The rear panel also features variable stereo linking for two units, as well as a "Pre-emphasis" control which gives you a sweepable high-pass filter in the sidechain to let low frequencies go through uncompressed. All-discrete circuitry with custom Cinemeg input and output transformers, primo vacuum tubes and a Kenetek opto cell provides an incredible vintage tone, giving a great big hug to any signal that passes through. Stunning on bass, acoustic guitars and vocals, the WA-2A is also super affordable, putting classic sound into any studio without having to sell any vital organs.