Headphones — TEAC SR-L700MK2

The SR-L700MK2 is an open-backed electrostatic headphone from TEAC, built with an exceptionally high impedance typical of the electrostatic format. TEAC has a long history in Japanese audio electronics, and this electrostatic headphone represents a specialist category the brand has invested in alongside its more mainstream disc players and amplifiers.

Key specs that matter

Rated response is 7 Hz to 41 kHz, an exceptionally wide window characteristic of electrostatic driver technology, which typically achieves far faster transient response and wider bandwidth than a conventional dynamic driver. Maximum sound pressure level is 118 dB, a high figure ensuring adequate headroom even for demanding material. Sensitivity is 101 dB per milliwatt into an exceptionally high 145 kOhm impedance - this impedance figure is dramatically higher than any conventional headphone, since electrostatic drivers work on an entirely different operating principle requiring specialised amplification. Weight is 471 g, a moderate figure for the electrostatic category, which often produces notably heavier headphones than dynamic or planar magnetic designs of similar scale.

Sound and use context

Expect the extremely detailed, fast character typical of electrostatic headphones, with an open-backed design favouring soundstage over isolation - electrostatic drivers are widely regarded within the hobby as offering a uniquely transparent, low-distortion presentation unmatched by more conventional driver technologies.

Pairing

The 145 kOhm impedance requires a dedicated electrostatic energiser rather than a conventional headphone amplifier, a crucial and non-negotiable requirement, since a standard headphone amplifier simply cannot drive an electrostatic panel at all.

Alternatives

Other electrostatic headphone systems require the same dedicated energiser approach, differing in driver design and included energiser unit, so comparing the complete system - headphone plus energiser - matters more than comparing headphones alone across this category. Electrostatic headphones as a category demand a different kind of investment than a conventional dynamic or planar magnetic design, since the energiser unit itself represents a substantial additional cost and a permanent commitment to that specific ecosystem rather than a headphone that can simply be plugged into any existing amplifier. TEAC's specific approach to electrostatic engineering is worth comparing directly against the more established Stax ecosystem, which remains the best-known reference point within this specialist category.