last updated: 11th August 1996
The Pyramid W61 is a 6.5" car audio driver with a 3.25" mounting depth. The W61 is located near the bottom of Pyramid's driver range, but can produce decent performance in a small 4th order bandpass enclosure if used in an isobaric configuration. The W61 has a stamped frame, a 40 oz. magnet structure, a paper cone and a foam surround.
The Theile/Small parameters for the W61 are as follows:
Claimed : Vas=0.67 cu.ft., Qes=0.57, Qms=2.86, Qts=0.47, Fs=64.5 Hz
Measured : Vas=0.98 cu.ft., Qes=0.65, Qms=2.51, Qts=0.52, Fs=53.0 Hz