TK Audio SP502


TK Audio SP502

Selectable output stages, electronically balanced or discrete Class A.

  • Sweepable high-pass filter, 30-400Hz, 12dB/oct.
  • Discrete DI audio path.
  • 70dB of clean gain.
  • Selectable saturation circuit for extra harmonics.
  • Discrete Class A output stage with Carnhill transformer.

SP502 is a new single slot 500-series preamp with a unique hybrid design including both vintage and modern circuits. A new transformerless input stage forms a clean and transparent front-end. Together with the two selectable output stages, you can get the low mid punch and thick sound associated with British Class A from the early 70s as well as a more modern clean tone from the 80s and 90s.

SP502 is also equipped with a saturation stage that can be selected to add some extra harmonics to the signal. The sweepable HPF from 30Hz to 400Hz allows precision crafting of the low end. A new function is that the instrument input can be routed directly to the output stage without passing the preamp stage (the saturation circuit and HPF can still be inserted). The DI direct mode together with the vintage Class A stage gives you a very nice discrete sound path for bass recording.

  • Power requirement: +130mA / -130mA
  • Input impedance: 2400 ohm
  • Instrument input impedance: 1Mohm
  • Max output level: electronically balanced +25dBu, Class A +24dBu
  • DI direct gain: +15dB
  • THD+N @ +20dBu electronic balanced output: 0.0008%
  • THD+N @ +20dBu Class A output: 0.007%
  • THD+N @ +20dBu saturation active: 0.9%
  • Frequency response electronic balanced: -0.6dB @ 80kHz
  • Frequency response Class A: -0.5dB @ 20kHz


  • Gain switch in 5dB steps: -15 to -70dB. +15dB to -40dB with -30dB pad selected
  • 48v phantom power
  • Selectable output stage: vintage transformer balanced Class A or electronically balanced
  • Sweepable high pass filter: 30-400Hz, 12dB slope
  • Saturation: inserts a saturation stage for extra harmonics after the input stage
  • Polarity switch
  • Direct: routes the instrument input directly to the output stage
  • In: activates the instrument input
  • Hi-Z input, instrument input with more than 1Mohm input impedance
  • Output level control
  • Illuminated switches (except for the phantom toggle switch which has a separate LED)

Specifications and components may be changed or updated without further notice.