Potential drawbacks that JansZens don't have
Over the last 35 years or so, a number of other electrostatic speaker companies have put products into production. All demonstrate one and generally at least a few of the drawbacks that JansZen speakers do not have. Here's the list, complete to the best of our knowledge:
dipole operation, meaning equal sound coming out the back as the front, which
requires lots of space
makes best sounding setup tricky to create
causes comb filtering response artifacts
beaming of high frequencies, making the listening area so narrow that one has to sit still right in the middle to get full range sound
lack of membrane resonance damping, which
compromises transient response
invites creation of lateral breakup waves in the membranes
susceptibility to contamination, causing pops and squeals
curved membranes that ultimately saddle back against the rear stator, due to a phenomenon called plastic strain creep, and cause failure
faceted arrangements that cause substantial treble response lobing
susceptibility to self-destruction by arcing
electronic voltage limiting, for avoiding arcing, which
clips off transient peaks
can damage amplifiers
loosening of membranes, requiring service / replacement
destruction of membrane coating over time, requiring service / replacement
when dynamic woofers are present, they are poorly integrated, due to using resonantly boosted deep bass, such as with ported cabinets
lack of bass heft
lack of very high treble
susceptibility to damage during shipment
insufficient loudness overall
lack of slam/impact/percussiveness
So, what does make JansZens better, exactly?
First, here's what's good about all electrostatic speakers (ESLs):
ESL's (Electrostatic Loudspeakers) use nearly weightless membranes for moving the air. It's simple and linear. Also, unlike a cone, dome, or whatever, the force is evenly distributed, so the membrane moves all at once in one direction at a time, without inevitable breakup or differential motion.
You might be familiar with see-though ESL's, but these and most other non-JansZen ESL's are similar to one another, in the sense that the membrane motion is not damped. Our membranes, however, have just the right amount of damping.
Why is that good? As with a shock absorber, all motion is ideally controlled, reacting precisely to the musical signal, never bouncing and bucking along on its own after a sound is supposed to end. This optimizes transient response and eliminates the resonant coloration and break up that affects all undamped planars.
Our ESL's keep the loud transient sounds intact, even at high average loudness, and this contributes to the sense of realism and dynamism. This is possible because our panels are insulated in a way that allows overloads that are three times as high as what will ionize the air in the gaps. Also, the matching transformers can handle these overloads without saturating and putting a low impedance across your amplifier.
This headroom capability also means there's no electronic voltage limiting that could compress the peaks.
As a result, brief, transient overloads, like from drum or piano hammer strikes, will simply be as loud as they are supposed to be, even though the speaker is technically overloaded. You are also free to use amplifiers with significant headroom without worrying about ruining the panels or damaging your amplifiers.
The crossover frequency is 500 Hz, well below the 1 kHz to 3 kHz region where crossover effects can cause audible colorations. We can do this because our ESL's can cover the lower midrange through the treble -- around 350 Hz - 30 kHz. Even more important than avoiding crossover artifacts, all frequencies where accuracy matters most are produced by the most phase-accurate, low distortion, and transient-accurate drivers ever made.
Our ESL's are completely protected from the atmosphere. While high internal voltages draw dust, grease and smoke into other ESL's, an acoustically transparent membrane, only 3 microns thick, protects ours. Any particles that might get through the grill cloth are blocked.
By using fully enclosed cabinets, unlike most planars, JansZens put sound out only to the front. This makes setup as easy as with regular speakers, including the option of placing them against the back wall, It also eliminates the unwanted comb filtering that colors the sound from large area dipoles whose backwave interferes with its own reflection.
JansZen's are all line sources to some extent. They create a wide sweet spot and avoid beaming and exaggerated response lobes without curved membranes or facets. They also have restricted vertical dispersion, minimizing the impact of the room's floor and ceiling on the response, and helping to conserve the recorded ambience.
Our unique Woofer - Midrange/Tweeter - Woofer (WMW) arrangement, similar to D'Appolito's MTM, has a number of advantages:
extends the line effect to lower frequencies
provides time-aligned sound radiation and conserves phase, which sharpens the soundstage image and reduces interference coloration
provides a large woofer area without using a large woofer, which provides better bass transient response.
produces complete vertical image stability, because all frequencies seem to be coming from the same position
reduces floor bounce effects at any particular frequency to half of what they would be
reduces excitation of a room's bass modes.
Gracefully curved scoops are taken out of the front edges of our enclosures to reduce diffraction interference and take whatever is left of it and distribute its frequencies so none is noticeable. This eliminates a source of coloration that affects most speakers.
JansZen's use a sealed woofer enclosure. This cuts group delay to an absolute minimum and produces optimal woofer transient response, both of which are needed to integrate well with ESL's. It also helps control cone motion below resonance, so your amplifier doesn't have to, and this improves performance with tube amplifiers. A ported system may be more efficient, but there is no way it can create accurate bass, and ports allow woofer cones to move past their more linear range and even bottom out on very low notes.
Individually, any of these things is audible. Put them all together, and hearing a pair of JansZen's is like hearing no other speaker, and no other electrostatic -- in fact, it's more like hearing no speaker at all, and that's as close as you can get to being transported into a live musical performance from a stereo recording.
Sign up for articles by David Janszen about audio, plus the latest on new developments, show reports, and more…Original script code: