The Speaker Tester adds acoustic measurement features required for speaker analysis and room design to the electrical measurements of the Woofer Tester 2. Its innovative approach to crossover design allows you to simulate a new crossover circuit right on your desktop and saves you considerable time by getting the design right before you build it. USB powered from your laptop, the Speaker Tester is mobile and easy to take with you to measure acoustics at a client site.
 

Included with The Speaker Tester:
• Test unit
• CD-ROM with Software
• 1 Measurement Microphone & Cable
• 1 USB A/B cable
• 2 RCA Y-cables
• 1 10-ohm 1/4 watt Calibration Resistor
• Low-power Banana/Alligator test leads
• Downloadable User Guide
• Free Software Upgrades & Support

System Requirements:
• Pentium 450 MHz or faster
• USB Port
• Windows® Vista, XP, 2000, Me or 98SE

Download Presentation     Compare Features

WTPro
Hardware Features:
• Dual XLR Microphone Inputs
• Low-level Line Input & Output
• Internal, Software Controlled Source Switching
• Self-Powered from USB port or 5V external source
• Dimensions: 6" x 4.25" x 2.25"

Description

Real-Time Acoustic Analysis (RTA)

The Speaker Tester measures in-air acoustic response with MLS, Noise, Impulse or Chirp in real-time allowing you to easily position speakers perfectly in the room. Simply move the test microphone around the room and watch the response on the screen. For Best noise rejection (Sweep and collect), use Sine and Pulsed Sine modes. Reject room reflections using a Time Window (MLS and Step) and create Cumulative Spectral Decay and Waterfall Plots.

InAirAcousticResponse.gif      Click on Images to Enlarge


Interactive Crossover Design (ICD)

The new, innovative approach to crossover design introduced by Smith & Larson Audio greatly speeds up crossover design time by allowing you to simulate various crossover designs without actually having to build them!

Designs are entered via an ICD circuit file, which is converted into filtered left and right test signals. The test signals are then used to excite two drivers connected directly to an amplifier. The results of the simulated crossover match the physical crossover to fractions of a db, as shown in the overlay of response magnitude and phase plots below. The Speaker Tester also measures driver time alignment to mm accuracy.

icd_sim_real2_small.gif


XVR Response Tool

The XVR Response Tool is used to enter response using magnitude and phase. The data is entered via a text file that specifies the parameters for right and left channels, as shown below.

         XVR Data File
  

The tool also allows you to define and simulate a perfect crossover with an ultra-sharp cutoff in order to test the behavior of a particular design. Electronic or DSP filters can be added to advanced crossover designs by defining the filter characteristics in a text file similar to the file for entering response.

             Amplitude of Both Channels
crossoverpoint4.gif


Analyzing the Crossover Point

To help you find the optimal crossover point, the Speaker Tester measures acoustic distance to <.1mm and finds delta phase at the crossover frequency. Crossovers are also affected by voice coil alignment. The ICD control window includes a time delay option to test these effects without having to physically move the drivers.

            Delta Phase at XO frequency
crossoverpoint5.gif


Support for Driver Protection Circuitry

To avoid costly mistakes and protect your drivers during the design phase, the software supports tweeter protection circuitry by reversing the response effects. The User Guide contains instructions on how to build a physical tweeter protection circuit.


Working with 3rd Party Schematic Entry Tools

Electronic circuits designed in 3rd party schematic entry tools such as Linear Technologies' LT-Spice/Switcher-Cad can be imported into the Speaker Tester via the common SPICE net-list file format.


Swept Sine Analysis

The Speaker Tester also includes traditional Swept Sine Analysis. Pure tones are most useful when measuring distortion, or when a precise frequency and level measurement is needed.

Harmonic distortion occurs when a pure sine wave is applied to a non linear device such as a speaker and overtones at integer multiples of the applied signal frequency are produced. The relative strength of each harmonic is usually expressed as a measurement of the ratio to the fundamental or on an absolute scale. The tester also produces a measurement ratio of the signal to the sum of all noise and distortion or SINAD.

Pure tones are advantageous in that they are easily isolated from background sounds making them ideal when large dynamic ranges are needed. They are also ideally suited for measuring resonance points since the applied and measured frequency is non ambiguous (Fourier methods must interpolate their results), or when standing waves are not an issue. An anechoic chamber or close mike measurement of a woofer would be two examples.

Harmonic, Inter-Modulation & SINAD Distortion Measurement

The Speaker Tester includes various distortion measurements: 1st through 6th Harmonics on a relative or absolute level vs. frequency, inter-modulation distortion as well as Signal to Noise and Distortion Ratio (SINAD). SINAD can be viewed as Signal Relative To Drive Signal, Oscilloscope or Lissajoux.

Tweeter Response & Harmonics 1-6 on Absolute Scale         SINAD at 1 kHz Shown as Lissajoux Pattern
harmonics.gif sinad.gif

Test Signals

The Speaker Tester supports MLS, Step, Noise, Chirp, Continuous Sine and Pulsed Sine modes for accurate as well as fast testing. High precision measurements are crucial for modeling and the Continuous Sine mode provides the best signal to noise ratio. With the Speaker Tester, results are as accurate as .02%. Continuous Sine mode is best used for close microphone response or within an anechoic chamber.

MLS and Step modes are intended for real-time testing. The Speaker Tester conducts fast tests in under 1 second. The Step mode favors lower frequencies and is best suited for woofers, while MLS is better suited for midranges and tweeters.


Advanced Thiele-Small Simulator & Box Analyzer

The advanced Thiele-Small simulator in the Speaker Tester supports all box types - Vented, Sealed, Band Pass and Passive Radiator. Using Frequency Dependent Inductance modeling, results are improved over the traditional, tabular method. The simulator measures Response, Impedance, Phase, Velocity & Xmm of all Radiators.

The Box Analyzer automatically finds box alignment and losses with the built-in Auto-Align feature. It calculates box, port and stuffing losses and models the effects of room/car pressurization as well as vent resonance (pipe organ effects). Import your data from the Speaker Tester Test Environment or the manufacturer's data sheet. You can also import T/S versus Drive Level test data.

Compare simulated to real-time response with extreme precision (< 0.5dB error) as shown in the graph below:

boxalign.gif





$649.95





  Do you already own a WT2?

  Click here for upgrade offers



Features:

• Real-Time Acoustic Analysis

• MLS, Noise, Impulse & Chirp
  test signals

• 2K through 256K samples

• Cumulative Spectral Decay
  and Sliding Window
  Waterfall Display

• Reject Room Reflections
  using Time Gated
  Impulse Response

• Swept Sine Analysis

• Achieves very high signal to
  noise ratio using matched
  DSP filters

• THD, IM and SINAD
  Distortion Measurement

• Thiele-Small Electrical
  RLC Testing up to 3mA drive

• Mobile, USB Powered
  from Laptop

• Upgrade Path
  WTPro


Copyright © 2008 CS Audio, Inc. All Rights Reserved. | Trademarks | Privacy Policy
Website by FinTree - www.fintree.com