The company name implies a system of viewing, understanding and then treating acoustic phenomena. The founder and present holder of this particular lineage is Franck Tchang, a Parisian guitarist, luthier and goldsmith turned acoustician and speaker designer. It's not too farfetched to speak of lineage as understood in the Martial Arts where a particular school relies on a complex system of katas or movements - especially since Franck is Asian, sympathetic to Buddhist thought and views acoustics as energetic pressure/tension processes. The movements that concern him are those in the air, the final portion of the audio signal path that begins at the source, winds its way electronically to the loudspeaker driver, gets converted to physical push/pull motion by the transducers and creates pressure waves which travel on the air molecules to our ears to be decoded as sounds.

After a few weeks with an assortment of Franck Tchang's resonators, I've come to view them as the most unusual, mind-bending yet efficacious tool I've yet encountered to optimize the audio hardware we so often nearly exclusively focus on as the apparent makers of sound in our homes. The magnitude of improvements is far beyond any of the usual tweak categories and operates in a senior domain.

Because these resonators are small; because they use precious metals; because they aren't cheap; because they apparently defy conventional acoustic theories - the howls of ridicule in the peanut galleries become a predictable response.

The resonators are set up according to a basic formula that starts with three and can get expanded to more than 11. Costs will depend on the metallurgy of the tiny cups. The most expensive one is fabricated from 98% Platinum, the Silver far more affordable.

A tiny trident supports each resonator like a Tibetan singing bowl. Its shaft is embedded in a sliver of hard or soft maple damper which gets attached to the wall via two included dabs of yellow tack. They allow repeat removal without leaving marks. An ongoing review of these devices is already 5 pages long and a concluding one remains to be written. That makes it by far the longest review we've ever published. It's testament to how deserving this subject is. Marja, Henk and Linnman on staff have experimented extensively with the resonators. They now consider them mandatory for their listening rooms. Add me to this resident group now.

Without professing any true or meaningful insights yet into how these resonators go about their business, I'll describe their actions as they appear to me. First off, they act as release valves for pressures that build up inside our dwellings. A small sealed speaker played loud creates very high internal pressure. Add a port and you reduce pressure but introduce ringing, i.e. resonance. The resonators -- somehow -- pierce pressure bubbles that build up especially in the corners. By leveling out overall pressure buildup to equilibrium, the room behaves as though it were far bigger. The audible effects are of course most drastic in the bass. But clean up the low bass and everything gets improved.

Common sensations of room lock and ringing are dissolved, prior SPL ceilings of what the room would support lifted. Further, the resonators can be used to widen and deepen the soundstage, again as though the actual walls of the room were moved or made somehow transparent to the usual giveaway reflections. Because they operate -- again, somehow -- by releasing air pressure differentials, the resonators needn't all be in the room that's apparently being treated. Neither need they be visible. As long as they are surrounded by air which isn't hermetically sealed off from your room, these tiny devices work unimpeded.

There is a very peculiar settling-in period during which internal air pressures go havoc and acoustic damping in the room undergoes bizarre changes, especially if you install a complete advanced set of resonators all at once as I did. These effects are temporary and equalize on their own in a few hours, suggesting that there are dimensions to the resonators' operation beyond what seems apparent.

The effective acoustic damping factor of the room can be tuned by simply moving specific resonators relative especially to the front wall corners. In my case, a placement of 16 inches out from the corners, on the sidewalls, patently overdamped the room. Air and transient incisiveness suffered as though I'd moved heavily stuffed furniture in and perhaps some wall tapestries. Moving the upper and lower corner resonators (Silvers) right into the corners took the literal leash off the transients again. Adding one silver resonator on each side of the front wall in the corner and low to the ground acted like pebbles placed on a picnic blanket to anchor it and keep it spread out. The soundstage rolled into the corners behind and outside the speakers and took up place there as though pinned to the sidewalls. One resonator on each sidewall, exactly half-way between speaker and listening seat, brought the musical energy more into the room to heighten vocal focus and the sense that music was reaching across space from a soundstage apparently residing mostly on the porch (i.e. well behind the speakers).

When I talk about the resonators doing this or that action, I'm merely describing the effects I heard. What they really do -- and how -- is a complete mystery to me. Arm chair critics will point at the presumed high resonant frequencies of the bowls and the long wavelengths of low frequencies and question how they could possibly interact as described. I don't know except to state that, categorically, they do - without the usual cubic yards of fiber glass stuffed into corner traps.

