Ikonoklast 2 DX4

Now, the "magic" of the Ikonoklast triple acoustic length (3/4-wave) transmission line system "sets the Lowther DX-4 driver free to sing its heart out," in a nearly full range system.

The "heart" of the Lowther DX-4 driver is the exclusive rare earth magnet/hi-ferric voice coil system. This innovative feature allows not only ultra-high sensitivity, but also provides superior control of the cone movement, delivering jack hammer-like attacks, deliciously delicate trailouts, and the most natural vocal and instrumental textures "south of $40,000." But effective coupling of the DX-4’s full range output to the listening room is a daunting challenge. Use of sealed, ported or open baffle enclosures can be expected to largely sacrifice the lowest two octaves, likely requiring the use of a slow, high mass subwoofer with a sound-degrading crossover network.

Enter the Ikonoklast2DX4, at only 24 inches high, 11 inches wide and 16 inches deep. Remarkably, our triple length, ¾-wave transmission line bass coupler has been squeezed inside this unassuming shape. By precisely stuffing the entire length of the folded transmission line passageway with the correct density of a specific damping substance, the sound wave is slowed accurately to a fraction of its speed through air. Far from degrading the performance, the stuffing actually smooths the bass response, by lowering the Q of the transmission line’s half wave resonance. The system response is thereby extended deep into the lowest octave, without a narrow response peak. The result is the sort of powerful room-shaking low bass, typically associated with subwoofers, but without their muddy loudspeaker-like sound.

But the powerful low bass of the Ikonolast2DX4 is much clearer and more defined, because the ¾-wave acoustic transmission line length has been aligned to precisely control the driver’s main resonance, eliminating the loudspeaker-like quality of a typical woofer or subwoofer, and allowing reproduction of the most subtle bass textures and nuances that seldom are heard except in unamplified, live music.

Although awesomely clear low bass is a key distinguishing characteristic of this system, most of the music is in the midrange, and this enclosure has an important design feature that allows the DX-4 driver to shine in the midrange, very much like an open baffle system. Instead of the rear wave from the cone being reflected from the flat back of the cabinet, the cylindrical shape of the internal terminating section of the transmission line reflects midrange energy in multiple directions. This prevents midrange standing waves from propagating inside the cabinet and being re-radiated through the cone. The listening effect is an almost total absence of any ,boxy quality of the reproduced midrange.

Because the DX-4 driver has excellent high frequency response, with wide dispersion, no tweeter is required for thrilling, virtually full range reproduction.

Ikonoklast 2 DX4 Specifications

  • Single Driver System: using Lowther DX-4
  • Enclosure: Acoustically Full Size ¾-Wave Transmission Line
  • No crossover network
  • Sensitivity: 100dB+
  • Frequency Response: 30Hz to 20kHz (-3dB @37Hz)
  • Input Connectors: Banana Jack/Binding Posts, Silver Plated Brass
  • Amplifier Power Requirements: 1 to 100 Watts. (Tube SET preferred)
  • Size: 24"H X 11"W X 16"D
  • Stands Included: Height 18.5 Inches
  • Finish: Front/back/sides- Natural Oiled Mahogany Veneer
  • Top: High Gloss Acrylic

Technical Information

IKonoklast 2 DX4 Price: $6500 per pair
(Includes custom black stained Mahogany sand fillable bases)

Ikonoklast 3 HO

With New High Output Tweeter

"Everyone knows that a fine speaker's crossover network should be copiously configured with abundant capacitors, inductors and resistors." But we have eliminated the entire crossover network - not even a single component remains to degrade, distort and compress. Our piezoelectric tweeter motor is engineered with an "automatic" low frequency roll-off. The mid/LF driver is likewise designed with a complementary high end roll-off.

"Famous speaker designers agree that a massive woofer with a low resonance frequency is required to reproduce the lowest bass notes." But also, we have eliminated the woofer - instead, we coax powerful and palpable deep bass from our ultra low-mass midrange driver, by back-loading it into a "triple length" (3/4-wave) acoustic transmission line enclosure.

