I now have four RPi-based RoPiee endpoints and they are the best thing I have implemented for my music around the home!
I was wondering what the typical power consumption would be based on them running on an RPi 4B. Is there such a thing as standby or low power mode?
Not sure about power consumption, but could test with a (smart) outlet, such as Eve Energy.
Raspberry Pi does not, as far as I know, any power management, such as standby mode. It’s either on or off (no power). There are hardware (HATs) that could do this, but probably not a good solution, as Ropieee don’t support it - and you want other HATs.
ropiee running on RPi2 + pi 7" display + DigiAMP hat is sucking 3,4W at idle (display is on with clock) and about 5W when playing music in small room on 87dB speakers, even quite loud
measured by aeotec smart socket, not sure how precise it is though…
My guess is that RPi4 will be around 7W at idle.
You can reduce power consumption by downlocking cpu, memory and adequately lowering voltages and on rpi3/4 by disabling bt+wifi in boot config if not needed. This is for advanced users only, not supported by ropiee web gui of course 
I have some ideas for this, so it’s ‘on the list’ for NG.
Does someone know if this hack to lower power consumption on idle is compatible with Ropiee on a Raspberry Pie 4B? Will it still be visible and able to wake up as a Roon endpoint? - How To Reduce Raspberry Pi 5, 4 Standby Power Consumption | Tom's Hardware
You should edit the configuration file but it’s not possible in RoPieee (maybe for now) that should be considered as an appliance (get it as is)
Yes, I would likely be able to find my way to configuration file, but I’m new to this. Maybe, it’s baked in to Ropieee in a way that attempting to change it does not make sense. @spockfish, maybe you have a comment before I consider trying it out?