My Zu Audio Definition Pro speakers rely on a professional equalizer for precise in-room linearization of bass. My low pass filter is set to 40Hz to primarily affect the bottom octave. While the EQ allowed me to tailor a very linear, non-lumpy bass response in the listening seat, it didn't at all touch how the concomitant LF pressures -- they always develop especially in the corners behind the speakers -- dampen the high frequencies and overlay the entire audible register with room ringing and resonances.

I managed to electronically notch-filter out boom notes and fill out troughs but the echoes or shadows of that response remained unattended. In other words, no electronic signal manipulation is capable of draining off the compression zones that occur in the corners. Acoustic treatments would, but to be effective at low frequencies, they must be big and voluminous. That means unsightly unless you own your home and can conceal them stealthily in closets or above the ceiling.

If you rent as I do and insist on keeping your listening room looking like a living room, conventional corner traps, abfusors and diffusors are out. Enter the resonators. They install without a nail, they come off without leaving a mark. While they can constitute quite a financial investment if you install two handfuls or more, they'll be a permanent investment that'll work no matter what your next living quarters or speakers happen to be.

Reviewing professionally, I have a reasonable grasp on what can be accomplished through creative hardware substitutions. From a certain point onwards -- let's call it system maturity -- it's all very minor league stuff. Compared to anything I could think of in box world, the resonators are major. What they accomplish is not even
in the same class of improvements. It's well possible of course that if you had an open basement or attic and built out a custom room according to scientific calculations -- dimensions, non-parallel walls, concealed treatments -- the resonators might become superfluous. Or at best, they might reduce in efficacy to not fully warrant their expense. That's pure conjecture on my part but many will find it a plausible hypothesis. What's beyond doubt? Tenants do not have such luxuries. They must work with the rooms they temporarily inherited from their landlords. It is for such "ordinary" audiophiles that the resonators present a truly unique solution.

One question remains for the formal review to answer. How many resonators, minimum, will I need to retain the core benefits of my present over-the-top application - especially now that I know what's possible? How much consolidation might be feasible where certain resonators presently double up a bit to leave only very short-lived memories of loss if they were removed?

For example, the one on the picture frame above my computer monitor (mirrored on the opposing wall as the half-way spot between listening chair and speaker) pulled the gravity of the music farther into the room without relocating the apparent soundstage. The effect was audible but nowhere near as drastic as the doubled-up lower front corner units.

Here's a summary. The resonators make your room behave as though it was far larger. This is particularly noticeable in bass performance -- extension, articulation, clarity -- but also affects air and spatial micro details that otherwise remain stifled by LF pressure zones. The dimensions of the soundstage can be deliberately increased laterally and in the depth domain. Center focus and image density can be improved. The comfort level of high SPL playback goes up because the room no longer protests. Dynamics, large-scale peaks and micro-dynamic fluctuations, get more intense. Because room resonance goes down, recorded decays become stronger and louder. In short, your present system will sound a lot better without upgrading a single component.

In hindsight, I will also say that certain speakers -- my Zu Definitions come to mind, the newer Avantgardes with the revised bass systems -- are, for most realistically sized rooms, really overly ambitious in their bass capabilities. The resonators finally allow you to match your room's ability to that of the speakers. By extension, retailers and trade show exhibitors would be foolish to not consider the Acoustic System resonators for their smaller rooms and on their truly full-range flagship speaker setups that can dish out 20Hz bass.

I leave you with this. Last night, I had one of those "in the zone" sessions we all enjoy at times. I had moved a few resonators and suddenly things just locked. They got enormous but perfectly controlled. The walls, for all intents and purposes, simply vanished. It was dark outside, well past sunset when the older, more primitive part of the brain takes over and the frontal lobes shut down. Would the stupendous sonics of that late-night session transfer into the light of day, with bright sunlight streaming in, mental activities high and an overall psychological mood that was very different from the midnight state? This question didn't occur to me until this morning, naturally. Blame those frontal lobes kicking in. But then they did and I approached the listening room with slight trepidation. I needn't have worried. The magic was just a few power buttons away. The improvements weren't subject to imagination, wishful thinking or some kind of heightened state in the listener. They were objective in the sense of being stable regardless of personal moods or states.

What can I tell you? I haven't been this excited about an audio discovery in a very long time. That's because these resonators are universally applicable. They aren't a matter of personal taste like so many component choices are. While I'm not prepared to say that they do the same as traditional room treatments -- in fact, I very much suspect that they don't -- I will say that I now have no need for traditional room treatments while the resonators are on guard. As tenants and people who view their home as a decorated sanctuary rather than messy office or industrial recording studio, this is unbelievably good and rather unexpected news. For us. I bet it could be for many of our readers as well...
Franck Tchang's e-mail