Technics / SU-9400 / 1970s

Technics SU-9400 Integrated Amplifier

The Technics SU-9400 is a vintage stereo integrated amplifier released around 1975 by Panasonic/Technics as a Japan-market flagship model (originally priced at ¥148,000). It combines technologies from the acclaimed SU-9200 and SE-9200 separate components into a single chassis. • Advanced Phono Stage: Features switchable input impedance (resistance and capacitance stages) for fine-tuning cartridge matching. • Control & Preamp Design: Equipped with a 26-step attenuator volume control, low-distortion Class-A SEPP pre-stage, and an 11-contact NF tone control circuit. • Power Supply: Built with ±42V constant-voltage power supplies and a large 10,000 µF filter capacitor to reduce inter-channel interference.

Technics SU-9400 Integrated Amplifier — photograph 2

Technics SU-9400 Integrated Amplifier — photograph 3

Technics SU-9400 Integrated Amplifier — photograph 4

Technics SU-9400 Integrated Amplifier — photograph 5

Restoration notes

Fully disassembled and cleaned. Inputs cleaned. All capacitors on all boards replaced, including filter capacitors. (I only use Nichicon, Panasonic, Kemet and WIMA capacitors) New diodes in power supply and amplifier circuits. Pre-driver and differential transistors replaced. Final output transistors pulled and cleaned along with new thermal grease and pads applied. All controls disassembled and cleaned/conditioned. New lamps throughout. Circuit boards inspected for any cracking, burning, etc.

Condition

SOLD