The diphthong /au/

[chester_100]

Among English diphthongs, /au/ seems to be the most eccentric one:
This could be illustrated by the words loud,gown and house.
I have heard many speakers pronounce the first vowel of the diphthong in house (i.e. /a/) like the vowel in mat , while many others pronounce the same sound like the vowel in pot.

Which one is generally accepted among English speaker(preferably Americans) ?

[Raymott]

I say /hæʊs/ as do most Australians, or even a more centralised /həʊs/
The British are more likely to say /haʊs/ as traditionally written, though accents vary a lot.
/hoʊs/ is problematic since /oʊ/ is used for the sound of ‘home, ‘bone’ etc. It would be uncommon to hear /hoʊs/.
I’ll let an American answer for Americans!

[Soup]

See the standard English diphthongs chart at Diphthong - Wikipedia, the free encyclopedia