Heritage Audio GRANDCHILD 670 Tube Vari-Mu Stereo Compressor for 500 SeriesGlue your mixes and busses together with the distinctive character of tube driven variable mu compression, using the GRANDCHILD 670 from Heritage Audio, a two space 500 series stereo compressor outfitted with four 6BA6 (5749) NOS tubes, three exclusively designed transformers (one per channel and and one for the sidechain), and the select components and circuitry necessary to capture that sought after warm, analog sound. The Fairchild for the Rest of