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2001
Sensitivity (2.83v@ 1 meter) 86 dB
Impedance 8 Ohm
Frequency Response 30 Hz-30kHz
Crossover Frequency 2.5 Hz
Recommended
Amplifier Power (Watt) 50-300
Dimensions (HxWxD) 325x140x330mm
Net weight (Per speaker) 21 Kg
THE STANDS ARE EXTRA !
The 2000 series loudspeakers are compact high performance systems matched to the finest audio components. Every single component was chosen carefully to enhance the sonic purity. The goal was to make a family of speakers that could convey every musical nuance beyond what is currently considered state of the art in small monitors.
The 2000 Tweeter
At the heart of this transducer is a pure aluminum diaphragm , perfectly formed into a one-piece dome and voice-coil former. The coil is wound onto the diaphragm itself with exacting precision. This eliminates a critical bond between the coil and dome usually found in typical dome drivers. The advantage apart from improved transient ability and smoother, consistent frequency response is the additional benefit of reduced voice-coil operating temperature as head generated in the coil is able to radiate out from the dome itself. Lower coil temperatures greatly benefit dynamic linearity in transducer systems resulting in more faithful performance of the music.
The high flux, shielded magnet system provides a linear magnet field to the voice-coil which is immersed in a low viscosity magnetic liquid which is suspended in the magnet gap. This fluid allows the efficient thermal transfer of heat generated in the coil to the surrounding structure. The addition of this fluid gives almost 10 times greater power handling on peak input. This tweeter is able to withstand short term transients in excess of 5,000 watts.
The diaphragm is loaded into a short exponential horn with a low compression ratio so distortion is extremely low. PA horns tend to have a high compression ratio which is needed to achieve higher efficiencies at the sacrifice of increased "throat distortion" caused by saturation of the air-load in the throat (or entrance) of the horn. The length of the horn coincides with the acoustic center of the 150mm woofer. That is that both the woofer and tweeter voice coil are in the same vertical plane so that there is no time difference between the path lengths to the listener. This gives a more linear phase alignment at the crossover band.
The horn itself is made from a marine grade molybdenum chrome alloy a material that is used in deep sea applications where structural integrity is paramount. This horn's high-mass structure is totally non resonant and extremely rigid so transients are reproduced perfectly. It's highly polished surface is plated with titanium nitride which is harder than tool steel so it will always maintain its flawless luster.
The magnet assembly is further mass enhanced by a 3mm lead disc fitted to the magnet shield. The added mass plus additional mechanical damping to this transducer put it in a class of its own for speed and definition.
The 2000 woofer
The 2000 woofer has a hard anodized aluminum cone and dust cap. Aluminum was the choice of material for a few reasons. First it has a good stiffness to mass ratio and can stay in a "pistonic" mode to a much higher frequency that just about any other material. Also, putting a thick ceramic anodized layer of aluminum oxide on the surface, the diaphragm is further rigidified with the benefit of the two differential sonic velocities in the material giving the cone a self damping characteristic as one material puts a damping constraint on the other.
Secondly aluminum has excellent heat transfer ability so the voice-coil can transfer heat up into the cone and then into the surrounding air-load. Ideally voice-coil temperature should remain as constant as possible to the ambient air temperature. However in the real world even a 50 watt power input on some voice-coils can send the temperature up 200° C within a minute or so. If the coil material is made of copper, the result can be 6dB loss in audible compression. This is known as power compression and is a major obstacle in transducer design where dynamics are concerned. This can be a very complex subject as it involves the thermal cycle of temperature rise and fall as the musical signal is transferred as power to the voice-coil. Each driver has its own parameters of a thermal cycle and is time and frequency dependant.
The third advantage that aluminum has is its acoustic opaqueness. The cone will displace air on both sides, so the acoustic output is almost equal and opposite on either side. The rear of the cone output is only used when aligned in a vented box for low frequency reinforcement. Other than that the mid range output can cause a great deal of coloration when it filters through the enclosure panels. Some of this energy is reflected off the enclosure walls and can actually penetrate through the cone itself. Aluminum has a greater opaqueness compared to any other suitable cone material resulting in improved transparency.
One of the major disadvantages of any stiff material is that when cone breakup occurs, the energy released at that point in the frequency band can be high enough to be well above the average output in the spectrum, sometimes higher than 12dB. This would certainly cause problems and additional electrical filtering may not totally eliminate this.
The AAD 2000 series woofer has a unique cone geometry which allows it to stay pistonic in its operational band and produce a very flat frequency response. Above this frequency range at 2.6 kHz the acoustic output falls off rapidly at 18db/octave. So that all cone breakup modes are severely attenuated even without filtering.
The woofer frame is die-cast from magnesium aluminum alloy. The frame has excellent rigidity and heat sinking characteristics. It has additional ventilation for heat generated in the voice-coil.
The oversized 34mm voice coil has substantial power handing . it is wound directly onto a 0.3mm black anodized ventilated aluminum coil former. This former is bonded to the cone using specifically designed heat conducting adhesive so that the whole coil-former and cone assembly acts as a heat radiator. This means the operating temperature of the voice-coil is reduced to its absolute minimum, giving are far greater dynamic range.
The large and powerful magnet assembly is shielded. It also has a 3mm lead disc fitted to it to reduce mechanical resonance.
The rubber surround and large excursion spider/damper will not fatigue under normal operating conditions. These components will actually improve with age and it is recommended that the speakers are run in for 200 hours before they start to sound at their best.
The 2000 Crossover
The back-plate is manufactured from non-magnetic stainless steel and holds the crossover components, terminals and vent in one assembly. The whole structure is dense, rigid and non resonant as it is a major part of the enclosure.
The massive air core inductors are wound directly onto the gas-flowed vent. These are low loss inductors and their resistance is almost negligible, necessary to control both transducers effectively. High-grade 400 volt polypropylene film capacitors are used throughout the circuits. All resistors are either 10 or 20 watt rating, well above what is actually required.
The terminals are custom AAD design and feature a special one-way torque setting engineered into a proprietary key.
The 2000 Enclosures
All 2000 enclosures are made from MDF 25 mm thick on front and back and 38 mm thick on sides. All enclosures use internal braces 25mm thick. Lead sheet 3mm thick is applied to each panel before assembly to further reduces panel coloration. All metal parts such as grilles, screws and inserts are custom AAD parts made from stainless steel.
Each enclosure is laminated in the most finest of exotic wood veneers and hand rubbed before lacquering.
QC & Final Inspection
Each 2000 speaker is built by hand with great care and attention. Each individual component is checked for total quality before assembly. All electrical components in the crossovers are individually measured for the exact value. Soldering is done with special care ensuring that every single electrical joint is flawless using 4% silver solder.
Before packing each loudspeaker is measured against our reference standard to be within 1 dB of the reference curve. It is also auditioned using a high grade audio source with wide dynamic and frequency program material.
STANDS LIST FOR $1200 A PAIR ...EXTRA
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