The signal coming out of a phono cartridge is tiny—measured in millivolts for a moving magnet and microvolts for a moving coil. That's hundreds or even thousands of times smaller than the line-level signal your preamp expects. The phono stage's job is to amplify that signal cleanly, apply the proper RIAA equalization curve to restore the frequency balance, and do all of this without adding noise or distortion that would bury the music.
It's a harder job than it sounds. You're amplifying a signal so small that even the thermal noise from the resistors in the circuit can become audible. Every bit of hum from the power supply, every stray RF signal floating through the air, every mechanical vibration in the chassis—all of it gets magnified along with the music. That's why phono stages demand obsessive attention to grounding, shielding, power supply design, and component selection.
We learned this decades ago when we built our first phono preamp at PS Audio. It's actually how the company started—a standalone phono stage in a cigar box, powered by batteries to avoid any AC noise. That little unit taught us that if you get the fundamentals right—clean gain, proper equalization, and a noise floor low enough to stay out of the way—you're at least off to a good start.
But there's so much more. How do you manage to make magic with vinyl? Is the EQ curve passive or active? Discrete or chips? How important is feedback? What makes some phono stages soooooo much better than the others?
50 years of designing them and we've learned a lot.
When a phono stage gets it right, vinyl playback stops feeling like a compromise and starts feeling like magic. The record's surface noise separates from the music, the soundstage opens up, and suddenly you're hearing into the music in a way that reminds you why people still love spinning records.
