SW178WA01


	SW178WA01 is a woofer designed for dedicated subwoofer applications. It works equally well for high-end hi-fi, high quality home theater systems, and top multimedia setups. The extremely stiff aluminium cone, the long linear throw, exaggerated ventilation, and the special dynamic linearization short circuiting ring together makes up for an unusually linear and low-distortion woofer. Even at very high signal levels, the unit behaves controlled and without distortion. Due to very low mechanical losses SW178WA01 masters equally well low level details and dynamic requirements.

		FEATURES




		Frequency resp. Specifications Dimensions Ordering info

Very rigid aluminium cone to ensure piston motion at high levels and for better heat transfer at high continuous power levels
Vented voice coil former for reduced distortion and compression
Vented center pole with dual flares for reduced noise level at large cone excursions
Vented chassis for lower air flow speed reducing audible distortion
Heavy-duty black fiber glass voice coil bobbin to reduce mechanical losses resulting in better dynamic performance and low-level details
Large motor system with 1.5” voice coil diameter and 110mm magnet for better control and efficiency
Built-in alu field-stabilizing ring for reduced high-level distortion
Long linear stroke motor for reduced distortion at high levels
Linear suspension with specially designed CONEX damper (spider) for long durability under extreme operating conditions
4-layer voice coil for increased control and better small-cabinet performance
Gold plated terminals to prevent oxidation for long-term reliable connection
Sealing gasket pre-attached for hassle-free mounting and secure cabinet sealing


	FREQUENCY RESPONSE


	Measuring conditions, SPL Driver mounting: Flush in infinite baffle, back side open (no cabinet) Microphone distance: 1.0 m Input signal: 2.83 VRMS stepped sine wave Smoothing: 1/6 oct.


	Measuring conditions, impedance Driver mounting: Free air, no baffle, back side open (no cabinet) Input signal: Stepped sine wave, semi- current-drive, nominal current 2 mA Smoothing: None


	NOMINAL SPECIFICATIONS

Notes	Parameter	Before burn-in	After burn-in	Unit
	Nominal size	7		[inch.]
	Nominal impedance	8		[ohm]
	Recommended max. upper frequency limit	600		[Hz]
1, 3	Sensitivity, 2.83V/1m (calculated from T/S parameters)	85		[dB]
2	Power handling, short term, IEC 268-5, no additional filtering			[W]
2	Power handling, long term, IEC 268-5, no additional filtering			[W]
2	Power handling, continuous, IEC 268-5, no additional filtering	100		[W]
	Effective radiating area, Sd	131		[sq.cm]
3, 6	Resonance frequency (free air, no baffle), Fs	38	36	[Hz]
	Moving mass, incl. air (free air, no baffle), Mms	35		[g]
3	Force factor, Bxl	12.0		[N/A]
3, 6	Suspension compliance, Cms	0.50	0.56	[mm/N]
3, 6	Equivalent air volume, Vas	12.2	13.6	[lit.]
3, 6	Mechanical Q, Qms	19.3	18.4	[-]
3, 6	Electrical Q, Qes	0.37	0.35	[-]
3, 6	Total Q, Qts	0.365	0.346	[-]
4	Voice coil resistance, RDC	6.4		[ohm]
5	Voice coil inductance, Le (measured at 1 kHz)	2.2		[mH]
	Voice coil inside diameter	39		[mm]
	Voice coil winding height	16		[mm]
	Air gap height	6		[mm]
	Magnet weight	680		[g]
	Total unit net weight excl. packaging	1.81		[kg]
3, 5	Krm			[mohm]
3, 5	Erm			[-]
3, 5	Kxm			[mH]
3, 5	Exm			[-]

Note 1	Measured in infinite baffle.
Note 2	Tested in free air (no cabinet).
Note 3	Measured using a semi-constant current source, nominal level 2 mA.
Note 4	Measured at 25 deg. C
Note 5	It is generally a rough simplification to assume that loudspeaker transducer voice coils exhibit the characteristics of an inductor. Instead it is a far more accurate approach to use the more advanced model often referred to as the “Wright empirical model”, also used in LEAP-4 as the TSL model (www.linearx.com), involving parameters Krm, Erm, Kxm, and Exm. This more accurate transducer model is described in a technical paper (PDF) here.
Note 6	After burn-in specifications are measured 12 hours after exiting the transducer by a 20 Hz sine wave for 2 hours at level 14.1 VRMS. The unit is not burned in before shipping.


	OUTLINE DRAWING AND NOMINAL DIMENSIONS (mm)


	TERMINAL NOMINAL DIMENSIONS (mm)


	PACKAGING AND ORDERING INFORMATION

Part no. SW178WA01-01	Individual packaging (one piece per box)
Part no. SW178WA01-02	Bulk packaging


	Latest update: Nov. 25, 2019

MORE INFO

PDF data sheet

Cross section/ exploded view