This fun project has been on the shelf at JDS Labs for more than a year, postponed by long lead times of its high quality film capacitors and rare potentiometers. While you can probably find a software equalizer for your favorite music app, this hardware EQ is fully analog in nature, so it works with every app and avoids digital re-sampling. Kit pricing makes the EQ most affordable.
The JDS Labs 3-Band EQ has a wide adjustment range of about ±15dB for bass, mids, and treble. While the point of an EQ is to color your listening experience, the JDS Labs 3-Band EQ achieves low THD+N with its knobs in their neutral positions.
A muting relay eliminates turn on/off transients, and when the EQ is switched off, the original audio signal passes directly to the RCA output jacks.
Note: The first batch of this project ships with a thin PCB. Performance is normal, so this is merely a mechanical/cosmetic mixup. Initial pricing is discounted while supplies last. Enjoy!
3 Band EQ - DIY Assembly Guide
3 Band EQ - Frequency Response Curves
You will also need a 15VAC Power Adapter