What is the correct pronunciation of "espontaneidad?"

Question

Primero mi pregunta en español:

¿Cuál es la pronunciación correcta de "espontaneidad"?

Details in English:

I was recently in the process of collecting some audio from Forvo to add to a Memrise course I was making and one of the words I wanted to add was "espontaneidad." As I waited for my computer to pull up the page of audio recordings for this word, I wondered how it would be pronounced and discovered that all three of the Forvo contributors treated the "ei" as a monophthong instead of as a dipthong as I had assumed. I initially thought, Well I'm glad I checked because I hadn't been pronouncing it like that. For some reason, however, I decided to see if WordReference had any audio recording of it and what I found there surprised me a bit because the pronunciation differed ever so slightly. Below you will find links to both the Forvo recordings and the WordReference recordings:

Forvo pronunciations of "espontaneidad"

WordReference entry for "espontaneidad"

(Click on the drop down menu to the right of the WordReference entry to select a pronunciation from Mexico, Spain, or Argentina.)

Do you hear the difference? What's the correct way to pronounce this word? In other words, should I pronounce the “ei” combination like “ay” or like “AY-i"? (Please forgive my lack of sophistication in transcribing sound. I am neither a linguist nor a student of the International Phonetic Alphabet.)

Detalles en español:

Recientemente estaba en el proceso de colectar audio de Forvo para añadir a un curso de Memrise que estaba creando y una de las palabras que quería añadir fue “espontaneidad”. Mientras esperaba mi computadora para mostrarme la página con descargables grabaciones de audio, me preguntaba cómo sería pronunciada y descubrí que cada uno de las tres contribuyentes de Forvo consideró la combinación “ei” como una vocal pura (o monoptongo) en lugar de un diptongo. Inicialmente, pensé que Pues, me alegre que las verifiqué porque no había estado pronunciándola como eso. Por alguna razón, sin embargo, decidí ver si WordReference tenía grabaciones de esta palabra y lo que descubrí allí me sorprendió un poco porque la pronunciación era un poquito diferente. Por debajo encontrarán enlaces a tanto las grabaciones de Forvo como las grabaciones de WordReference:

[Véanse arriba en la sección inglesa.]

(Hagan clic en menú descendente a la derecha de la entrada en WordReference para seleccionar una pronunciación de México, España, o Argentina.)

¿Oyen la diferencia? ¿Cuál es la manera correcta de pronunciar esta palabra? En otras palabras, ¿debería pronunciar la combinación “ei” como “ay” o como “AY-i”? (Perdonen mi falta de sofisticación en transcribir sonido. No soy ni una lingüista ni una estudiante del Alfabeto Fonético Internacional.)

Answer 1

Etymologically, there is a hiatus: /es.pon.ta.ne.i'dad/

That said, in words that have hiatuses where the weak vowel is not also the stressed syllable of the word, there is a strong tendency for speakers to form a diphthong. All speakers may end up doing it, and it may be influenced by dialect, register, rate of speech, etc. This is partly why Spanish never developed a way to indicate such hiatuses (outside of poetry) — they are not consistent and never distinguish words.

So you can freely say /es.pon.ta.ne.i'dad/ or /es.pon.ta.nej'dad/ and it's doubtful speakers will even notice which you chose.

Answer 2

First, let's make sure we're on the same page about E being a strong vowel and I being a weak one, which means that without a written accent, these two vowels together would form one syllable. I think your question implies that you're clear about this but I just wanted to make sure.

I listened to the six pronunciations and I see that some people are a little sloppy with the "ei" syllable. I don't see this as a big deal. In English some people are sloppy with the T in "butter" and some people aren't. Both of these cases have a degree of variation I can live with.

Strictly speaking, the first Forvo pronunciation, that shows a clear distinction between the two vowels in this syllable, is the correct one.

I, for one, as a non-native speaker of Spanish, tend to feel reassured when I hear this degree of variation among native speakers, because it tells me I can relax a bit and afford to be just a bit sloppy here and there from time to time.