Teresonic Loudspeakers Technology

Teresonic loudspeakers are uniquely designed, and they are made like fine musical instruments that they replicate the sound of. They inspired John Atkinson, the editor of Stereophile to report "…astonishing sensitivity … LF extension… superb dynamics and clarity…"

Musical Instrument-like

With Teresonic speakers there is nothing that stands between you and your music. Everything about Teresonic speakers is focused on improving your listening experience – from performance, to musicality and timeless value.

Musical instruments are not built as square shaped boxes for a reason! Conventional box speakers sound like box speakers! Ours don't.

"Have you ever wondered why there are no square shape violins, trumpets, or acoustic guitars… so, why do they make square speakers? Because it's very hard to make them like we do," said Mike Zivkovic, President of Teresonic. "Teresonic loudspeakers are designed following centuries old, proven techniques used in designing and making fine musical instruments, combined with latest science, materials and technology."

Teresonic speakers are designed and built like musical instruments (think violin, cello…) – to sound like musical instruments! Form follows function and Teresonic enclosures tend to be very attractive, sculpture-like shapes – like fine music instruments. Timeless beauty and elegance makes Teresonic speakers welcome in every home.

Regardless of the way you consider them- a piece of art that sounds great or as great sounding speakers in an eye pleasing package, all Teresonic speakers are built entirely by hand to the highest standards, using the finest materials and components available. High gloss finish, applied in layer upon layer, enhances the natural wood veneer and superb craftsmanship to create an acoustic instrument for generations.

Extreme Loudspeaker Sensitivity

Own a SET amplifier? SET and speaker matching is critical, as SETs need highly efficient (min 95db) speakers and simple crossovers to begin working their magic. Don't get it wrong, SET can sound good with 88db, but the real magic begins at 95db. Teresonic goes a step further: 98-103dB efficiency and no crossover! Let the magic begin.

Teresonic speakers will give you the best out of your solid state amplifier too. Just keep in mind that solid state amplifiers are not all made equal. The "quality over power" rule should always be applied.
Teresonic provides for extraordinary levels of performance through their high efficiency speakers – from 98dB to 103dB, compared to less than 90 dB efficiency of most speakers – that's over 10 dB of difference - or more than ten times! This level of efficiency and sound quality is not found in traditional multi-driver speakers, except in some products costing over $50,000.


Teresonic speakers are deliberately designed to take full advantage of low power amplifiers, and that is what they do best. Never mind the fact that you just do not need more than about 50 wpc to play music as loudly as you would ever want to (if 1 watt is good for 98 db, then 32 watts are good for a peak output of about 113 db at one meter distance). More importantly, higher power usually leads to a decrease in sound quality or exponentially higher price! From an engineering point of view, it's clearly easier and less expensive to design and manufacture a high-quality 10W amplifier than an equal quality 100W or 500W monster.

Single-driver, Crossover-less Design

Music is made up of approximately 70% midrange. If the midrange is not right, then the remainder of the frequency spectrum does not matter. Conventional speaker designs put a crossover in the mid-range (usually around 400 Hz and 3,000 Hz) to split the signal to the midrange unit, the bass driver, and the tweeter. This is exactly the region where our hearing is most sensitive. Some people consider crossover networks one of the most evil things in audio, introducing sound coloration, phase distortions, and signal losses. Hence deterioration in detail, transparency and imaging. Even worse, most speakers go from a cone driver for the bass to a tweeter with totally different sonic characteristics, such as a dome or ribbon tweeter, for the treble.
Every sound source in nature is radiating sound waves from a single "point" – whether it's a violin, a trumpet, or a human voice. Teresonic speakers follow this design rule of Nature with a one-way design, using full-range, high-efficiency drivers – translating the model of a theoretically perfect singular acoustic source to create an absolutely natural sonic performance.

The single-driver (one-way), straight-through design with no crossover enables highly natural sonic character that really makes music, music. Full-range drivers cover the entire audible frequency spectrum using only one driver unit, thus entirely eliminating the need for an electronic crossover network! The quality of the drive unit and elimination of crossover pays big dividends, with sky-high levels of detail, wide-ranging dynamics and coherence. Just as important is the rock-solid imaging that precisely places instruments in the soundstage – and it keeps them in place!

The ability of the Teresonic single driver speakers to speak across the full frequency spectrum with one voice, and with such speed and lack of coloration, makes them seem all the more electrostatic. In the end, however, the Teresonic speakers will play much louder than all except the largest ESLs, and they will best any ESL in bass power and dynamic wallop. You can hit these speakers with hard transients and they not only do not flinch, they start and stop on a dime and deliver the full frequency and dynamic range of the signal. The Teresonic speakers pass on the sonic thumbprints of the rest of the components in the system rather than changing it. We believe that the loudspeakers shell not hide or alter any aspect of the signal they are fed.

Phase Accuracy and Coherence

Our hearing is quite sensitive to phase accuracy. It is often discussed in conjunction with coherence in reproduction of musical instruments and vocals.

