Urei LA-3A Leveling Amplifier Pair #3739/3730 (Vintage)

The Teletronix / Universal Audio / Urei LA-3 Leveling Amplifier is a solid state version of the classic LA-2A tube optical limiter. Its early incarnation bore the Teletronix logo, presumably to show its connection with the LA-2A. Later iterations used the Universal audio name on the faceplate; in both cases the Urei logo was prominent.

The LA-3 has discrete circuitry and balanced ins and outs, along with adjustable input gain and threshold. it employs the same T4 opto cell for compression as found in the LA-2A.
Excellent for vocals, guitars, and mix buss. Great mid-range presence that engineers love. Can be very invisible, or more pronounced, due to continuously variable rotary controls. 'Peak Reduction' increases the sidechain gain - lowering the threshold and increasing compression - while 'Gain' is used to adjust the makeup gain.