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: The BP-8080ST loudspeaker shows a frequency-response anomaly between 200 and 500Hz when the measurement microphone is placed in front or to the rear of the cabinet. This is because of how the midrange drivers are configured -- the soundwaves they produce “wrap around” the cabinet, causing cancellations in front of and behind it. Because of this, we performed additional frequency-response measurements on a customized speaker supplied by Definitive Technology that allowed us to measure the combined output of the tweeter and midrange drivers on the front baffle, to get a better indication of the speaker’s true frequency response. We also supplied a measurement of this customized speaker’s bass output only. We published these additional graphs below in the “Frequency Response and Sensitivity” section (charts C and D).

Because the BP-8080ST also displayed quite-low distortion at levels of 90 and 95dB, we published additional graphs of “Total Harmonic Distortion + Noise” and “Deviation from Linearity” at levels of 100dB, which we don’t normally do.


Microphone measuring position: tweeter axis
Grille: on
Woofer control: "11 o'clock"

Frequency response and sensitivity

Sensitivity: 89.52dB (averaged 300Hz-3kHz, 2.83V/1m)

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

Chart C (customized speaker): 20Hz - 20kHz (measured @ 2m, plotted @ 1m)

Midrange and tweeter output, front baffl

Curve: on-axis response from tweeter and midrange drivers on front baffle only

Chart D (customized speaker): 20Hz - 20kHz (measured @ 2m, plotted @ 1m)

Woofer response

Curve: on-axis response from bass section only

Listening window

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

Total harmonic distortion + noise

Chart A: @ 90dB, 50Hz - 10kHz (measured @ 2m)


Top curve: frequency response @ 90dB SPL
Bottom curve: THD+N @ 90dB (50Hz - 10kHz)

Chart B: @ 95dB, 50Hz - 10kHz (measured @ 2m)


Top curve: frequency response @ 95dB SPL
Bottom curve: THD+N @ 95dB (50Hz - 10kHz)

Chart C: @ 100dB, 50Hz - 10kHz (measured @ 2m)


Top curve: frequency response @ 100dB SPL
Bottom curve: THD+N @ 100dB (50Hz - 10kHz)

Deviation from linearity

Chart A: Difference @ 90dB from 70dB, 50Hz - 20kHz (measured @ 2m)


Chart B: Difference @ 95dB from 70dB, 50Hz - 20kHz (measured @ 2m)


Chart C: Difference @ 100dB from 70dB, 50Hz - 20kHz (measured @ 2m)


Impedance magnitude variation


Vertical axis: impedance
Horizontal axis: frequency

Electrical phase


Vertical axis: phase
Horizontal axis: frequency