The fundamental problem created by lack of phase accuracy in multiple driver loudspeakers causes different types of insoluble problems. This leads to lost and corrupted harmonics, lost spatial and localization information, and lost micro-dynamics. Phase accurate speakers, such as the high efficiency speakers provided by Teresonic, are simply more musical, dynamic, and transparent – providing more realistic listening experience.

Teresonic single driver speakers design preserves full phase accuracy to assure perfect coherency of instruments and vocals. Loudspeakers with multiple drivers emit individual wave fronts which are mostly out-of-phase with each other. They also require that the listener sits in a specified position, often called "sweet spot", with respect to the speaker placement. Additionally, crossovers introduce phase anomalies which prevent true and accurate coherence, whether or not the listener is in the best listening position. Read more about phase distortions…

When you experience a speaker without phase accuracy problems, you'll quickly understand how sensitive we are to timing information. Here are some effects of phase distortions:

  • beginnings and endings of notes becomes obscured.: voices lisp, strings irritate, basses become 'boxy'…
  • instruments and voices move around in space -- a shifting soundstage
  • small things that help us to define reality become obscured as our brain responds to precise timing between fingers on the piano keys…
  • events get smeared in time and it is echoes which start appearing first so it becomes difficult to 'see' the location of the artist
  • timbre of instruments change -- the unique voice or texture of an instrument is lost

Full Frequency Range

ETQWT© (Enhanced Tapered Quarter Wave Tube) transmission line technology is the key to Teresonic speakers' extremely clean and accurate midrange, the widest range of sound audible to our ears, and extended low frequency response.

Lowther drivers are known for their clarity, exceptional micro and macro dynamics, speed and pace'n'rhythm. On the other hand, they depend on the loudspeaker designer to assure a full frequency response, especially at the low end. Teresonic ETQWT technology solves this challenge with an acoustically active loudspeaker design.The purpose of the speaker enclosure is to bring out the best of the drive-units. Teresonic enclosures go a step further – they enhance the capabilities of the driver by extending the low end up to one-half octave below the fundamental resonant frequency of the driver.

Not only is the low frequency range of Teresonic speakers unmatched by other single-driver (one-way) designs, its bass response is fast and clean. Another benefit of this fast and 'tight' bass is that it doesn't create listening fatigue. Fast and clean bass reproduction is also critical to avoid "mudding" the midrange. This happens in many multi-driver systems with large diameter bass drivers that are just slower than midrange driver .

Teresonic loudspeaker enclosures are "acoustically active" – just like violins, cellos, acoustic bass and other musical instruments. In contrast, traditional speaker designs are "acoustically dead" inside the cabinet in order to avoid resonances, standing waves and other acoustic problems. By our choices of shape, avoidance of parallel surfaces, construction and materials, we minimize internal resonances, negative diffraction effects and cabinet vibrations in order to produce acoustic instruments for generations.

Helmholtz resonators

Teresonic pioneered use of Helmholtz resonators – acoustically active elements, in loudspeaker design. They are designed to "pick out" particular frequencies from a complex sound. They 'iron out' undesired "peaks and valleys" in the frequency spectrum produced by the drivers. Purely acoustical, rather than electronic elements, they are responsible for the exceptionally smooth response of Teresonic speakers without distortions and unwanted colorations.

The research of Herman L. F. von Helmholtz (1821-1894) straddled the interfaces between physics, physiology and psychology. His book, On the Sensations of Tone, published in 1862, at first appears to be on music and its perception, but on a deeper examination, is also a classic textbook on the subject of vibrations. The book describes the form of a resonator that he developed for picking out particular frequencies from a complex sound.

A Helmholtz resonator is a container of air with an open hole (or neck, or port). A volume of air in and near the open hole vibrates because of the 'springiness' of the air inside. A common example is an empty bottle: the air inside vibrates when you blow across the top. (It's a fun experiment, because of the surprisingly low and loud sound that results.) Loudspeaker enclosures use the Helmholtz resonance of the enclosure to smooth out the speaker response across the full range and to boost the low frequency response. 

Read more about Helmholtz resonators >>>

Lowther drivers

Lowther drivers, used in Teresonic speakers exclusively, are hand-made by Lowther-Voigt Ltd in England. All Lowther drivers incorporate extremely powerful magnets and ultra-light paper cones, leading to extraordinary sensitivity, transient response, and low distortion.

After more than 70 years in business, Lowther has been improving and refining their products to be the best full range drivers available. Lowther strives to make full-range drivers that are natural-sounding, with very low coloration. In truth, the majority of Lowther designs do manifest a degree of coloration that we (and many others) find unacceptable. This is primarily due to some of the driver's peculiarities that, if not treated properly, tend to produce "shouty", overly-forward and colored presentation. If the speaker designer overcomes this challenge, the rewards are plentiful and abundant.

