Value of a preamp?

Other than impedance matching and volume control?

Preamps also provide any gain needed to drive the power amp. This is handy if you have a tape machine, tuner or phono section.

In addition a good preamp will minimize or eliminate colorations caused by interconnect cables. If you've auditioned interconnect cables and heard a difference (for example, one does the highs better) then you know what I'm talking about.

If you get the right preamp, it can have less coloration than any passive system available on this account.

I have my phono stage plugged into my Tortuga Audio LDR attenuator then out from there to my amp.

Very clean and transparent and it`s pretty easy to hear changes made to the system, like swapping cables/interconnects or rolling tubes.

Plays as loud as I would ever want too....Pure as Light 👍

Appreciate the input. Would love to know of someone who is exceptional at upgrading preamps as well as repairs.