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.
The PTT4.0X08-NAC-03 features:
Vibroacoustic optimized cone and dust cap in black anodized aluminum
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
8Ω
Cone material
Black Anodized Aluminum
Linear excursion, Xlin
±8.8mm
Maximum mechanical excursion, Xmax
±13.7mm
Motor efficiency factor, Beta
7.5 (N/A)^2/Ω
Efficiency Bandwidth Product, EBP
110.3Hz
Long term maximum power
200W
Rated noise power, 100h
60W
Electrical & Acoustical Parameter
DC resistance
6.5Ω
Minimum impedance above resonance, Zmin
7.3Ω
Frequency for minimum impedance, fmin
256Hz
Maximum impedance, Zo
69Ω
Voice Coil inductance @ 1kHz 0mm, Le
0.56mH
SPL @ 2.83Vrms/1m, 300-800Hz
81.8dB
SPL @ 1W/1m, 300-800Hz
81.4dB
Thiele/Small Paramters
Resonance frequency, fs
43Hz
Mechanical Q factor, Qms
4.1
Electrical Q factor, Qes
0.43
Total Q factor, Qts
0.39
Equivalent volume, Vas
5.3L
Effective piston area, Sd
56.7cm2
Effective piston diameter, D
8.5cm
Force factor, Bl
7.0N/A
Mechanical resistance, Rms
0.79kg/s
Moving mass, Mms
11.9g
Suspension compliance, Cms
1.16mm/N
Typical Box Tunings
Typical corner frequency, sealed B2 alignment
78.0Hz
Box volume, sealed B2 alignment
2.3L
Typical corner frequency, bass reflex PTT alignment