After more than 20 years of research and experimentation, Teresonic engineers created loudspeakers using acoustically active enclosures, ETQWT technology, and Helmholtz resonators in order to overcome the Lowther driver's issues and to take full advantage of their strengths. These all reflect the Lowther design philosophy:

  • One Voice Coil per driver obviating problems caused by crossovers, assuring accurate time and phase alignment
  • The special rolled (not formed) paper is extremely thin and light weight
  • The design is implemented as a 3-way: a) the radiation from the Voice Coil edge radiates directly into the annulus between the phase plug and the whizzer cone, b) the whizzer cone handles the wide midrange, and c) the main cone handles the bass. The "crossover" is via mechanical decoupling between the radiating elements.
  • The Voice Coils are wound with materials such as pure silver, copper or aluminum
  • As high efficiency speakers, they all play around 100 dB in an actual listening room with as little as 1 watt of power
  • Lowther magnetic circuits are unique in the market. The size, weight, and flux density of the magnets are enormous for the size of cone

Aficionados say "Lowther for Life". They mean that once Lowther loudspeakers are heard, audio and hi-fi perfectionists stay with them for life. And those that stray come back.

Read more about Lowther >>>


Teresonic speakers are built using the world's very best components, such as the Teresonic made zero interference Clarison cables, and WBT terminals and silver soldering.  
Many high-end speakers on the market will use standard wiring inside the box between drivers and connectors inside the box. Not so with Teresonic speakers, which are equipped with same Clarison high-end audio cables inside the box as those that are used to connect to your amplifier. These cables are fully magnetically shielded to protect the music signal inside the box, where magnetic fields are exceptionally strong. Lowther drivers are equipped with some of the strongest drivers, with a magnetic flux of up to 2.2 Tesla (22,000 Gauss) so protecting the music signal inside the enclosure is critical.

Matching speaker cables and wiring inside the enclosure is also important to maintain the sonic character in the entire chain. Therefore, we recommend using Teresonic speaker cables outside the enclosure.

Notice that matching WBT terminals are used on both speakers and speaker cables assuring a perfect contact is achieved.

WBT is universally regarded as the manufacturer of the world's finest audio connectors. A binding post from WBT is a symbol of quality. A single pole terminal is able to handle a 200A continuous current, and has a patented clamping mechanism for high compression connection of spade connectors and crimped wire. The post accepts a 4mm banana plug, 6mm or 8mm spades and features a patented rotating collar design that requires only finger tightening to securely fasten a spade.

The WBT approach is to develop innovative designs and to build them with the finest materials. Oxygen Free Copper Alloy, Teflon™, and 24K gold are employed to produce connectors like none other. This cost-no-object connector features the most powerful locking mechanism in the business and is precision machined in Germany to exacting tolerances of < 2/100 mm. The base metal is an extremely conductive, proprietary alloy based on over 99.996% pure copper.

By rigidly coupling a loudspeaker enclosure to a floor by means of a "spiking" system, it is possible to significantly improve clarity, stereo imaging and bass response. Speakers produce sound by moving a paper-cone back and forth, thus pushing on the air in the room. Air, due to inertia, tries to resist motion. So, the speaker ends up exerting force against its own cabinet instead. This causes the cabinet to move. If you can prevent the cabinet from moving, more of the energy is used to move the air, rather than the cabinet. The easiest way to keep your speaker cabinet from moving is to place it on a hard surface. If you place it on a soft surface like carpet, it can move too easily. Installing spikes on the bottom of your speaker cabinet allows it to essentially reach through the carpet (and padding) and onto the hard floor below. 

Teresonic speakers come with spikes that serve a dual function. Spike focuses all of the weight of the speaker onto a single point. If the base of the speaker measures 10" x 10" (100 square inches of surface area) and weighs 100 lbs., that equals 1 pound per square inch exerted onto the floor. Now, by placing your speaker on cones you can reduce the surface area to a tiny point that may exert thousands of pounds per square inch onto the floor. That prevents the loudspeaker from moving. In addition, the cones allow mechanical energy from the speaker to be absorbed by the floor, but will not allow energy in the floor to reach the speaker.

These attractive spikes are precision machined from solid brass and then plated with a durable gold finish. The cones are super-high quality and are polished to a mirror-like finish. They look and feel like fine jewelry. Each cone spike weighs 86 grams and measures 1-1/4" diameter and 1-1/2" tall. The two piece threaded tip design allows for precise level adjustment. Floor protecting disks are also included.

Teresonic speakers are possessed of a stunning sense of aliveness and vitality, and have a degree of sonic invisibility that is both seductive and addictive. They play to high volumes quite easily with miniscule amplifiers of as little as 1-10 wpc, but they can take up to 100 wpc. When properly placed in a room (they like to be in the vicinity of a corner but not shoved all of the way into one), they produce very even, phase-correct response from the lower 30s all of the way up to well over 18 kHz, where our hearing begins to taper off. One can describe the sound as like electrostatic speakers in many respects, as the speakers' response to a signal is almost instantaneous due to the extremely low moving mass of the Lowther drivers.