I am a native speaker of English from the US. I recently discovered that what I thought to be perfectly normal for me may not be the norm for everyone. Upon analysis, I have come to realize that when I pronounce a word with /n/ followed by (unvoiced) /s/, I sneakily and ever so slightly insert /t/ between the two sounds.

Thus, 'prince' and 'prints' sound alike when I say them.
So do 'attendance' and 'attendants'.
And ‘patience’ and ‘patients’.
Likewise, 'Mount Saint Helen' and announcement have the same sound.

Other examples of my speech:
insurance, nuisance, intelligence, ounce, rinse,

I have tried to say the words of the questionable /t/ without that additional sounding, trying to glide from the /n/ to the /s/, but I find it totally unnatural.

Dictionaries do not include /t/ in their pronunciation guides of the words 'prince' or 'announce', but then they do not use the International Phonetic Alphabet as their indicators.

Nobody has ever "caught" me on this: I'm the one who brought up the idea that 'prints' and 'prince' are pronounced the same. My question! Is this a peculiarity of mine only (apparently unnoticed by others) or a phenomenon that exists in general and is so covert that most people don't recognize it? Remember: my /t/ slips in ever so lightly; it not a strong sound, but I hear it and I feel it as well.

I'm hoping for answers from those with at least some study of linguistics, although others may find it interesting to say the words while paying close attention. And, if you speak from some authority (degree or study in linguistics, I'd appreciate knowing that).
Hi Philip, welcome to the forum.
The pronounciation of "prince" and "prints" are so similar, as you said, the "t" sound you pronounce is very weak. And considering the redundancy in everyone's speach (it is about %70 in my language, I don't think that it would be less than %50 in English), you can figure out why nibody has mentioned that to you. I mean that they have not noticed it because they do not need to hear that particular "t" to distinguish which one you are uttering, it is so obvious from the context, and they hear it as the same phonetic pattern that they expect, unless they are linguistics who want to transcript your speach.
And every change in a language starts from somewhere. As long as you are the only, or one of the few people who pronounce it in a specific way different from the norm, there won't be a language change. However, as soon as it gets common, we can say that a change is taking place. And as you know, dictionaries record the pronounciation of the majority, not the individuals. It doesn't matter if it uses the IPA or another system.
The reason why you are pronouncing it this way is unclear, just wanna mention that this sound exists in the phonemic system of some languages, for example German.
BTW, I hold a degree in linguistics, though I am not a linguist.
Good luck,
The /t/ in question (between /n/ and /s/) is but one of many "sycophant consonants" which occur naturally because of the way we must make transitions between consonants with certain movements of mouth, tongue, lips, etc. Dictionaries usually transcribe something fairly close to phonemes, not phones, so these will not normally appear in them -- not even necessarily if IPA is used, unless it is a very tight transcription.

The transitions which are most likely to generate sycophants are from nasals to fricatives. The sycophants are all plosives. The first three are the unvoiced series, the next three the voiced. In the voiced series it seems easier to emphasize or de-emphasize the sycophant at will (for some anyway). The phenomenon is more common in the unvoiced series. In many cases, the articulatory organs simply pass so quickly through the position which forms the sycophant that the associated sound is barely heard, if at all.

This phenomenon is common to all languages. It is related to movements of the tongue and lips necessary for consonant transitions in any language, and not to the characteristics of any specific language.

Nasal...Sycophant Fricative
...m.........p............ f, th, s, sh
...n..........t............. th, s, sh
...ng........k.............th, s, sh
...n..........d.............z, zh

Note that English orthography sometimes shows the sycophant, sometimes doesn't.

mpth: warmth (sycophant 'p' not written)
mps: glimpse (sycophant 'p' is written)
mpsh: New Hampshire, redemption (sycophant 'p' written)
ntth: tenth (sycophant 't' not written)
nts: pence, fence, ounce, answer, Linz, ... (sycophant 't' not written)
nts: pants, amounts, ... ('t' written)
ntsh: tension ('t' not written)
ntsh: inch, pinch, ... ('t' incorporated within the "ch" = "t" + "sh", so 'indirectly' written)
ngkth: length, strength ('k' not written)
ngks: linx, manx ('k' incorporated within the "x" = "k" + "s", so indirectly written)
ngksh: anxious (as above)
mbz: lambs (sycophant 'b' is written)
ndz: lends, bends ('d' written)
ndz: lens, Ben's ('d' not written)
ndzh: injure, danger, engine ('d' incorporated within the "j" or "g" = "d" + "zh" )
nggz: rings, sings, ... ('g' not written, or rather, the written 'g' serves a double purpose: to velarize the 'n' to 'ng' and then as a barely heard sycophant connecting to the 'z')

I cannot hear, nor easily produce, any difference between "prince" and "prints". I don't believe anyone else can either! However, the voiced counterpart is troublesome: I can almost convince myself that there is a difference between "bends" and "Ben's", although I think in speech at normal speed (not too careful about pronunciation), they are the same.

Students: We have free audio pronunciation exercises.
"Some day my prints will come", as a friend of mine said, when the lab lost his holiday snaps.

I find a tiny difference between 'prints' and 'prince'. In the latter, the /t/ sound is more or less a glottal stop; in the former, the tongue just touches the teeth.

(Maybe BrE is more glottal generally.)

Sometimes I hear 'ung-yen' for 'onion'. Is that a related phenomenon?

Thanks, Cali. In the case of 'injure', etc., I think the sound is, actually "d+zh" and has nothing to do with the preceding 'n'. 'Judge', for example.

I had an explanation from a separate message board that I'll share with y'all.

Voiceless stop insertion (English): Between a nasal consonant (n,m,ng) and a voiceless fricative (s,f,th,sh), a voiceless stop with the same place of articulation as the nasal (p,t,k) is inserted.

From: Language Files, eds. Stewart & Vaillette

So this means that:
Dance /dans/ --> [dants]
hamster /hamstr/-->[hampster]
lance /lans/ --> [lants]
strength /strength/ -->[strengkth] (I only sometimes add the k..I had to try it a few time before I had a natural sound. In my accent I delete the ng sound altogether and say [strentth]
In the case of 'injure', etc., I think the sound is, actually "d+zh" and has nothing to do with the preceding 'n'. 'Judge', for example.

I think one of the sound values of "j" or "ge" is, and was historically much more so, "zh". That's why the "d" was added in such words as "ledge". Without it, the sound (back then, historically) would have been "lezh". A similar phenomenon, also related to French, is the insertion of the "t" before what used to be the "sh" sound, spelled "ch": "catch". Without the "t", it would have been a rhyme with "cache".

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Hi CJ,
I'm not sure about the history of those sounds, wheather they were pronounced as "lezh" and "cache" or not. However, there is another explenation why these sounds are usually displayed with those spellings. As you know, both "dzh" as in "injury" and "tsh" (I do not have an IPA-enabled keyboard)or "tch" as in "match" and your example are stop fricatives, a combination of the stops "d" and "t" and fricatives "zh" and "sh". If you pronounce the stop-fricative sequence, it would give you something very similar to our stop-fricatives. In the IPA system they also just combine the stops and fricatives signs to show the stop-fricatives. I think that's why they are written in this way in our texts. (In German, "sch" is prounced as "sh" in English, and "tsch" as "ch")