Amplifier and Speaker
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Hi, I have a pair of speakers (max power input: 250W, nominal power output: 30W) connected to a class-D amplifier (TDA7492, 2x50W) powered by a 12V 72W power supply. Playing music on this setup is way too loud. I have already tried to place a resistor between the amp and each speaker which actually lowers the volume, but I think this is quiet a waste of energy, isn't it? I want to play music from a raspberry pi later on and I guess it would be better to let the raspberry pi control the volume with a digital potentiometer, instead of controlling it in the music player of the raspberry. So, would a digipot be the answer to my problem? Thanks.
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Hi, I have a pair of speakers (max power input: 250W, nominal power output: 30W) connected to a class-D amplifier (TDA7492, 2x50W) powered by a 12V 72W power supply. Playing music on this setup is way too loud. I have already tried to place a resistor between the amp and each speaker which actually lowers the volume, but I think this is quiet a waste of energy, isn't it? I want to play music from a raspberry pi later on and I guess it would be better to let the raspberry pi control the volume with a digital potentiometer, instead of controlling it in the music player of the raspberry. So, would a digipot be the answer to my problem? Thanks.
If you use an additional digital potentiometer, isn't that the same as placing resistors to the connection, either before or after the amplifier. After all those are typically resistor bridges. So the output level on the Pi would still be the same. I would guess that controlling the volume in the Pi, before D/A converter, would lead to smallest energy consumption needed. Also note that the components in the connections affect the quality of the sound.
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Hi, I have a pair of speakers (max power input: 250W, nominal power output: 30W) connected to a class-D amplifier (TDA7492, 2x50W) powered by a 12V 72W power supply. Playing music on this setup is way too loud. I have already tried to place a resistor between the amp and each speaker which actually lowers the volume, but I think this is quiet a waste of energy, isn't it? I want to play music from a raspberry pi later on and I guess it would be better to let the raspberry pi control the volume with a digital potentiometer, instead of controlling it in the music player of the raspberry. So, would a digipot be the answer to my problem? Thanks.
To control the volume you should lower the input of the amplifier. This is usually provided by the audio source but can be also achieved by using potentiometers (analog or digital controlled). But you can control the Raspberry Pi output volume with the amixer command line utility and the alsamixer graphical utility. See for example Sound configuration on Raspberry Pi with ALSA[^] and amixer(1): mixer for ALSA soundcard driver - Linux man page[^].