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TUNING REPORT DANIEL SERUNJOGI TRANSDUCER THEORY 1

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Page 1: · Web viewFigure 17: Tweeter harmonic distortion Figure 18: Tweeter waterfall plot Woofer Performance Figure 19: Woofer with crossover. Figure 20: Woofer Horizontal axis. Purlple:

TUNING REPORT DANIEL SERUNJOGI TRANSDUCER THEORY

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Page 2: · Web viewFigure 17: Tweeter harmonic distortion Figure 18: Tweeter waterfall plot Woofer Performance Figure 19: Woofer with crossover. Figure 20: Woofer Horizontal axis. Purlple:

Overview

The speakers I built, the DKS 800, had design goals that were aimed towards general listening.

This required the speakers to have an even sound as well as cover as much as possible the full

spectrum of hearing. Coloration of sound and distortion were to be avoided as much as

possible.

The DKS 800 were designed to be two way, medium sized stereo pair. They had a 2nd order

Linkwitz-Riley crossover cover the hearing spectrum from around 100 Hz to 30 KHz.

This document covers the results and the process of what was done to reach these goals.

Testing equipment included a Mac Mini, the MOTU interface, and a speaker testing software

program called Fuzzmeasure, which provided the graphs in this document. The speakers were

tested five feet off the ground with a testing microphone one yard directly in front of it. In

between the microphone and the speaker being tested were two flat panel absorbers to

minimize the sound of floor bounce. The testing was done in McArdle theatre, which has inbuilt

dampening curtains that were used as well to minimize echo.

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Page 3: · Web viewFigure 17: Tweeter harmonic distortion Figure 18: Tweeter waterfall plot Woofer Performance Figure 19: Woofer with crossover. Figure 20: Woofer Horizontal axis. Purlple:

Initial Testing and Crossover Configuration

Figure 1: This was my initial test of my loudspeaker box. As can clearly be seen, there is a

Extreme drop from 1K downwards and there is a very high peak right after 10K. Both of these

were problems were resolved. The dip was fixed after I rearranged the dampening material and

the peak after 10K was resolved after applying the microphone calibration.

Figure 2: Tweeter with no crossover.

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Page 4: · Web viewFigure 17: Tweeter harmonic distortion Figure 18: Tweeter waterfall plot Woofer Performance Figure 19: Woofer with crossover. Figure 20: Woofer Horizontal axis. Purlple:

Figure 3: Woofer with no crossover.

Final Testing

Figure 4: This is the overall final frequency response. I made my crossover point at 3K and the microphone calibration took care of the large peak after 10K.

Figure 5: This is the impulse response of the entire system. Red: 0 degrees,

Purlple: 15 degrees, Blue: 30 degrees, Green: 45 degrees, Yellow: 60 degrees.

Figure 6: Difference of left and right speaker.

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Page 5: · Web viewFigure 17: Tweeter harmonic distortion Figure 18: Tweeter waterfall plot Woofer Performance Figure 19: Woofer with crossover. Figure 20: Woofer Horizontal axis. Purlple:

Figure 7: Minimum Phase of entire system.

Figure 8: Step Response for entire system. (Vertical Axis) Red: 0 degrees,

Purlple: 15 degrees, Blue: 30 degrees, Green: 45 degrees, Yellow: 60 degrees.

Figure 9: Entire system (Vertical Axis) Red: 0 degrees, Purlple: 15 degrees, Blue: 30 degrees, Green: 45 degrees, Yellow: 60 degrees.

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Page 6: · Web viewFigure 17: Tweeter harmonic distortion Figure 18: Tweeter waterfall plot Woofer Performance Figure 19: Woofer with crossover. Figure 20: Woofer Horizontal axis. Purlple:

Figure 10: Waterfall plot of entire system.

Figure 11: Harmonic Distortion for entire system.

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Page 7: · Web viewFigure 17: Tweeter harmonic distortion Figure 18: Tweeter waterfall plot Woofer Performance Figure 19: Woofer with crossover. Figure 20: Woofer Horizontal axis. Purlple:

Figure 12: Entire system horizontal axis. Purlple: 0 degrees, Red: 15 degrees, Green: 30 degrees, Blue: 45 degrees, Yellow: 60 degrees.

Tweeter Performance

Figure 13: Tweeter with crossover.

Figure 14: Tweeter vertical axis. Red: 15 degrees, Green: 30 degrees, Blue: 45 degrees,

Yellow: 60 degrees.

Figure 15: Tweeter impulse response. Purple 0 degrees, Red: 15 degrees, Green: 30 degrees, Blue 45 degrees, Yellow: 60 degrees.

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Page 8: · Web viewFigure 17: Tweeter harmonic distortion Figure 18: Tweeter waterfall plot Woofer Performance Figure 19: Woofer with crossover. Figure 20: Woofer Horizontal axis. Purlple:

Figure 16: Tweeter horizontal axis. Green: 0 degrees, , Red: 15 degrees, Purlple: 30 degrees, Blue: 45 degrees, Yellow: 60 degrees.

Figure 17: Tweeter harmonic distortion

Figure 18: Tweeter waterfall plot

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Page 9: · Web viewFigure 17: Tweeter harmonic distortion Figure 18: Tweeter waterfall plot Woofer Performance Figure 19: Woofer with crossover. Figure 20: Woofer Horizontal axis. Purlple:

Woofer Performance

Figure 19: Woofer with crossover.

Figure 20: Woofer Horizontal axis. Purlple: 0 degrees, Red: 15 degrees, Green: 30 degrees, Blue: 45 degrees, Yellow: 60 degrees.

Figure 21: Woofer horizontal axis Purlple: 0 degrees, Red: 15 degrees, Green: 30 degrees, Blue: 45 degrees, Yellow: 60 degrees.

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Page 10: · Web viewFigure 17: Tweeter harmonic distortion Figure 18: Tweeter waterfall plot Woofer Performance Figure 19: Woofer with crossover. Figure 20: Woofer Horizontal axis. Purlple:

Figure 22: Woofer harmonic distortion.

Figure 23: Woofer step response. Purple: 0 degrees, Red: 15 degrees, Green: 30 degrees, Blue: 45 degrees, Yellow: 60 degrees.

Figure 24: Woofer minimum phase

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Page 11: · Web viewFigure 17: Tweeter harmonic distortion Figure 18: Tweeter waterfall plot Woofer Performance Figure 19: Woofer with crossover. Figure 20: Woofer Horizontal axis. Purlple:

Figure 25: Woofer vertical axis. Purple: 0 degrees, Green: 15 degrees, Red: 30 degrees, Blue: 45 degrees, Yellow: 60 degrees.

Figure 26: Woofer waterfall system.

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