***CURRENTLY, ALL PURIFI DRIVERS ARE MADE TO ORDER WITH EXPECTED DELIVERY WITHIN 8-12 WEEKS***
Description:
The 4” long-stroke driver incorporates the easily recognizable PURIFI NeutralSurround suspension and ultra-linear motor system PURIFI PureDrive technology working in concert to elevate performance to a whole new level despite of it’s compact size.
Features:
Vibroacoustic optimized cone and dust cap in proprietary paper fiber mix
Negligible Force Factor Modulation (FFM) and Surround Radiation Distortion (SRD)
Low Magnetic Hysteresis Distortion (MHD)
"Real" long-stroke performance with distortion remaining low over full excursion
Uncompromised midrange performance
Designed and manufactured in Denmark
Specifications:
General Specifications
Type
Extended Woofer
Size
4in
Nominal impedance
4Ω
Cone material
Proprietary Fiber Mix
Linear excursion, Xlin
±8.8mm
Maximum mechanical excursion, Xmax
±13.7mm
Motor efficiency factor, Beta
9.5 (N/A)^2/Ω
Efficiency Bandwidth Product, EBP
126.7Hz
Long term maximum power
200W
Rated noise power, 100h
60W
Electrical & Acoustical Parameter
DC resistance
3.8Ω
Minimum impedance above resonance, Zmin
4.3Ω
Frequency for minimum impedance, fmin
262Hz
Maximum impedance, Zo
58Ω
Voice Coil inductance @ 1kHz 0mm, Le
0.38mH
SPL @ 2.83Vrms/1m, 300-800Hz
84.5dB
SPL @ 1W/1m, 300-800Hz
81.8dB
Thiele/Small Parameters
Resonance frequency, fs
38Hz
Mechanical Q factor, Qms
4.5
Electrical Q factor, Qes
0.32
Total Q factor, Qts
0.3
Equivalent volume, Vas
6.4L
Effective piston area, Sd
56.7cm2
Effective piston diameter, D
8.5cm
Force factor, Bl
6.0N/A
Mechanical resistance, Rms
0.66kg/s
Moving mass, Mms
12.8g
Suspension compliance, Cms
1.41mm/N
Typical Box Tunings
Typical corner frequency, sealed B2 alignment
89.6Hz
Box volume, sealed B2 alignment
1.4L
Typical corner frequency, bass reflex PTT alignment