Whenever your amplifier isn't set up within immediate reach for quick volume adjustments, the remote-controllable Omnitronic LH-125 volume controller is a great solve.
Omnitronic's VC-11 passive volume controller is a device to control the volume of analogue audio signals. For example, you can use it in your PC setup for your speakers or amplifiers.
The VC-22 is an active volume controller from Omnitronic. It lets you finely adjust the volume of analogue audio signals. It can also be connected to Bluetooth for remote control.