Stax SR-L700 Mk2 Electrostatic Earspeakers / SRM-323S Energiser

Here we have a complete headphone system with a difference – they’re not headphones – Stax call them Electrostatic Earspeakers and being an electrostatic design they require an energiser unit to drive them. The system comprises of a pair of SR-L700 Mk2 Earspeakers together with an SRM-323S Energiser. They are in very good condition, come in original factory packaging, along with manuals, mains, headphone, and interconnect cables, plus, our normal three month warranty.
Stax Say….
SR-L700 Mk2 Earspeakers
The first SR-Lambda series was introduced 36 years ago and it has further developed into a new-generation SR-Lambda with its newly designed enclosure – the new SR-L700 Mk2 advanced-Lambda series Earspeaker.
The SR-009 hand selected thin-film diaphragm as well as fixed electrodes machined through three-layer stainless etching using heat diffusion has been employed for the SR-L700 Mk2 sound element. Thus, rich deep bass response, delicate high frequency and soothing mid-range has been achieved in a balanced sound.
The headband (ARC) assembly of the SR-L700 is equipped with 10-click slider mechanism for head pad height adjustment adopted from SR-009. Once adjusted, the slider always maintains its optimal position to make readjustment unnecessary. This enables you to enjoy hours of pleasant music listening with utmost comfort.
6NCu high purity 99.99999% copper wires are employed for the core wires plated in silver coating. The whole cable uses the conventional wide format parallel structure to lower the capacitance between each wire and finished with the most suitable structure to drive the Earspeaker.
New earpad design is carefully hand crafted with genuine lamb leather for utmost comfort for hours of music enjoyment as well as sound performance.
The Mk2 models have adopted the cable-exchangeable structure as well as the case holder made from aluminium aiming at user-friendliness and wearing comfort when listening to music.
The exchangeable cable structure of recent trend for high-quality headphone has been employed. This enables the prospective correspondence to a high-definition cable, and the easy maintenance to sudden disconnection, thus improving the user-friendliness of earspeaker.
The change of material has enabled the mechanism design with more high flexibility. In the MK2 models, changing the case holder design from conventional linear style into moderate curve form produces the effect that ear pads fit more naturally on both-sides-of-the-head part. Moreover, the curve form gives high rigidity and prevents from generating unnecessary distortion or twist at the time of wearing, resulting in the great improvement of fit feeling. In an open-air type earspeaker, the degree rise of adhesion at the time of wearing greatly contributes to the improvement of low-frequency reproduction.
Specifications
Type: push-pull electrostatic sound element, open-air type enclosure
Sound Element Shape: oval
Frequency Response: 7 – 41,000 Hz
Electrostatic Capacitance: 110 pF
Impedance: 145 kΩ
Sound Pressure Sensitivity: 101 dB
Bias Voltage: 580 V DC
Cable: parallel 6-strand, low-capacity wide cable
Cable Length: 2.5 m full length
Attached Cable Conductor: 6N (99.9999%) OFC + silver plated annealed copper wire
Ear Pad: genuine sheep leather (skin touching portion), artificial leather (surrounding portion)
Weight: 371 g
SRM-323S Energiser
Features:
High-quality non-magnetic audio grade quality resistors are employed for the main circuit, greatly improving tonal quality
Emitter-follower circuit in the output stage uses high voltage bipolar transistors, which ensures low output impedance, resulting in high drivability and wide high-frequency dynamic range
Traditional balanced circuit and simple 2-stage amplification has been adopted for the input stage. Using low-noise high-quality dual FETs, ensures the best sound reproduction
Class-A all-stage DC amplifier circuit configuration eliminates coupling capacitors throughout the signal path
A single RCA input is equipped with parallel out, which directly feeds the incoming signal
Two 5-pin output sockets are connectable to all pro-bias compatible earspeakers.
Specifications:
Frequency Response: DC – 60 kHz
Rated Input Level: 100 mV with 100 V output
Maximum Input Level: 30 V rms with volume at minimum setting
Amplification: 60 dB (x 1000)
Total Harmonic Distortion: max. 0.01% (1 kHz / during 100 V rms output)
Input Impedance: 50 kΩ (RCA)
Maximum Output Voltage: 400 V rms / 1 kHz
Standard Bias Voltage: DC 580 V
Power Voltage: AC 120 V – 240 V ± 10%, 50 to 60 Hz
Power Consumption: 30 W
Dimensions: 150 (W) × 360 (D) × 100 (H) mm
Weight: 2.9 kg