Jax' place

Phono amplifiers with tubes

Every tube amplifier should have a phono stage or it would not be complete. I built the first version back in the year 1993. It was once designed by the late Jan Lodström who was a well known man in the DIY collective. I used this one until I started tweaking it in 2004.

picture of original riaa amplifier The original RIAA amplifier for moving magnet pickups.

Unlike most other designs this one does not use feedback to implement the RIAA standard frequency correction. It instead uses a passive network between the two stages. My schematic shows the tube 5751 while the original used ECC83/12AX7A. Deviation from the RIAA curve is at the most 1dB.