Difference between tts-1-hd-1106 and tts-1-hd

What is the difference between tts-1-hd-1106 and tts-1-hd?

Is tts-1-hd-1106 just a snapshot from when they released tts for the first time?

Format of the 4 digit number seems to be MMDD.

Is tts-1-hd better than tts-1-hd-1106?

You are correct in your assumptions: tts-1-hd seems to be a “stable model name” that can be pointed to the currently recommended model. There is currently only one named model for it to be directed at, tts-1-hd-1106.

The API being audio only, cannot report the true model name like other endpoints.

We can see when the names were originally created, an interesting insight into internals…

[{'id': 'tts-1',
  'created': '2023-04-19 21:49',
  'object': 'model',
  'owned_by': 'openai-internal'},
 {'id': 'tts-1-hd',
  'created': '2023-11-03 21:13',
  'object': 'model',
  'owned_by': 'system'},
 {'id': 'tts-1-1106',
  'created': '2023-11-03 23:14',
  'object': 'model',
  'owned_by': 'system'},
 {'id': 'tts-1-hd-1106',
  'created': '2023-11-03 23:18',
  'object': 'model',
  'owned_by': 'system'}]

Now the brain teaser: can you detect the quality difference with the HD version? Is it pointed to the same thing? A blind test experiment on the audiophiles who perceive better quality the more they pay? It is hard to discern any difference or compare, since every API call is different-sounding.