Presenting the DNA™ Sequence™ speakers, where form follows physics™.

The DNA Sequence loudspeakers are specially created with one goal: Produce the best possible sound in-room at the listening postion.

How is this goal accomplished?

• Use the highest quality components chosen by their performance: woofers, midranges, tweeters, crossover elements, etc.
• Minimize the room's influence on the sound heard at the listening position
• Be compatible with the highest fidelity amplifiers: Single Ended Triodes

The resulting design is the culmination of 12 years of listening, research, and development.

Comments from listeners include:

"This might be the best midrange I've ever heard. They remind me of original Quads." Elliot Midwood, Acoustic Image

"These have the speed and attack like an electrostatic loudspeaker. How are you doing it?" Rainier Israel, Hi-Fi distributor in Germany

"They possess the clarity of studio master tapes." Geoffrey Dillon, audio guru

"You should be proud. I hope you do well." Andrew Kotsatos, founder of Boston Acoustics

"Filed under the weird and wonderful were the Nordic Concept Turntable from Sweden and Sequence speakers from Donald North Audio. Another charmer, North explained his Sequence speaker design carefully and the design behind the fascinating Nordic turntable. The sound in this room was very musical - with an intriguing look to match." Anthony Kershaw of Audiophilia reporting on CES 2003

Here's why:

The theoretical goal of a loudspeaker system is to reproduce the sound field as when it was originally made. To properly design a loudspeaker, it must first be understood how sound fields are recorded and the environment in which the playback will typically occur.

When sounds are created, the sound waves (energy) are radiated in all directions. This total energy can be considered a sound field. A person listening to the original acoustical event is of small size in relation to the size of the total sound field and could be considered as a point in the sound field. Likewise, when sounds are recorded, they are captured with a microphone, which is also of small size in relation to the sound field and would also be considered as a point in the sound field.

When reproducing such sounds, the optimum playback mechanism is through an acoustical point source. A point source is a theoretical, infinitely small sound source capable of reproducing all frequencies from the same physical location. Once example of a point source is a single transducer. Unfortunately, no single transducer can reproduce sounds uniformly at typical listening levels over the entire audio frequency spectrum with minimal distortion or coloration.

To overcome some of the limitations of single transducer systems, most loudspeakers use multiple transducers of different sizes to reproduce the full range of the audible frequency spectrum. The most common approach is to use a small transducer optimized for high frequency reproduction (tweeters) mounted near the top of the enclosure at ear level and one or more larger transducers optimized for low frequency reproduction (woofers) below the tweeter. With this approach, however, the speaker system no longer emulates a point source, and the human ear is sensitive to the direction of sound and can notice the different physical locations of these transducers. To compound the problem this traditional arrangement also yields different path lengths from each transducer to the listener so that the respective sounds do not arrive all at the same time. The resultant reproduced sound field does not sound like the original source.

Hi-fi loudspeakers are typically used indoors. When they reproduce sound, the generated sound waves travel in all directions. Ideally, the listener should hear only the sound waves traveling towards him/her. In actuality the listener hears these direct sound waves and those reflected waves which bounce off the room's surfaces, primarily the walls, floor, and ceiling. Since these reflected sound waves have traveled a longer distance to the listener than the direct waves, they are delayed in relation to the direct sound. The waveform heard by the listener is incorrect, being distorted by the combination of the direct and reflected sound. Thus, the listener is not hearing the sound field as it was originally generated or recorded and, instead, is hearing a severely distorted sound field that bears little resemblance to the original event.

At lower frequencies, typically from 200 Hz and below, these reflections form into acoustic standing waves within rooms, based on the size and geometry of the room. Conventional closed box and ported box loudspeakers at these lower frequencies are essentially omnidirectional, radiating sound equally in all directions, much like a point source. This omnidirectional sound radiation easily interacts with and excites these standing wave room modes, resulting in an uneven, unnatural bass response.

The DNA™ Sequence™ loudspeaker solves these problems by maximizing the sound directed towards the listener while minimizing sound being directed towards first-reflective surfaces (floor, side walls, ceiling) and into standing wave room modes. This is accomplished through the clever use of a proprietary time-aligned, directional, point-source, high efficiency, quad midrange - tweeter satellite array and dipole woofer. I know of no other commercial speaker which can make all these claims.

When the speakers are properly positioned, they are angled directly to the listening position. When seated, your ears are at the same height as the tweeter and the center of the midrange array. The sound path length to the ears is identical for all 4 midranges, so they arrive at your ears at the same time. However in relation to the floor, side walls, and ceiling, the midrange array is 4 unique distances away and causes destructive interference, thereby reducing the sound levels of the primary reflections.

