J. I. Agnew

Engineering Consultant

J. I. Agnew is a Greek-American engineer, specializing in precision mechanical engineering and high-end audio electronics, often applied to analog recording and reproducing equipment.

He is an internationally recognized authority in the field of analog sound recording and mastering, regularly restoring, repairing and modifying vintage disk recording lathes and tape machines, designing and manufacturing new parts for them, designing and constructing custom equipment for professional audio facilities, while also engineering fully analog recordings and cutting master disks for vinyl record manufacturing.
Furthermore, he is actively involved in research and development projects, designing and prototyping high performance electronic circuits and precision mechanical assemblies commissioned by various concerns worldwide.

J. I. Agnew was educated in Greece and England, was awarded a scholarship for his doctoral research at the University of Sheffield and spent a few years teaching at the same institution. He has frequently presented his work in conferences, seminars and workshops in several countries around the world.

In 2014, along with Sabine Steldinger, he founded Magnetic Fidelity, which was to become a world-class mastering facility with a focus on analog media. Their life and work became the subject of a full-length documentary film, directed in 2017 by Elina Verykiou and Vasilia Koutsiana, titled "Magnetic Fidelity: A Love Story", screened in various international film festivals and broadcast on national television in Greece.

In 2019, his work in recording and mastering Naxatras III (the third full length studio album by popular rock group Naxatras), using exclusively analog equipment, brought home the prestigious "Analog Audiophile Recording" award at the Rocky Mountain International Hi-Fi Press Award, at the Rocky Mountain International Audio Fest, in Denver, Colorado.
J.I. Agnew is currently also a staff Writer for Copper, an audio magazine edited by Frank Doris (formerly of the Absolute Sound) and published by Paul McGowan (CEO) of PS Audio. J.I. is contributing a regular column titled "Revolutions per Minute", discussing "anything that spins" (usually related to vintage audio equipment)!
His daily work activities range from designing industrial machinery from first principles, operating precision machine tools to make parts to extreme degrees of accuracy, operating electronic, mechanical and optical measurement instruments, matching vacuum tubes to exacting specifications, and getting his hands greasy repairing and adjusting vintage machines, all the way to doing studio work, technical and creative writing, researching audio and industrial history and is even known to operate a forklift truck and crane if a big semi rig is waiting outside and nobody else is around.

He is a full member of the Audio Engineering Society, the American Society for Mechanical Engineering, the Institute for Electrical and Electronics Engineering, the American Society for Precision Engineering and the Tube Collectors Association.


Key Skills:

Mechanical Engineering

  • Micromachining
  • Precision Machine Tool Design, Restoration and Operation
  • Transport System Design for Audio Equipment
  • Mechanical Measurement Instrument Design, Calibration and Operation
  • Precision Metrology
  • Precision Mechanical Assembly Design
  • Precision Bearing System Design
  • Structural Welding
  • Design for Manufacturability with Geometric Dimensioning and Tolerancing
  • Coil Winding Equipment Design and Operation
  • Restoration, Adjustment and Repair of rare undocumented mechanical equipment

Electronics & Electrical Engineering

  • High Performance Circuit Design and Prototyping
  • Vacuum Tube Electronics
  • Precision Transducer Design
  • Transformer and Inductor Design
  • Measurement and Calibration
  • Vacuum Tube Testing and Matching
  • Custom Equipment Design
  • Laboratory Measurement Instruments
  • Audio-Grade Electrical Installations
  • Off-Grid Power and Renewables for Audio
  • Control and Automation Systems
  • Communication Systems
  • Restoration and Repair of rare undocumented electronic equipment

Audio Engineering

  • Analog Disk Recording and Mastering Systems
  • Analog Tape Recording and Mastering Systems
  • Tape Duplication Systems
  • Tape Editing
  • Vinyl Record Manufacturing
  • CD/DVD Manufacturing
  • Acoustics
  • Studio Design
  • Custom Audio Equipment
  • Full Range Monitoring Systems
  • Audiophile Listening Rooms and System Design
  • Testing, Calibration and Measurements
  • Audio Transducer Design
  • Electronic Musical Instruments


  • Microscopes
  • Optical Measurement Instruments
  • Photographic Equipment

Industrial Equipment

  • Air Compressors, Vacuum Pumps and Pneumatic Installations
  • Hydraulic Systems

Automotive Technology

  • Internal Combustion Engine Overhaul Procedures
  • Classic Vehicle Restoration
  • Automotive Electrical System Design
  • International Driving Experience, Overland Travel

Information Technology

  • UNIX, BSD and GNU/Linux Operating Systems
  • C/C++, Python, Shell Scrips, BASIC, HTML/CSS, SQL
  • Max/MSP & Pure Data
  • Internet Radio Broadcasting
  • TeX Typesetting
  • Vintage 8-bit Computers

Language Skills

  • English (Native, Cambridge Proficiency Certification)
  • Greek (Fluent)
  • German (Basic)
  • Serbocroatian (Basic)

Other Skills

  • Technical Writing, Reports and Documentation
  • Classical Music Education (Guitar & Piano)
  • Rigging and Lifting Equipment Operation (Forklifts, Cranes)