If you have completely moved to digital souyrces, a DAC with volume control is a modern day preamp. I use an RME ADI-2 DAC for that, and it also has many of the traditional virtues of a preamp like balance and tone control, fliters, plus a lot extra.
Traditional preamps served to switch between sources of very different output voltage, so they had to include some source specific amplification. Not so with digital sources. They only need digital to analogue conversion. So inserting a traditional preamp between a properly gain matched good DAC and a power amp is a complete waste of money, and can only degrade the sound