While other companies spend thousands of dollars on advertising to lure and dupe prospective customers touting dubious innovations like aspherical group delay or flaunting some Japanese audio Grand Prix award, they fail to address the basic yet essential goal of reproducing a flat frequency response in-room at the listening position. This makes one wonder, exactly what fundamental improvements in sound reproduction have they accomplished, particularly among those manufacturers who allegedly have been refining (more like rehashing) the same design over and over again with one version after the next? With the DNA Sequence speakers their patented innovation is immediately apparent by the uniqueness of their design and witnessed sound quality.

Features of the DNA Sequence™ loudspeakers include:

• High efficiency 95 dB/ 8 ohms satellite array can be used with practically any amplifier: You choose the amplifier based on its sonic merits and not power output. Perfect for use with low wattage triode tube amplifiers.
  
• Quad midrange satellite in proprietary (US patent 6,801,631) controlled-directivity point source configuration to minimize first reflections (floor, side walls, ceilling) for superior vocal and instrument clarity, image placement, and overall soundstaging.
  
• Half of the music spectrum (5 octaves) reproduced through the quad midrange array for unmatched tonal coherence - no crossovers in the critical midrange where the ear is most sensitive.
  
• Speed and clarity with low energy storage rivaling that of electrostatic speakers.
  
• Midrange array intentionally used in sealed enclosure for precise, focused imaging - more true to the recording than dipole midranges which sound diffuse in comparison.
  
• Directional dipole (open baffle) woofer for the most effortless, natural sounding bass with minimal room interaction and standing wave excitation.
  
• Transducers very carefully selected for best sound quality:
  1 - 1 inch modified textile dome tweeter with acoustic horn loading made in Denmark
  4 - 5.75 inch polypropylene sandwich cone midranges made in Denmark - possibly the best midrange driver ever made!
  1 - 15.5 inch custom AuraSound long-throw, aluminum cone woofer
  
  
• 15.5 inch woofer has over 1 inch peak-peak linear excursion for low distortion.
  Critical midrange frequencies divided among 4 midrange drivers produces very low excursion in each driver yielding very low harmonic and IM distortion.
  
• 15.5 inch woofer features 4 inch diameter voice coil in underhung configuration for high power handling and low thermal compression.
  Critical midrange frequencies divided among 4 midrange drivers resulting in low thermal compression for lifelike dynamics.

• Time aligned quad midrange - tweeter array with first-order electrical crossover slopes for minimal phase shift and time delay.
  
• 3-way design with an active crossover between woofer and midranges and a passive crossover between midranges and tweeter.
  
• Minimalist 7-element passive midrange-tweeter crossover uses components selected for best sound quality, regardless of price.
  
• For the tube "die-hard", a 10 tube (4 6SN7s and 6 6C45s), single-ended class A, zero-feedback, all triode active crossover is employed. Satellite highpass section is ultra quiet with very wide bandwidth. Uses over 400 parts including Audio Note copper foil capacitors. Note the double decker power supply! Black acrylic faceplate is custom laser engraved. Designed by legendary circuit genius Brad Wood. Includes bass level control for gain matching of different amplifiers.
  
• Cabinetry handmade in California by the same craftsmen whose skilled hands made those on the renown Infinity IRS V.
  
• Specially braced and damped satellite cabinet for no audible coloration.

 

Specifications:

• Frequency response: +/- 3dB from 30 Hz - 18 kHz in room at the listening position, measured without spatial averaging or other tricks
  
• Radiation pattern:
  Dipole bass
  Cardioid midbass
  Directional point source midrange & treble
  
• Sensitivity: 95dB/2.83V/1m for satellite section
  
• Impedance:
  Satellite array: 8 ohm
  Dipole woofer: 8 ohm
  
• Imaging Index of 9 dB in-room at listening postion
  
• Recommended minimum amplifer power:
  Satellite array: 3 watts per channel into 8 ohms
  Dipole woofer: 100 watts per channel into 8 ohms
  
• Dimensions: 45" H x 18.5" W x 13" D (at base)
  
• Standard finishes: Natural cherry (as pictured) or high gloss white. Custom finishes available.
  
  
  DNA Sequence loudspeakers are proudly made in the United States of America from the finest components available.
  

U.S. Retail price: $20,000 system with triode active crossover

 

DNA Sequence loudspeakers are sold factory direct in North America.
Contact us for a demonstration
Tel: 1 310 869 6214
E-mail DNA

Also on display in Stockholm, Sweden:
AudioConcept
Södra Agnegatan 29
112 29 Stockholm
Tel: +46 (0)8 650 72 50
info@audioconcept.se

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