The set Raspberry + dac + volumio is a player able to play music from a usb drive, a nas, ramplay, radio and from music sent by the air (airplay or upnp) from a device such Iphone/pad or android or even a computer with windoze etc… You can remote it from any device on the same network with a web browser or a mpd client.
But, this set is to be link to your amplifier and that one to yours speakers. The real interest is the high quality you can obtain from the dac.
If what you want is only sending music to your bluetooth speakers, you don’t need all that : just send it from your device (phone, tablet, computer)
But it’s not the same thing.
And you won’t benefit of volumio high quality…