Nagra IV-SJ — Precision tape recorder for sale

NAGRA IV-SJ COMPLETE MEASUREMENT SYSTEM — B&K 4133 pair, QSSF/QSLS, factory transport upgrades, original calibration sheets

Offered as a complete, working Nagra IV-SJ — the instrumentation variant of the legendary IV-S, built for precision noise and vibration measurement (customers ranged from NASA to Rolls-Royce). This is the full chain, not just the recorder, and it's rare to find one assembled this completely.

CONDITION — please read: The deck is fully functional in my own testing; it records and plays correctly. In fairness, it has NOT been professionally serviced or bench-checked — I'm describing only what I've personally verified, and it's priced as an honest owner-tested unit, not a shop-certified one. I'd budget for a checkup and calibration verification.

TRANSPORT: The tape path has been refined with genuine Nagra ruby guides and a Nagra tape scraper, plus an Athan precision roller. The original stock parts are included — run it as-is or return it fully to baseline, your choice.

MICROPHONES: A pair of Brüel & Kjær Type 4133 half-inch measurement microphones with their original calibration sheets (historical — recalibration recommended for precision work), feeding the Nagra via two QSJP adapters. Honest disclosure: in my test recordings one channel came in at a noticeably lower level than the other — could be the capsule, preamp, or a connection; I haven't isolated it. The pair is sold as-is and the price reflects it.

INCLUDED:

• Nagra IV-SJ recorder

• ATN-3 power supply

• QSSF balanced output module

• QSLS synchronizer

• 2× QSJP B&K preamp adapters

• 2× B&K Type 4133 microphones + original calibration sheets

• Original stock transport parts (guides, roller)

A coherent, complete IV-SJ measurement system in one purchase — these don't surface assembled like this often. Asking $7,800 OBO. Happy to provide more photos, video of it running, or answer any questions.