All loudspeaker measurements are performed independently at the National Research Council of Canada. All measurement data and graphical information displayed below are the property of the SoundStage! Network and Schneider Publishing Inc. Reproduction in any format is not permitted.
Notes: Because the Devialet Gold Phantom is self-powered, the usual measurements of sensitivity, impedance, and electrical phase are not applicable, and so are not included here. (They are relevant only for speakers that require external amplification.) Furthermore, since the Gold Phantom has a digital crossover that introduces latency (time delay), we could not perform our typical distortion measurements, as our analyzer could not cope with the delay.
Normally, frequency-response measurements are performed with a 2.83V analog input signal from an amplifier, which is equivalent to 1W into 8 ohms. But since the Gold Phantom is self-powered and accepts only digital signals, we first had to convert the analog output from our test system to digital by using an external analog-to-digital converter, its output then sent from the ADC to the Gold Phantom via a TosLink connection. We used Devialet’s Spark app to control the Gold Phantom’s built-in volume control via Bluetooth, and set the speaker’s sound-pressure level (SPL) across the range of 300-1500Hz to about 86dB (at 1m), which we’ve found to be the average SPL of conventional speakers we’ve measured using a 2.83V input. Using the 86dB output level worked well to measure the Gold Phantom’s Deviation from Linearity, which was first measured at 80dB, as this measurement is plotted at a distance of 2m. Because each doubling of the distance reduces the measured output by 6dB, 86dB at 1m is equivalent to 80dB at 2m. (Conversely, each halving of distance increases measured output by 6dB.) A second Deviation from Linearity, performed at 90dB, the typical level we use, is also included here.
Microphone measuring position: tweeter axis
Chart A: 20Hz - 20kHz (measured @ 2m, plotted @ 1m)
Top curve: on-axis response
Middle curve: 15 degrees off-axis response
Bottom curve: 30 degrees off-axis response
Chart B: 20Hz - 20kHz (measured @ 2m, plotted @ 1m)
Top curve: 45 degrees off-axis response
Middle curve: 60 degrees off-axis response
Bottom curve: 75 degrees off-axis response
20Hz - 20kHz (measured @ 2m, plotted @ 1m)
Response curve is an average of five measurements: on-axis, 15 degrees left and right off-axis, 15 degrees up and down off-axis
Deviation from linearity
Chart A: Difference @ 80dB from 70dB, 50Hz - 20kHz (measured @ 2m)
Chart B: Difference @ 90dB from 70dB, 50Hz - 20kHz (measured @ 2m)