HAPI1 Posted: marca, 1st 2010

Discrete Op Amp

2LAIV is a stereo optocompressor built using discrete components. The input stage is an ultra fast op-amp, the NE5532AN. This version was specially prepared for audio applications. The output transformer is driven by a complementary pair of BD139/140 transistors known well from the 1176 compressor. The secret of this device is in the Electroluminescent (EL) panel used in the gain reduction path. The Silonex photo-resistor was used first in the legendary T4B photocells, in turn used in the legendary L2-2A compressors. Controlling the compression doesn’t require any signal conversion, which makes the compression unique. The characteristic sound is described by many users as quasi-intelligent. Going deeper into the subject the answers lie in the Threshold settings. It is no secret that optocompression works best for vocals, guitars and bass. As in any vintage device, manipulation is minimized: Output, Threshold, and Ratio. The character of the sound is similar to the 1176, but without the characteristic pumping. This is an outcome of the EL compression and optimally set attack and release. The modern solutions of +/- 18V allow even greater device dynamics. The Output of the 2LAIV can work with converters set to up to +24dBU.