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InfluxDB
Power Real-Time Data Analytics at Scale. Get real-time insights from all types of time series data with InfluxDB. Ingest, query, and analyze billions of data points in real-time with unbounded cardinality.
There are also pure software TTS solutions available such as this library that claim to run on a plain Arduino Uno without much external hardware other than perhaps some form of amplifier. I have not used this library myself but it looks interesting.
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