Does s1 and s2 refer to speaker1 and speaker2 folders? But they are the same.

[baixf-xyz]

I used the default parameters to synthesize the mixed speech of two people, but found that there are 5 folders, namely mix_clean (utterances only), mix_both (utterances + noise), mix_single (1 utterance + noise), s1, s2. I would like to ask Do s1 and s2 refer to speaker1 and speaker2? But I listened to the audio inside, but they are all from the same speaker.