The Timeless Allure of the Koss ESP-950 Electrostatic Stereophone

Published on Dec. 19, 2023, 8:04 a.m.

The Koss ESP-950 holds a special place in headphone history as one of the early pioneers in consumer electrostatic headphone technology. First released in 1991, the ESP-950 brought the breathtaking soundstage and accuracy of an electrostatic transducer to the masses in an affordable package. Over 20 years later, it is still coveted by audiophiles as a reference headphone for classical, jazz, and acoustic recordings.

Overview

The Koss ESP-950 Electrostatic Stereophone stands out with its featherweight comfort, open-back circumaural design, and electrostatic drivers that reproduce music with unbelievable realism. Handcrafted in Milwaukee, USA, each pair reflects Koss’s commitment to quality and lifetime customer service. While the plastic build quality leaves something to be desired, the sound quality is unparalleled in its price range.

Key Features

The Koss ESP-950 Electrostatic Stereophone is distinguished by:
- Electrostatic Drivers: Exceptional clarity, accuracy, and detail.
- Wide Frequency Response (8-35,000 Hz): Captures the full range of human hearing.
- Energizer (E/90): Dedicated amplifier for optimal driver performance.
- Lightweight Comfort: Pivoting ear cups and adjustable headband.
- Limited Lifetime Warranty: Peace of mind for your investment.

Koss ESP-950 Electrostatic Stereophone

Design - Retro Styling

The Koss ESP-950 Electrostatic Stereophone sports a retro aesthetic with large, oval earcups hung from a lightweight plastic headband. Pivoting earcups and adjustable height ensure a custom fit. Packaged in a leather zipper case with battery pack and cables, the whole setup oozes 1970s hi-fi charm.

Sound Quality - Unrivalled Clarity

At the heart of the Koss ESP-950 Electrostatic Stereophone’s brilliance lies its electrostatic drivers. The diaphragm is an ultra-thin 1.5 micron polyester film coated with a conductive material. When powered by the dedicated E90 energizer, it achieves an incredible frequency response from 8 Hz to 35 kHz. The result is a soundstage of startling depth and width, with no listening fatigue. From the deepest bass tones to soaring treble, audio is rendered with lifelike accuracy.

Electrostatic Transducers: A Sonic Revolution

The heart and soul of the ESP-950 lies in its electrostatic transducers. Unlike traditional dynamic drivers, electrostatic transducers use a thin, electrically charged diaphragm suspended between two perforated metal plates (stators). When audio signals pass through, the diaphragm vibrates, producing sound waves. This design results in incredibly fast transient response, minimal distortion, and unparalleled accuracy across the frequency spectrum. The ESP-950’s electrostatic drivers are meticulously handcrafted in the USA, ensuring that every pair delivers a sonic experience that’s truly extraordinary.

8-35,000 Hz Ultra-Wide Frequency Response: The Full Spectrum of Sound

The ESP-950 boasts an astounding frequency response of 8-35,000 Hz, far exceeding the range of human hearing (20 Hz - 20,000 Hz). This wide range ensures that every nuance of your music is faithfully reproduced, from the deepest bass notes to the most delicate high-frequency details. Whether you’re listening to a symphony orchestra or a solo piano, the ESP-950 captures the full spectrum of sound with breathtaking clarity and precision.

E/90 Energizer: Powering the Electrostatic Symphony

Electrostatic headphones require a dedicated amplifier, or energizer, to drive their unique drivers. The ESP-950 comes with the E/90 energizer, a powerful and meticulously engineered amplifier designed specifically for electrostatic headphones. The E/90 delivers the high voltage necessary to drive the electrostatic transducers, ensuring optimal performance and sonic excellence. Its 1.6Hz - 50kHz frequency response, -100dB signal to noise ratio and voltage amplification of 60dB guarantee that the ESP-950 performs at its peak potential.

