本文提出針對動圈式揚聲器的前置式補償系統。補償系統包含前置式補償器，由有限脈衝濾波器實現。為了提升低頻響應與平滑頻率響應，本文提出自適應演算法系統(Adaptive filtering system)。本文包含兩種補償方法：有感測器與無感測器的補償系統。兩系統皆為單聲道的補償系統，其中所需的控制器皆為單輸入單輸出系統(single input single output)，每一種方法包含兩種操作：離線(off-line)操作與即時(on-line)操作。因此本文有四種操作方法。離線操作求得補償器(compensator)的係數先於計算求得後，再載入數位訊號處理開發板執行。即時操作即為直接在數位訊號處理開發直接求得。本文討論模擬驗證與實驗執行，隨後提出客觀與主觀的評估測試，來衡量此補償器之效果。

This paper presents feed-forward loudspeaker compensation systems for moving-coil loudspeakers. These feed-forward compensators are realized in digital finite impulse response (FIR) filter. For the purpose of enhancing the low-frequency performance and flattening frequency response, the adaptive filtering system is proposed. This paper contains two parts: the loudspeaker compensation with and without a sensor. It presents the single channel compensation. Systems in this paper are single input single output (SISO). Each method contains off-line and on-line operation. Thus, there are 4 operations in this paper. Off-line operations obtain coefficients of compensators by calculating at off-line. On-line operations are implemented in real-time. The verification of simulations is shown in this paper. In experiments, digital signal processor (DSP) is used to implement the adaptive loudspeaker compensation system. The results of listening tests are shown in this paper. We compare 4 operations in the last section.

摘 要
ABSTRACT
誌 謝
Table of Contents
FIGURE LIST
Chapter 1 INTRODUCTION
Chapter 2 COMPENSATION WITH A SENSOR
2.1 Adaptive filtering
2.2 Compensator
Chapter 3 COMPENSATION WITHOUT A SENSOR
3.1 Loudspeaker electro-mechano-acoustical (EMA) model
3.2 Velocity estimator
Chapter 4 SIMULATIONS AND EXPERIMENTS
4.1 Verification of off-line operations
4.2 Fixed-point mathematics
4.3 Subjective tests
Chapter 5 CONCLUSIONS
REFERENCES
Appendix

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