Schiit Lokius 6-Band Balanced Tone Control Equalizer (Silver)

You can make your system sound the way you want. Deep bass? Absolutely. Sparkling highs? Yes again! Go ahead—treat yourself to your perfect sound. Lokius transforms your system without getting in the way, or making itself known.
Bands: 20Hz, 120Hz, 400Hz, 2kHz, 6kHz, 16kHz.
Adjustment: +/-12dB at 20Hz and 16kHz, +/-9dB at 120Hz and 6kHz, +/-6dB at 400 and 2kHz.
Lokius integrates with any system, large or small, speaker or headphone, balanced or single-ended, for complete flexibility.
Product is supplied with a 110–120VAC US power supply suitable for use in the United States, Canada, and Mexico. This power supply will not work in 220–240VAC countries. Lokius is designed and built in the USA.