本論文為以共振峰頻率資料來研究海陸腔客語母音音質之聲學研究。 語言學的文獻中，以共振峰頻率資料來研究世界上各種語言的母音的音質已經有相當豐富的文獻，在過去五十年來，前人在客語的語音及音韻系統上已經有豐富的研究成果。但以聲學資料來對海陸客語做描述的文獻相當缺乏。 本研究的受試者為居住在新竹縣新埔鎮，六位以海陸腔客家話為母語的人士，其中有三名男性及三名女性。本研究使用了32個測試字，包含了單元音、雙合元音及三合元音。語音資料是利用KAY CSL 4100 (KAY Electronics)來做分析。本研究測試字包含的音節結構有:CV, CVV, CVVC, CVC, 以及CVVV。測試字在實驗的過程中，被受試者單獨發音，或是放在句子中間。在實驗資料完成分析後，我們以Origin 6.0軟體繪出海陸腔客語母音的聲學空間圖。 根據供振峰研究資料，本研究得到以下有關海陸腔客語母音音質的表現。首先關於單元音，海陸腔客語共有六個單元音: [i], [e], [ɨ], [a], [o], 以及 [u]。其次，海陸腔客語共有十一個雙元音: [ie], [ia], [io], [iu], [eu], [ai], [au], [oi], [ui], [ue], 以及 [ua]。我們比較單元音及雙元音的聲學空間圖(vowel space)後，發現相同的母音在雙母音的環境下，由於受到鄰近母音發音位置的影響，在聲學空間上，比起在單母音的時候，變的更高低，或更前或後。第三，三母音[iai], [iau]和[uai]在聲譜圖上的表現，第一個母音[i]和[u]都比其後的兩個母音，長度來的相對的短一些，表現很像是滑音[j]和[w]。 最後，本研究以共振峰聲學頻率的形式描述及記錄了當代海陸腔客語母音的音質，前人的研究中，以楊時逢(1952)最能說明本研究所提供的聲學資料。希望這些資料能對海陸腔客語母音的研究有所貢獻。 / This thesis is an acoustic study that investigates the vowel quality of Hai-lu Hakka vowels with formant frequency data. The acoustic method has been widely applied to the study of vowel quality of languages worldwide. In the past 50 years, Hakka researchers have yielded rich results in phonological system and phonetic description of Hakka, but there are relatively fewer research focus on the acoustic properties and characteristics of vowel phones in Hai-lu Hakka. The subjects of this study included three male and three female native Hai-lu Hakka speakers. Testing items used in this study were 32 syllables that involve monophthongs, diphthongs, and triphthongs. The speech data were analyzed by using KAY CSL 4100 (KAY Electronics). The data discussed in this study were testing items produced in citation form and sentence form, including the following syllable structures: CV, CVC, CVV, CVVC, and CVVV. The vowel qualities of Hai-lu Hakka vowels were measured and analyzed, and the acoustic vowel space of Hai-lu Hakka is plotted by the software Origin 6.0. Several results concerning the vowel quality of Hai-lu Hakka vowels were reported based on the formant frequency data. Firstly, there are six monophthongs in the vowel system of Hailu Hakka: [i], [e], [ɨ], [a], [o], and [u]. Secondly, there are eleven diphthongs in the vowel system of Hai-lu Hakka : [ie], [ia], [io], [iu], [eu], [ai], [au], [oi], [ui], [ue], and [ua]. By comparing the relative position of the vowel in a diphthong and the corresponding vowel as in a monophthong, we found that the second vowel in a diphthong tend to be higher or lower, more fontal or back, and it is possibly due to the coarticulatory influence of the adjacent phones.the Thirdly, as shown in the spectrogram of the three tripthongs [iai], [iau] and [uai], the duration of [i] in [iai55], [i] in [tʰiau55] and [u] in [kuai55] are relatively shorter than the rest two vowels in the same syllable, as [ai] in [iai55], [au] in [tʰiau55] and [ai] in [kuai55]. In these CVVV syllables, [u] and [i] are similar to glides or so-called semi-vowels, or approximants [j] and [w] as shown in the spectrogram. Finally, the vowel system in Yang (1957) is more suitable for accounting for the data in this study. Hopefully, the vowel formant data presented in this study will contribute to the study of vowels in Hakka.