Three Purifi-Audio PTT6.5W08-01B

I recently upgraded to the mid-range version of this Purifi- Audio driver for my LRC in my theater. I am now selling (3) of the PTT6.5W08-01B. These 6.5” drivers truly cracks the long-stroke code. They have been mounted in a vented box, and feed with a high quality crossover that crossed them over at 250 and 1500hz. This sale is for the drivers only. Perfect for a LRC 2-way speaker builder. Or purchase these three, and purchase a 4th one for a D'Appolito design.   PURIFI’s research has identified the parameters that have so far prevented long stroke drivers from breaking through in truly high performance audio. The distortion of the acoustic output of a driver is a combination of several separate distortion mechanisms in the motor, cone and suspension. When testing a complete driver with sine waves, a situation often arises where a small tweak seemingly improves harmonic distortion (HD) by letting two mechanisms counteract each other. This always leads to a clear worsening of intermodulation distortion (IMD) that becomes obvious when testing the unit with a more complex signal. This is why traditional HD tests fail to predict subjective sound quality. PURIFI takes care to optimize the various distortion mechanisms separately, thus guaranteeing that any measured improvement truly reflects a real audible improvement no matter what the signal is. Accurate mathematical models are developed for the motor, suspension and the vibroacoustics of the dome and surround. These models clearly explain several distortion mechanisms in each domain, which provides fundamental insights into better ways of constructing the motor, cone and suspension. Finally, the same models are used to numerically fine-tune the geometry. This way of working reliably reduces multiple distortions mechanisms which secures low IMD for complex signals.