Review on ⚡️ Seven Star ST-1000 Step Up/Down Transformer: Convert 220-240V to 110-120V or Vice Versa - 1000 Watts by Richard Sallah

Use it to power an imported 5.1 sound system in the US that only runs on 230v. A warning to anyone planning the same or similar. As far as I know, this transformer only converts voltage, NOT the corresponding wavelength (Hz). The standard wavelength that corresponds to 200-240V is 50Hz used in many European countries and 60Hz at 120V used in the USA. The electronics may or may not handle the Hz difference. Look at the product label or the instructions for use. For example, my sound system states that it can operate in the 50-60Hz range, otherwise I would have audio interference if the product worked at all.