The correct spelling of "lehmberg" is [ˈleɪmbɝɡ]. The first sound is "lay" which is spelled with the letter "l" followed by the diphthong "ay" represented by "e". The second syllable is pronounced with the letter "m" and the vowel sound is represented by the letter "e". The final syllable is pronounced with the letter "b" and the r-controlled vowel "er" represented by the letter "g". Therefore, the correct spelling of "lehmberg" is necessary to correctly pronounce it using IPA phonetic transcription.