Pivoting Ear Cups and Adjustable Headband: Comfort Meets Customization

Koss understands that comfort is key to a great listening experience. The ESP-950 features pivoting ear cups that adjust to the contours of your head, ensuring a secure and comfortable fit. The adjustable headband further enhances comfort, allowing you to customize the fit to your preferences. Whether you have a small or large head, the ESP-950 will adapt to your unique shape, providing hours of comfortable listening.

Uses - Hi-Fi Bliss

The open-back design and pinpoint accuracy of the Koss ESP-950 Electrostatic Stereophone excel at portraying the space and dimensionality of a live performance. They are especially magical with small ensemble jazz, chamber music, and vocalists. The lightweight comfort also makes them ideal for prolonged listening sessions. For discerning audiophiles seeking hi-fi bliss, the Koss ESP-950 Electrostatic Stereophone delivers an unforgettable listening experience.

Koss ESP-950 Electrostatic Stereophone

Use Cases:

The Koss ESP-950 electrostatic headphones are ideal for:
- Critical listening to high-resolution music in optimal conditions
- Experiencing the intimacy of vocal performances and acoustic instruments
- Prolonged listening sessions thanks to their lightweight comfort
- Obtaining a breathtakingly realistic concert hall perspective
Koss ESP-950 Electrostatic Stereophone

User Feedback Analysis:

Revered by audiophiles as one of the pinnacles of electrostatic headphone design, the Koss ESP-950 Electrostatic Stereophone evokes fervent admiration for its beguiling accuracy. Many deem its transient response nothing short of revelatory, catapulting listeners into a transcendent sphere.

Myriad owners extol the Koss ESP-950 Electrostatic Stereophone’s preternatural realism, as though vanishing the boundaries between recording and live performance. The expansive headstage paints sonic landscapes with holographic dimensionality, casting instruments and vocals around the listener. Treble earns consistent praise for its smooth, airy extension devoid of strident edginess. Midrange clarity likewise elicits awe, revealing microscopic nuances in timbre and texture.

Bass authority garners mixed impressions, with some wishing for visceral impact while others applaud its taut precision. Yet for certain genres like classical, jazz, and vocals, owners proclaim tonal balance that simply sounds “right.” The featherweight comfort also wins universal acclaim for all-day, fatigue-free listening.

Beyond sonics, build quality and component longevity remain points of contention. The plasticky aesthetic offends some, though functionality outweighs form for most devotees. The energizer may require troubleshooting, sending perfectionists into paroxysms yet scarcely deterring satisfaction for average listeners.

Nonetheless, flaws fade amidst overwhelming praise of the Koss ESP-950 Electrostatic Stereophone’s auditory splendor. Many deem it a priceless portal into musical truth, and some proclaim it the singular greatest headphone they’ve ever heard regardless of cost. This transcendent listening experience elevates the Koss ESP-950 Electrostatic Stereophone into rarified air, cementing its iconic status among electrostatic transducers.

Pros:

Breathtaking realism and accuracy
Electrostatic speed and precision
Smooth, fatigue-free treble
Intimate midrange
Holographic soundstage
Lightweight and comfortable
Handcrafted in the USA

Cons:

Bass lacks visceral impact
Plastic build quality
Energizer may require troubleshooting

Value:

For its discounted price, the Koss ESP-950 Electrostatic Stereophone delivers reference-level sound that rivals headphones costing many times more. The electrostatic drivers achieve lifelike clarity and realism unmatched in its price tier. Combined with handcrafted quality and a lifetime warranty, the Koss ESP-950 Electrostatic Stereophone is an incredible value for serious audiophiles.

Conclusion

The Koss ESP-950 Electrostatic Stereophone stands out as an electrostatic classic, delivering breathtaking sonic accuracy and a magical listening experience. For audiophiles searching for the holy grail of headphones, the Koss ESP-950 Electrostatic Stereophone warrants an audition to appreciate its brilliant craftsmanship and timeless allure.