In this online resource there are hundreds of videos (videocasts) about a great variety of topics among which you’ll find something of interest to you.
From all the available categories, the ones that have caught our attention most are related to:
Aspirated vs. partially voiced: Jam vs. Gem.
Homographs: Bare vs. Bear.
Homophones: Muscle vs. Mussel.
Unvoiced vs. Voiced: Lamb vs. Lamp.
Voiceless vs. Voiced: Safe vs. Save.
They show important details and differences within the words that we normally don’t tend to take into account. Moreover, it’s quite difficult to find teaching materials related to this topic so its appreciated when someone explains it.
Visit : Speaking English Podcast