Balanced Armature Driver D WFK-31785-000 Product Data Sheet Dual Full-range Product Features: Small size More bass-oriented than TWFK High efficiency (SPL/size) RoHS compliant Outline Drawing mm (inches) Demonstrator Earphone Model Number (standard sample in BOLD) without MIC with MIC Straight Cable TC-32211-B101 TC-32282-B101 Ordering Information: Phone: (630) 250-5100 Knowles Model Number: DWFK-31785-000 Fax: (630) 250-0575 1151 Maplewood Drive info knowles.com Itasca, Illinois 60143 knowles.comBalanced Armature Driver DWFK-31785-000 Dual Full-range Frequency Response and THD Impedance and Saturation SPL Testing Conditions Typical Performance at 1kHz Impedance 30 Ohms using 100mV rms drive signal Sensitivity to 100mV 106 dB SPL IEC60318-4 (711) coupler Sensitivity to 1mW 111 dB SPL G.R.A.S. 43BA-2 (0.4cc) a Max SPL 120 dB SPL THD THD at 94dB SPL 0.4 % THD at 100dB SPL 0.5 % Footnotes: a SPL at 10% THD Note: Ask about custom assembly options (lead wires, customer-specified materials, etc.) To prevent heat damage, follow soldering guidelines in application note AN13 (knowles.com) Measurement data for reference only. Refer to model specification for full dimensions and performance. Ordering Information: Phone: (630) 250-5100 Knowles Model Number: DWFK-31785-000 Fax: (630) 250-0575 1151 Maplewood Drive info knowles.com Itasca, Illinois 60143 knowles.com