Stax SRS-2020 Basic System

The budget electrostatic headphone

By Michael Jones

November 2003

Stax SRS-2020 Basic System II. $1030

Excluding the Walkman and Discman users, headphone listeners use their headphones for one of two reasons: in order to hear deeper into a recording or because it is the only way they can get to listen to their music. Whichever group you may fall in to, the Stax Basic System 2 may be for you.

Memphis soul stew

It’s ironical that with a modest set of headphones, a listener can hear more of a recording than with even an expensive pair of audiophile loudspeakers. One (non-Stax) hi-fi retailer I know describes his regularly-purchased top headphones as “the best $20,000 speaker you can buy for $600.” The small details of a recording that are easily audible on headphone can easily get lost in the speaker room interface, or because of the continual background hub-bub of noise in modern society.

Then there’s that group of people who can’t listen to music through their speakers as much as they like. Often this is because of other family demands (“Don’t play the stereo dear, Shortland Street is on”). Or they flat and others don’t appreciate their choice in music.

Respect yourself

No relation to the famous Memphis soul music record label of the same name, Stax of Japan have been equally famous in audio circles for their electrostatic headphones. (Stax have also produced electrostatic speakers and a fine class-A amplifier).

Unlike more common headphones, which use magnets and coils to drive a miniature speaker, an electrostatic headphone uses electrostatic force to move a thin diaphragm to which a DC voltage of 580V is applied. That movement creates sound.

So why have an electrostatic headphone at all? The reasoning is similar to electrostatic speakers. A thin diaphragm, driven uniformly over its entire surface, should respond more quickly and more delicately to the musical signal.

Soul limbo

The 2020 Basic System II comprises the SR-202 electrostatic headphones and the SRM-212 driver unit. The SR-202, an open-backed electrostatic headphone, is the bottom of Stax’s range. It’s rated frequency range is listed at 7Hz–41kHz, though with no limits quoted. The earpad is “artificial leather”, which I guess means plastic. The weight of the 202 is 440g including cable, or 295g without the cable.

The SRM-212 Driver Unit a small (132x38x132mm) black box. On the back are gold plated input terminals and a power jack for the accompanying wall wart power supply. The front has one “pro” Stax earspeaker output and a volume control. The volume control also doubles as an on-off switch.

The construction of the Basic System II appears adequate rather than awe-inspiring, except in one area where the headphones are let down. The moulded plastic headpiece creaks with the slightest head movement. That may seem trivial, but any noise millimetres from the ear is loud and distracting. It would stop me from buying these phones.

Knock on wood

Hearing into a recording is a major reason for using headphones, and with these Stax phone your can hear why.

I hadn’t listened to the Beatles’ Abbey Road for a while (Rubber Soul and Revolver have held the #1 spot on my Beatles chart lately) so under the phones I went. The different treatments to Ringo’s cymbals are oh so apparent. The beginning of Come Together has Ringo’s cymbals flying free. But towards the end of the track, when Ringo starts riding those cymbals constantly, the limiters are turned to severe, clamping down the sound of his cymbals.

It’s details like these, so easy to hear under the cans, that make headphone listening so interesting. Oregon’s Beyond Words is a fine modern jazz recording. Being able to listen into the recording on this released hybrid SACD is a delight.

Tonally the Stax set is a little lightweight but very airy. Whereas the Perreaux SXH1 combined with my Sennheiser 580s produced a solid and authoritative sound, the Stax lacked that fundamental foundation.

But it made up for it in the airiness and transparency through the upper mids and treble, making the Perreaux/Sennheisser combo sound, in comparison, a little shut in.

Starting all over again

This is a fundamentally fine set of headphones, but not an automatic recommendation. The light tonal balance will tip the Stax out of contention for some, while the creaking of the plastic headpiece will put off others.

However, this is a set of headphones that does sound very good, and should be auditioned by those in the marketplace for an upmarket set of phones. And if you do audition the Stax Basic System II, then make sure you have your credit card with you.