"Common knowledge dictates: small, wide band, linear systems require behemoth amplifiers." 5 Watts, anyone? With 5 to 70 Watts suggested, the IKONOKLAST3 even delights with lower power. Its incisiveness at extremely low listening volumes is facilitated by the "crossover-less" direct connection to the amplifier. Now hear all the music at very low listening levels, or this system can “raise the roof’ when required.

Dual Coherent Line Array High Output Tweeter

A cornerstone of this revolutionary system design is our exclusive, Walsh-type coherent line, 360-degree dispersion, bending wave tweeter. Our all new implementation of this superlative concept has reduced its moving mass to only about 1/25th that of the finest moving coil dome tweeters. We believe that nothing like our dual "stacked ice-cream cone" design with ultra low-mass piezoelectric motor has ever before been offered, commercially. This fast, open and remarkably "un-tizzy" sounding reproducer extends system response beyond the ordinary to almost 50kHz, indicating unexcelled transient ability. Since January 2008, all Ikonoklast dual tweeters have been equipped with a new more powerful motor system. This new technology allows the tweeter to dominate Ikonoklast3's midrange output. The overall quality of reporduction is greatly improved and the system now will play much louder. MICRO-MASS MID/LF DRIVER

Our mid/LF driver (Please don't call it a woofer!) has been manufactured to the highest standards in one of Europe's premier facilities. An edge-wound flat copper voice coil on kapton former and non-resonant die cast chassis exemplify its state-of-the-art construction. The membrane, crafted of a critically aligned mix of carbon and kevlar fibers, embedded in an acrylic polymer gel, may offer the ultimate in near-perfect piston behavior. Total moving mass is about 7 grams! With its main resonance neutralized in steadfast equilibrium, and negligible back-pressure by the acoustic delay line, unveiled is "a mid range to die for." Moreover, our extra long (3/4-wave) transmission line enables its nimble quickness to foray confidently into the depths of the two lowest octaves, with uncompromising authority.


Seasoned transmission line designers concur on an acoustical length of about 1/4-wavelength, at the free air resonance frequency of the driver (Fs). This traditional alignment provides response to slightly below the resonance frequency, with effective selective damping of Fs, and broad reinforcement of the output above the main resonance, at Fs x 2 (the line's 1/2-wave resonance). But our new 3/4-wave alignment provides equivalent selective damping of Fs, while instead, reinforcing a broad band of frequencies below Fs. Since this broad 1/2-wave resonance of IKONOKLAST3's transmission line centers on 45Hz, response of the low mass, high resonance driver is extended usefully to below 30Hz.


Even though its mid/LF driver is only 5-1/4 inches diameter, IKONOKLAST3 does not present like a "mini-monitor," - It has dramatically wider dynamic range and deep low-end "extension." Better yet, the bass does not suffer from time domain overshoot, as in typical good sealed or ported systems. This can cause unaccustomed listeners, at first, to think the bass may be lacking.- But when genuine, strong, detailed low bass is played, the "dancing, prancing," extra long transmission line bass system robustly reveals separate bass notes- slurred on other speakers, plus "deliciously nuanced" micro-textures - all with ardor and dash.


The two drivers' acoustic centers are aligned in the forward/rearward plane to provide simultaneous arrival times. Although this technique has been used in numerous good speaker systems, the net effect is greatly enhanced here, now that time/phase distortions introduced by crossover network components have been completely eliminated. The result is coherent sonic imaging not previously associated with systems in this size, price and sensitivity class. Because of the 360-degree horizontal dispersion of the tweeter, the enhanced stereo image can be enjoyed over a wide area, about three times greater than other systems. Further, we believe that monaural reproduction on only one IKONOKLAST3 sounds broader, deeper, and more satisfying than stereo on many conventional systems. And the "crossover-less," time/phase alignment of the drivers delivers more than just a stunning stereo image: the nearly perfect coherence of the wide band sound front imparts to instruments and voices much of that elusive, "full, rounded" character of original live events.


