Κώστας Φ.
Truth hurts. Here's a teddy bear.
- Μηνύματα
- 8.978
- Reaction score
- 895
Specifications
- Type: Electrostatic loudspeakers
- Frequency Response: 38Hz to 20kHz (± 3dB)
- Sensitivity: 86dB/W/m
- Nominal Impedance: 4 Ohms
- Recommended Amplifier Power: At least 75 wpc
- Dimensions: 78.3 x 14.2 x 2 (HxWxD in inches)
- Weight: 50.5 lbs each
- Price: $9,999/Pair (Chrome Finish); $11,000/Pair in Piano Black
The 1000i represents Final's flagship product, a 6.5-foot tall line source.
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Conventional electrostatics apply the DC bias voltage to the central diaphragm, typically a thin conductive Mylar film, that is sandwiched between acoustically transparent stator panels (e.g., perforated metal plates). The audio signal is stepped up to a high voltage by the input transformer and applied to each stator with opposite polarity. The resultant electrostatic forces applied over the diaphragm's area cause it to be pushed and pulled in unison toward the stators.
Final Sound inverts the function of the transducer elements, a design patented under the name "Inverter Technology." The audio signal is applied to a 12 micron thin diaphragm which is made conductive via a proprietary coating process that also makes it resistant to environmental contaminants. The perforated metal stators are insulated with a coating of special epoxy polyester. One of the benefits of this technology is enhanced safety: no high-voltage AC signal is applied to the stator panels; the point being that a DC polarizing voltage stresses the insulation far less than would an AC signal. Another significant advantage is that the required input transformer size decreases, as the stepped-up audio signal can now be applied just to the diaphragm in single-ended fashion. Recall that traditional designs require a push-pull signal for the stator panels, and hence a beefier transformer core. Final has developed its own high-grade audio transformers partly because they have been unable to identify suitable off-the-shelf transformers, but mainly because this is a critical component, largely responsible for the overall performance of the speaker.
Several other design elements are worth our attention. There are two audio inputs to the diaphragm. The conductive layer features a separate narrow treble strip, which is being driven from its own transformer secondary winding. This improves treble dispersion and reduces the load capacitance at high frequencies. Spacers are used to break up the diaphragm into several regions for resonance control. In addition, and this idea is both new and patented, the spacing between the stators and the diaphragm at the bass side of the panel is greater than that at the treble side. Recall that electrostatic forces decrease as the square of the distance. Doubling the spacing requires a force four times as large to maintain the same efficiency. Final's technology significantly increases bass excursion capability without reducing efficiency in the midrange and treble.
Conventional electrostatics dip well below 2 Ohms in the extreme treble. It's a function of the panel being essentially a giant capacitor, which rapidly drops in impedance with increasing frequency. The higher the panel's capacitance the worse the problem becomes. The 1000i (as well as the other ESLs in the line) bucks the trend and maintains a respectable minimum impedance in the extreme treble. Ronald Buining, one of Final's designers and engineers, explained that since the treble is emitted by a narrow strip, the speaker's capacitive loading is reduced. And it is primarily the reduced capacitance that is responsible for the impedance magnitude remaining at about 2 Ohm around 20kHz for the 1000i. I agree with his take that such an impedance magnitude should not give amplifiers trouble in terms of power delivery as the music's power spectrum drops steadily with increasing frequency. There simply isn't much energy in the treble to begin with. However, it is still important to mate the 1000i with low source-impedance power amplifiers to minimize frequency response deviations due to interactions of the power amplifier's source impedance with the speaker's impedance curve. High source impedance tube amplifiers could easily result in treble loss with this speaker. In the bass, the impedance is generally above 10 Ohms with a prominent peak of 100 Ohms around 40Hz, again an easy load for a power amplifier.
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Conclusion
To my way of thinking, the Final Sound 1000i represents a milestone in the evolution of the electrostatic loudspeaker. It is a reliable, real-world ESL, whose musically expressive personality has won me over in spades. Its harmonic purity, tonal realism, and dynamic range meet the needs of most musical genres. If I had to live with only a single ESL - cost no object - the 1000i would be my top pick. A must audition for any ESL aficionado and anyone serious about approaching the live experience at home.
Full Review: enjoythemusic.com
