Dipole Baffle: BG55 Chifon
The Listening Room Measurements

The Impulse response, Phase response and Frequency response shown on this page are from the RD-75 driver whose serial number ends in the digits '55'. The measurements were taken at distance of 2 meters from the baffle, and 1 meter from the floor. The baffle in the photo at left is not tilted, it is an artifact of the photo. The baffle boards are standard U.S. sized 1" x 8" Clear Douglas Fir (actual size ~ 0.75" x 7.125"). Acoustic damping was added with a sheet of 'chifon' fabric stretched tightly across the front of the driver.

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.

BAFFLE DIMENSIONS:
Height: 75.6"
Top width: 17.75"
Base width: 17.75" - Sides~ 7.125"
Thickness: ~0.75" Square edges

The Listening Room Measurements - Baffle: BG55.
The Listening Room Measurements - Comparison: Drivers 54 & 55, Bare board baffles.
The Listening Room Measurements - Two-Sided Baffles - Table of Contents.
Acoustic Line Source Research - Table of Contents.