Let me explain the discrepancy between the Stereophile measurements and the Ultra Audio measurements.
John Atkinson uses a simulated anechoic technique, employing time-gating over most of the spectrum and close-miking the woofer and port in the bass region, then doing some calculating and splicing. So the deep bass response in Stereophile's measurement section is the expected anechoic response (no room contribution).
In his Ultra Audio review, Paul Messenger states that he used a "farfield in-room technique" - in other words, the room's contribution was included. This is the reason for the discrepancy.
Typical room gain for a monopolar speaker system in a home listening room is roughly 3 dB per octave below 100 Hz or so. At 20 Hz, this comes to 7 dB. Note that room gain varies from room to room. Apparently in Paul Messenger's room, and with his speaker and microphone positioning, he gets about 10 dB of room gain at 20 Hz.
Here's a link to a "typical" room-gain curve: http://www.speakerbuilding.com/content/1020/rge.gif
If we add the expected 7 dB of room gain to the -10 dB that Stereophile recorded at 20 Hz, we come up with -3 dB.
So in a real-world situation, the 802D meets Stereophile's criteria for classification as a "full-range" loudspeaker.
Duke
dealer/manufacturer
John Atkinson uses a simulated anechoic technique, employing time-gating over most of the spectrum and close-miking the woofer and port in the bass region, then doing some calculating and splicing. So the deep bass response in Stereophile's measurement section is the expected anechoic response (no room contribution).
In his Ultra Audio review, Paul Messenger states that he used a "farfield in-room technique" - in other words, the room's contribution was included. This is the reason for the discrepancy.
Typical room gain for a monopolar speaker system in a home listening room is roughly 3 dB per octave below 100 Hz or so. At 20 Hz, this comes to 7 dB. Note that room gain varies from room to room. Apparently in Paul Messenger's room, and with his speaker and microphone positioning, he gets about 10 dB of room gain at 20 Hz.
Here's a link to a "typical" room-gain curve: http://www.speakerbuilding.com/content/1020/rge.gif
If we add the expected 7 dB of room gain to the -10 dB that Stereophile recorded at 20 Hz, we come up with -3 dB.
So in a real-world situation, the 802D meets Stereophile's criteria for classification as a "full-range" loudspeaker.
Duke
dealer/manufacturer