Overview

The Audio-Technica AT-702 is a vintage open-back dynamic stereophone released in 1974 as part of Audio-Technica’s debut headphone family, the AT-700 series [1]. Audio-Technica entered headphone manufacturing that year by leveraging in-house transducer engineering originally developed for phono cartridges [1]. The AT-702 carries a single 47 mm full-range moving-coil dynamic driver per side in an open-back enclosure, with a fixed 5.0 m cable terminated in a 6.35 mm plug [2]. The model has been out of production for roughly 50 years, is absent from Audio-Technica’s current product index, and is now available only on the secondhand collector market at approximately 49.99 USD [3].

Scientific Validity

The manufacturer specification sheet lists a frequency response of 20 Hz – 20 kHz with no ±dB tolerance specified, and publishes no THD, S/N ratio, IMD, crosstalk, or frequency-response deviation figures [2]. No independent third-party measurements are available for verification. Without a tolerance band on the frequency-response claim and without any audibility-relevant distortion or noise figures, fidelity to the master source cannot be meaningfully evaluated in either direction, so the score is held at the midpoint pending independent measurement data.

Technology Level

The AT-702 is built entirely on 1970s-era commodity-grade analog technology. Audio-Technica designed and manufactured the unit in-house by extending its phono-cartridge transducer experience into headphone drivers [1], a positive factor for design ownership. Every constituent technology, however, is outdated by 2026 standards: the 47 mm full-range moving-coil dynamic driver, the open-back acoustic cup (a topology already established before launch by the Sennheiser HD414 in 1968), and the fixed 5.0 m cable with 6.35 mm plug [2]. No proprietary patent specific to the AT-702 is documented, no advanced motor topology or modern diaphragm composite is described, and no DSP, software, wireless, or digital integration is present. The product is purely analog and mechanical, no element is one a 2026 competitor would seek to license, and any current commodity headphone maker can trivially reproduce the topology, leaving no lasting competitive advantage.

Cost-Performance

This site evaluates based solely on functionality and measured performance values, without considering driver types or configurations.

The AT-702 is a passive wired stereo headphone with no DSP, no wireless, no ANC, and no microphone, currently available only on the secondhand market at 49.99 USD [3]. The cheapest equivalent-or-better product is the Koss KSC75 at 19.99 USD [4]. The KSC75 covers the same essential function set (passive wired stereo playback, no DSP, no wireless, no ANC, no microphone). On measurable performance, the comparator’s manufacturer frequency-response range is wider (15 Hz – 25 kHz versus the AT-702’s 20 Hz – 20 kHz with no ±dB tolerance), and the comparator additionally has documented third-party THD measurements (<0.1% midrange at 80 dB SPL) and a published third-party frequency-response measurement that the AT-702 lacks entirely [5]. Because the AT-702 has no third-party measurements and no published frequency-response tolerance, the comparison is provisional; the Koss KSC75 is at minimum equivalent on every published axis and demonstrably better on those independently verified.

CP = 19.99 USD / 49.99 USD = 0.40

Reliability & Support

Audio-Technica’s standard 2-year limited warranty applies only to current products from authorized dealers, and the AT-702’s original warranty has long since lapsed; no manufacturer warranty applies to secondhand units obtained today. The model is absent from Audio-Technica’s current service-parts catalog, no AT-702-specific support pages or service bulletins are listed by the manufacturer, and parts supply through manufacturer channels is effectively ended after roughly 50 years out of production. Offsetting these negatives, the design itself is simple and inherently durable, with a single passive dynamic driver per side, no electronics, no firmware, and no moving parts beyond the headband adjustment, and surviving units continue to be documented as functional on the secondhand market [3]. No formal recalls or systemic defects have been documented, and no statistical RMA or MTBF data for the AT-700 series is published.

Rationality of Design Philosophy

Audio-Technica publishes no AT-702-specific design-philosophy statement, white paper, or measurement target [1], and the manufacturer specification sheet provides no ±dB tolerance for the frequency-response claim and no THD, S/N ratio, or IMD figures [2], so audibility-oriented intent cannot be verified from documentation. Within the practical constraints of 1974 consumer headphone design, however, choosing a simple open-back dynamic architecture with a single full-range driver, passive operation, and direct 6.35 mm connectivity is a function-first and manufacturable approach rather than an occult or claim-driven one [2]. At the same time, no measurement-led optimization process is documented, and no evidence shows a philosophy centered on quantified fidelity improvement. The result is a slightly-below-neutral score: rational in its original period context, but weakly evidenced by modern scientific-documentation standards.

Advice

The AT-702 is a 50-year-old discontinued passive headphone with no manufacturer warranty, no service-parts supply, no third-party measurements, and only a partial manufacturer specification (frequency-response range with no ±dB tolerance, plus maximum input power) available for fidelity assessment [2]. At a representative 49.99 USD secondhand price [3], the current-production Koss KSC75 at 19.99 USD covers the same essential passive wired stereo function set, has a wider manufacturer frequency-response range, and adds documented third-party THD measurements (<0.1% midrange at 80 dB SPL) that the AT-702 cannot match [4][5]. For a buyer whose objective is fidelity to the source, the AT-702 offers no measurable advantage over the cheaper, currently supported alternative. Acquisition is rational only on collector or historical grounds, where audio performance and manufacturer support are not the deciding factors.

References

[1] Audio-Technica - 50 years of headphone excellence (corporate retrospective documenting AT-700 series 1974 launch and Audio-Technica’s transition from phono cartridges into headphones) - https://www.audio-technica.com/en-us/headphones-50th-anniversary - accessed 2026-04-28

[2] Sopp blog - audio-technica AT-702 (collector reproduction of the Audio-Technica original spec card: 47 mm dynamic driver, open-back, 20 Hz – 20 kHz, 200 mW max input, 250 g, 5.0 m fixed cable, 6.35 mm plug, 1974 release) - http://sopp06.blogspot.com/2014/03/audio-technica-at-702.html - accessed 2026-04-28

[3] PicClick / eBay sold listing - “RARE VINTAGE AUDIO TECHNICA AT-702 STEREO HEADPHONES Working” (sold price 49.99 USD, used working condition, secondhand market reference) - https://picclick.com/RARE-VINTAGE-AUDIO-TECHNICA-AT-702-STEREO-HEADPHONES-Working-322238595335.html - accessed 2026-04-28

[4] Amazon US - Koss KSC75 Portable On-Ear Clip Headphones (current new listing, approximately 19.99 USD) - https://www.amazon.com/Koss-KSC75-Portable-Stereophone-Headphones/dp/B0006B486K - accessed 2026-04-28

[5] DIY-Audio-Heaven - KSC75 measurement page (frequency-response and harmonic-distortion measurements; 2nd-harmonic THD <0.1% midrange at 80 dB SPL) - https://diyaudioheaven.wordpress.com/measurements/koss/ksc75/ - accessed 2026-04-28

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