  • Frequency Response: 30Hz to 50kHz
  • Sensitivity: 95dB/2.83V/m
  • Nominal Impedance : 8 Ohms
  • Power Handling (Long/Short term) : 50/70W
  • Cabinet Dimensions:24"H x 8-1/4"W x 12"D (Note: Tweeter extends 10 inches above cabinet top.)
  • Cabinet Finish: Oiled Mahogany Veneer

(Link to IK technical info)... need link

Ikonoklast 3 HO Price: $4000 per pair

Ikonoklast 5A

The same mid/LF reproducer used in the konoklast 3 HO system is paired here with the single membrane piezo Walsh tweeter to produce a price to performance ratio heretofore unattainable. The underlying key to the superlative sonic realism is provision of our exclusive 3/4-wave transmission line enclosure for the Mid/LF driver.

This advanced technology back loading system does what many loudspeaker designers would consider impossible: it enables a light weight moving system midrange drive unit (only7 grams mms) to operate all the way down, to below 30Hz with unbelievable power, for its diminutive 5.25" size. The system provides un-rolled-off, flat response to near 40Hz, in a typical small room!

But, extended low frequency response is only part of the triple length transmission line advantage.

Use of the same driver to reproduce the midrange and low bass is significant in that it eliminates the need for a phase distorting, stereo image degrading, reactive crossover network, containing sound quality obliterating capacitors and inductors.

The "zero crossover components" theme is carried even to the transition between the Mid/LF driver and the Coherent Line Source tweeter. The Tweeter's unconventional piezoelectric motor automatically rejects lower frequencies, while the Mid/LF driver exhibits a complementary, automatic high frequency rolloff. The output of the two drivers is thereby effortlessly blended, using the absolute optimum number of capacitive and inductive crossover network components: zero.

Combined with physical arrival time compensation mounting of the tweeter and Mid/LF reproducer, the crossover-less transition regenerates a coherent sound front that keeps both drivers in nearly perfect phase relationship in the crossover region and beyond. The result is a more stable and convincing stereo image and an engaging "roundness" to the sound of reproduced voices and instruments.

When sensitive low mass drive units are directly connected to the driving amplifier, without intervening power robbing crossover components, good things happen to sensitivity. This effect is enhanced by the low back pressure transmission line loading for the Mid/LF element, freeing it from the necessity to struggle against the cushion of trapped air that characterizes the more typical sealed or ported enclosures.

The average room sensitivity of 92dB indicates the system should be easy to drive, but it doesn't tell the whole story.

Ikonoklast 5A sounds clear and engaging when reproducing lower sound pressure levels than other systems with similar numeric sensitivity ratings. We refer to this concept as downward dynamic range. It is partly this quality that enables the system to be driven satisfyingly, even with micro-powered amplifiers.

Ikonoklast 5A is available finished in warm rich oiled Mahogany veneer.

Ikonoklast 5A price: $3000

Ikonoklast Tweeters

Now Available as separate Drivers

Since the introduction of our Ikonoklast speaker systems, we have received numerous requests from people who build their own speaker systems, and who wish to purchase our superlative Walsh type tweeters for use in systems of their own design and construction.

We have responded by making the tweeters available for separate purchase, as follows:

  • Integrates with drivers of 93-96dB sesitivity*
  • Frequency range 2-40kHz
  • Vertical dispersion pattern 30 degrees
  • Integrates with drivers of 89-92dB sensitivity*
  • Frequency range 2-40kHz
  • Vertical dispersion pattern 15 degrees

*Resistive attenuation may be used to integrate with less sensitive mid/lf frequency drive units.


The tweeters are supplied with pure 5N silver input leads and the same flexible disk, snap-on mounting hardware used on our complete systems.

In addition, we have prepared an extensive information package to assist the designer/builder with integrating the driver into a complete system. This includes a description of a process for aligning the acoustical centers of the drivers with each other (front to rear), for minimum phase difference, without the use of costly specialized test instruments.

The tweeters may be returned to us for a 50% refund within 30 days after being received by the buyer. Cost to repair any damage to the units by the customer shall also be deducted from any refund. We regret that we must charge this relatively high "restocking fee" but, otherwise we feel we would likely receive an unduly large number of orders from persons who have no intention of keeping the product. The information package we supply may be retained by the buyer, even if the tweeters are returned for the specified 50% refund.

Federal Express, USA shipping for one pair of tweeters is $23.00. For international orders, please call 510-633-9353, or fax 510-597-0421 for quote.


Ikonoklast 3HO Review

Original Ikonoklast 3 and 5 Review

Technical Information