How are the palatal approximant and palatalization different in Slavic languages?

Question

Russians seem to feel (e.g. the answers and comments to this question or this question or this one) that there is a large difference between sounds produced via palatalization (via interaction with soft vowels or the soft sign ь) and sounds produced via iotation (via interaction with the letter й, the palatal approximant).

However, whenever I try to pronounce the two, I am unable to distinguish them.

Question: Can someone link to an audio recording which makes the distinction between them clear? I.e. how is palatalization supposed to be phonetically different from the effects of the palatal approximant?

How are the sounds produced by the palatal approximant and palatalization different in Slavic languages?

For example, compare лён and почтальон. According to the IPA writing, the former's "o" sound is supposed to be only palatalized but not iotated [lʲɵn], while the latter's (final) "o" sound is both palatalized and iotated [lʲjɵn]. But for the life of me I can't hear the difference.

While a link to an audio recording would be preferred, a detailed description of how the position of one's mouth differs between the two would also be very helpful. That being said, it would probably have to be very detailed, because using the descriptions I have already found, I have not been able to create a perceptible difference.

Note: This might be a duplicate of a previous question, but I don't understand the previous question enough to be sure. In particular, I only know that palatalization = "soft vowels" and palatal approximant = "y-sound in English". The other terms I am trying to pick up as I go, but I have very little experience with all of them and am not confident that I understand any of them correctly.

If nothing else, consider this question to be specific to Slavic languages only (or Russian in particular), and the previous question to be general to all languages.

Answer 1

An old question, but perhaps the answer might still be useful.

First, I believe that regarding Slavic languages, iotation is considered a feature of vowels (iotated vowels are preceded by [j]), while palatalisation is a feature of consonants (during their articulation, the tongue is raised towards the speaker's hard palate). Of course, the terminology may vary.

Regarding their interaction in Russian orthography,

• я, е, ё, ю are the iotated variants of а, э, о, у; unless following a consonant, they are preceeded by [j] in pronunciation (compare the archaic Russian pronoun аз [as] with its modern equivalent я [ja]. The letter и is slightly unusual; it is not iotated in isolation, so иметь represents [ɪˈmʲetʲ], not [jɪˈmʲetʲ], but it does palatalise preceeding consonants.
• palatalisation of consonants is represented by ь, e.g. т [t] × ть [tʲ]. However, when a iotated vowel follows, the consonant is palatalised while the vowel loses iotation, hence лён [lʲɵn].
• to represent palatalised consonants followed by iotated vowels, ь is inserted to break apart, so to speak, the interaction described in the previous point. Thus we have [lʲjɵn] in почтальон or [svʲɪˈnʲja] for свинья, which might be less confusing as it contains the iotated я instead of the “plain” о.

Now, regarding actual pronunciation, I believe that the recordings you linked to do actually make the distinction you are asking about.

In почтальон, the speaker would

1. pronounce the л as a palatalised lateral approximant [lʲ], i.e. with the tip of his tongue on the alveolar ridge and with the tongue itself slighty curved upwards, so the blade of the tongue is closer to his hard palate. He would then
2. detach the tip from the alveolar ridge and move the body of his tongue even closer to the hard palate to articulate the approximant [j], before
3. moving on to the vowel [ɵ].

On the other hand, pronouncing лён, he would articulate the palatalised [lʲ] as before, but then directly detach the tongue from the ridge and move it back to articulate [ɵ], i.e. he would omit step two.

I'd say that the difference is audible in the recordings in the Wiktionary entries. Actually, the sequence (palatalised consonant) + (iotated vowel) might be heard even more clearly in the recording of свинья. I may later try to record myself carefully pronouncing the discussed sequences, but I don't really have a lot of experience with audio recording, so it may come out terribly.