It may be different per model? But someone asked this question in the BT30D Pro thread, and the Fosi rep said;It would be interesting to see how the tone controls affect the freq response measurements. A measurement with them at max and maybe min to see the range.
Another user added this info;For the specs, it's ±12dB for Bass control and ±6dB for Treble control.
I found similar results when testing the in room response of some speakers powered by BT30D (older non-Pro);
Presuming it is the same as BT30D models, it is not ideal IMO. Bluetooth is always on and has priority over RCA. This was confirmed by Fosi rep.I have a question... how is the Bluetooth/RCA Input source switching done?
Yes, I understand what you mean. In fact, our team had a brainstorming session about whether or not to include a mode selector. Ultimately, we concluded that if a customer is looking for an amplifier with Bluetooth connectivity, Bluetooth is likely to be their preferred option for playing music. Therefore, Bluetooth connection should take priority over the RCA connection, and the user shouldn't need to select it. Nonetheless, we understand that many people still prefer having a mode selector. Therefore, we plan to create a new model in the future that will meet this demand.