I understand this is a combinations of a few ending particles, but I've seen
it enough times that I wonder what general feeling a native gets from it.

Examples I remember:

> 終わったんだよなぁ。  
>  難しいんだよなぁ。
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2015-10-11T04:22:48.697
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2015-10-11T15:34:51.073
2015-10-11T15:34:51.073
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particles sentence-final-particles
~んだよなぁ What general meaning/feeling does this give?
It sounds as if the speaker is feeling reluctant to admit it. That said, it's
not so much the meaning of よ or な/ね themselves as the sentence being prolonged
by somewhat easily linkable particles.
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2015-10-11T10:12:19.047
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2015-10-11T10:12:19.047
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I think we use 「～～んだよなぁ」 most often when we:

  1. Draw a conclusion or confirm something in a calm but somewhat exclamatory manner 

or

  2. Remind someone (or often oneself) of something.
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2015-10-11T11:51:40.340
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2015-10-11T11:51:40.340
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answer