EZ-PHASE-2™
Speaker Polarity and Cable Tester

The EZ-PHASE-2 system is a tool that helps to eliminate a basic problem associated with the installation of any type of sound equipment. You can test for absolute phase of amplifiers, equalizers, processors, loudspeaker systems, components like tweeters, drivers, woofers, and also cables on a complete sound system.

The EZ-PHASE-2 consists of two devices, a pulse generator unit and a pulse detector, and both units are necessary. The EX-PHASE II Generator, is a pulse generator, which produces a special electrical signal necessary to drive any transducer either directly or through a power amplifier. The EZ-PHASE II generator's signal covers the complete audio frequency spectrum (20 Hz-20kHz). The detector unit is the complimentary unit which detects the pulses generated by the generator unit.

The EZ-PHASE-2 polarity test system has been designed to detect ABSOLUTE phase. This means it will NOT be affected by changes of phase in individual frequencies and their harmonics. (Example: By changing the EQ settings). It will detect a change of phase ONLY if the polarity of the signal is inverted or if the mechanical rotation of the transducer changes 180 degrees.

THEORY OF OPERATION

The EZ-PHASE-2 Phase/Polarity tester measures the initial rise and peak amplitude of a repetitive acoustic pulse to determine and indicate the absolute polarity of the acoustic phase. A repetitive test pulse signal with a fast rise time and known polarity is applied to the loudspeaker under test. The tester contains special discriminating circuitry to minimize the influence of loudspeaker transient distortion, which may vary greatly from speaker to speaker. The EZ-PHASE-2 detector's unique circuitry screens distortion and loudspeaker "pre-shoot" to eliminate a potential source of false polarity indication.

To check acoustical or electrical phasing the generator (transmitter) is connected to the input of the device under test. The detector (receiver) is used to pick up the output signal. The detector section processes the information and decides whether the device under test reverses signal phase or not. The results are displayed via two LED's. GREEN indicates POSITIVE phase and RED indicates NEGATIVE phase.

The pulse generator has an amber LED to indicate when the generator is in operation. Both the generator and detector are each powered by four "AA" 1.5volt batteries.

The detector has a small gain potentiometer to control the input sensitivity level. By using a small screwdriver, turning the pot clockwise will increase the gain and turning counterclockwise will reduce the gain.

EZ-PHASE-2 Detector Specifications

LED indication: 300 mS duration during pulse.
GREEN indicates positive (out-going) polarity
RED indicates negative (in-going) polarity.
Polarity: Selectable positive going: PIN 2=HOT, or PIN3=HOT.
Required Acoustic Level at detector: Useful range 75 dBc to greater than 120 dBc.
Batteries: 4 "AA" type 1.5 volts.
Battery Drain: 16 mA instantaneous peak.
Battery Life: approximately 245 hours.

EZ-PHASE-2 Generator Specifications

Repetition Rate: 1 second.
Polarity: Selectable positive-going.
Amplitude: 0.5 volts peak.
Rise Time: 400 microseconds.
Fall Time: 11 milliseconds.
Duty Cycle: 0.9%
Source Impedance: 8 Ohms nominal.
Battery Life: approximately 416 hours.
Weight: 405 grams.
Dimensions (H x W x D) 37mm x 41mm x 155mm.