I’m not sure you can just listen to the Pali sounds and get it right though because of L1 interference/assimilation if you are an English speaker? And also due to perceptual deafness?
Actually, for English speakers, learning Pali aspiration is also a process of unlearning aspiration of initial k, t and p, which are always aspirated in English (Phali language, anyone?). This is in addition to the normal process of learning to “add air” for aspirates.
There are several Pali sounds which are problematic for [non-Indian] English speakers as these are not phonemically distinct in English, such as dental and retroflex t, d. I.e. we have them in English but we think they are the same sound. Studies have shown that English speakers are “perceptually deaf” to this distinction and cannot hear it in word-initial position. This is because the ability to distinguish these sounds closes at about 2 years of age. The most that English speakers can do initially is to hear the drag of the retroflex t/d on the preceding vowel in non-initial position. The jury is out on whether English speakers can ever actually learn to hear the difference between these sounds as adults: sometimes I think I can but I have had a decent amount of spoken Sinhala exposure as well.
So I am agnostic on whether English speakers would benefit from recordings of these sounds at all in the absence of explanatory material, given that we can’t perceptually distinguish certain sound pairs. The kindness thing is just to explain to people about their own deafness. I didn’t know about this when I learned Sanskrit and wasted hours listening to the recordings not knowing why I couldn’t hear a difference…
When I teach this, I get people to LOOK at the mouth of someone saying these sounds IRL: we can’t HEAR the difference, but we can SEE the tongue touch the teeth for dental t, d. So video of sounds is actually much better?
Anyway, sorry to info-dump: I just get really excited about teaching to correct L1 interference, I have a kind of personal interest in accent correction from my days as a translator.
P.S. @Jake there is no such thing as combining m. Not aspirating the aspirates is just plain wrong, not sure why anyone would teach that as it will wreck the meaning of words. Yes it is effort and yes you just have to learn how to do it. From memory, the traditional grammars actually give “effort” as one aspect of aspirated sounds.