your ham station to your processing chain becomes difficult at best dues to impedance mis-matches and audio level variations.  Employing hi-Z inputs on audio equipment can often times be a source of RF interference when operating the audio chain in a high RF environment, especially if the interconnecting cables exceed 6 feet in length.  It is much better to use a 600 ohm balanced audio system for interconnecting your audio equipment. 

With 600 ohm balanced audio, the length of the cable run is no longer a factor and RF interference is reduced considerably.  A computer is often used as a recording device in such applications.  Interfacing the sound card Hi-Z unbalanced inputs should be done with care in order to minimize RF interference problems as well as eliminating AC hum from the system.  Also, if you use your computer to drive low impedance balanced inputs, you need some sort of interface. 

This is where the TX-2 and PRO-1 come into play.  They are designed to interface computer sound card inputs and outputs to external equipment.  The TX-2 converts the computer sound card stereo unbalanced audio output to a Mono source which then is amplified from -10 DB to 0 DB and provides a 10K unbalanced output and a 600 ohm balanced output.

The PRO-1 is also a computer sound card interface which converts a unbalanced stereo input to a stereo 600 ohm balanced line level output. The technical specifications are suitable for use in professional audio applications.