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The DNA™ Studio™ loudspeaker The DNA Studio loudspeaker is specially created to produce outstanding fidelity similar to our reference Sequence model in a smaller, easier to use, family-friendlier design. Specific goals include: The resulting design is the culmination of 4 years of research, listening, and development, and incorporates many of the key design elements found in the Sequence. Upon first listen you realize that you are experiencing something special. The Studio loudspeaker was recently premiered at Acoustic Image to the LA/OC Audio Society. Comments from listeners include: "I've never heard bass like this before" "The driver integration is seamless" "That was the best I have ever heard Kind of Blue" "These speakers sound better than the $80k Verity Audios (Lohengrin II) we heard the other month" "Yours beat the Magico Mini and V3 tower and a better value too" Description of design The Studio is a 3-way loudspeaker with self-powered dipole woofer. The midbass/tweeter section is 93dB sensitive, achieved by partnering a horn-loaded textile dome tweeter with two 5.75 inch Nomex paper cone midbass drivers in unison. The decision to use two 5.75 inch drivers instead of a single larger driver is due to their superior frequency response and energy-time behavior. From this arose the next design challenge: How to arrange the dual drivers for best sound. To solve it, one must understand the behavior of two spaced sound sources operating together in a reflective environment and human perception. After considerable investigation, the best configuration is lateral placement beside one another centered beneath the tweeter. This arrangement eliminates any audible coloration caused by their off-axis mutual interaction as produced in the common vertical M-T-M arrangement. I will explain how: When a loudspeaker is placed in the room away from side and rear walls as normally done, the first sound reflection from the speaker is the floor reflection. It typically arrives at the listening position only 2ms after the direct sound with little attenuation from the added propagation distance. What this means is the character of the floor reflection is critical. The common vertical M-T-M "D'Appolito"-style configuration produces interference and lobing in the vertical axis caused by the two spaced midbass drivers. Take two identical sound sources, operate them in phase, and look at their polar pattern versus frequency along their axis of separation. You will see interference beginning at frequencies whose wavelengths are twice the separation distance and continuing with increasing frequency. With only two sound sources, the resulting on and off-axis polar lobes have the same sound pressure level; i.e. the mutual interference does not attenuate the amplitude of the off-axis lobes. So for example, a common vertical M-T-M with 6.5 inch midbass drivers has a center-to-center separation distance of 11 inches. With this separation their mutual interference begins at 616 Hz, two octaves below the crossover to the tweeter (typically 2.5 - 3 kHz). Now let's look at the in-room behavior for a vertical M-T-M: Because of the vertical off-axis interference between its spaced midbass drivers, the frequency response of its floor reflection is very uneven with numerous bumps and dips. We encounter and hear floor reflections every day when talking, etc. If one follows the logic that the frequency response of the reflection should be similar to the direct sound (meaning no pronounced peaks and dips), thereby being less noticeable and objectionable, then the vertical M-T-M fails in this regard with its strong and colored floor reflection. Such is an example of a poor design wrought from incomplete knowledge and understanding of the total loudspeaker-listener experience. In contrast, the frequency response of the floor reflection produced by the Studio's midbasses is very uniform because they are equal distance above the floor; there is no mutual interference and their reflection time is identical. In fact, in the vertical plane the dual midbasses with tweeter behave the same as a standard two-way loudspeaker. When assessed in the horizontal plane, the lateral midbasses will exhibit interference with an increased onset frequency of 1130 Hz, due to their close 6 inch center-to-center placement. The midbasses crossover to the tweeter at 2.2 kHz with first order (6dB/oct) filters for a gentle transistion. With the loudspeaker positioned in the room well away from the walls and angled towards to the listener, no side lobe is produced that will directly reflect to the listener. Furthermore, what already attenuated off-axis energy which does reflect from the side wall arrives at the listener delayed and further attenuated due to the greater propagation path length, rendering the side wall reflection audibly inconsequential. The end result of this careful attention is all benefit and no detriment with superior clarity, detail, and tonality which no other dual driver configuration or individual larger transducer can ever match. Continuing about the Studio, the acoustic centers of the tweeter and midbass drivers are vertically aligned to minimize excess phase shift and group delay. First order electrical crossover filters are used between these drivers to further minimize excess phase shift and group delay. These efforts yield 1/3 - 1/10th of the excess group delay as found in competing products. The hand-wired crossover uses components chosen solely by their sound quality. Situated below the midbasses is a custom 12 inch Aurasound woofer operating dipole. Dipole operation energizes the room's standing waves less than sealed and ported alignments and produces the most natural, effortless, and articulate sounding bass. From my experience dipole bass is the only way to accurately reproduce the complex sound of the pipe organ, piano, double bass, cello, and other low-frequency rich instruments in the domestic environment. The woofer is self powered by an internal 180W amplifier which derives its signal from the input binding posts and then performs the necessary dipole equalization. The woofer level is adjustable to allow fine tuning of its balance, depending upon room placement and listening preference. Special input circuitry is utilized to eliminate any hum from potential ground loops, making the Studio compatible and sound its best in any system. There is also the option to run the speakers with an external active crossover for true bi-amplified operation. Last but certainly not least, the Studio's cabinet is specially designed and constructed in California with strategically positioned bracing and damping to yield no audible coloration. The woofer amplifier and midbass-tweeter passive crossover are housed in their own, acoustically isolated chamber. Ultimately the proof is in the sound. Listen for yourself.™ Specifications
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