What is the ruling on reciting the Adhan loudly or softly for oneself or a specific gathered group?

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If the Adhan is called for oneself or for a specific group present, it is permissible to alternate between soft and loud recitation, or to vary between loud and soft parts. However, this must not occur during the established time for the Adhan, lest people be deceived by thinking a general call is being made, in which case nothing should be recited loudly.