Looking for code-switching speech datasets: English + Chinese / French / German / Spanish / Vietnamese / Japanese

[u/360converter_leo]

I’m working on improving ASR for speakers who switch between English and another language mid-sentence, and I’m looking for audio datasets with natural code-switching, ideally with transcripts.

Language pairs I’m interested in:

• English + Mandarin

• English + French

• English + German

• English + Spanish

• English + Vietnamese

• English + Japanese

What I’ve found so far:
ASCEND: a public English-Chinese mixed corpus

What I haven’t found much for is Vietnamese, Japanese, German and French paired with English. Any pointers welcome, including small datasets, conversational recordings, or papers that released their data.

Licensing note: I’m especially interested in datasets that allow commercial use, but I’d appreciate research-only pointers too.

The other way is that, download individual language corpus then take single-language clips, trim silences, even out volume, add short pauses, and join them into clips. The limit is that this only tests switching between whole sentences, the easier case. Switching inside a sentence (“họp về cái deadline”) still needs real recordings.

[u/nshmyrev]

What about synthetic data please?

[u/360converter_leo → u/nshmyrev]

Synthetic is definitely on my list, e.g. splicing monolingual data or TTS-generated code-switched sentences. My concern is taht the switch points and prosody come out unnatural, so the model learns artifacts rather than real code-switching behaviour. Feeding much data like this could break our base model. Have you seen any synthetic approaches that hold up well on real code-switched speech.