The Impulse, Phase and Frequency responses are from an RD-75, serial number ending in '54'. The measurements were taken at distances of 1, 2, 3, 3.5 meters and 9 feet, and 1 meter height. The baffle is named for the driver being at the extreme edge of a rectangular baffle, and having a 9" base right triangle added to the '1SR' baffle.
Details of the measurement process are to be found in the Measurements
section. The required passive notch filter was in circuit with the driver
during the measurement. Additionally, a non-standard slope 2nd order
(12dB/oct) active filter set to a -3dB point of 150Hz was also in circuit.
The rising phase response below 1000Hz reflects this fact.
The following comparison of the 1m, 2m, 3m, 3.5m and 9 foot responses of
the '1S9T' baffle are 1/3 octave smoothed in order to facilitate
evaluation. The following individual plots of the distance
measurements are 1/12 octave smoothed. They will look slightly different
from that shown in the comparison.
1 meter response, 1/12 octave smoothed.
2 meter response, 1/12 octave smoothed.
9 foot response, 1/12 octave smoothed.
3 meter response, 1/12 octave smoothed.
3.5 meter response, 1/12 octave smoothed.
Top width: 12.0"
Base width: 21.25"
Thickness: ~1.56" Half-round edge/baffle side, Half-round edge/driver side.
Baffle: 1S6T.
Comparison: One-sided Trapezoid baffles at 3 meters.
Table of Contents - One-Sided Baffles.
Table of Contents - Main Menu.
