I think this is as revolutionary to my sound as digital room correction was.
first: you don't necessarily need a SPL meter. you can use it by ear like this:
listen to songs you love on Spotify (with normalization turned on) and put them to "perfect volume" on your amp. this "perfect volume" will be too loud over time, right? attenuate volume in the plugin now, and do so all the time you want it louder or less loud.
now, the SPL meter version works much better if you want to hear references* for mixing and/or mastering and while mixing and/or mastering.
btw: there is no real standard for music as this recent topic on facebook in a group which masters like Bob Katz participate once again showed:
https://www.facebook.com/groups/1458538 ... 638434524/
only real standard is Katz's k-system, which isn't realy widespread in popular music.
the other standard which k-system is based on is for movie-theaters: -20dB RMS pink noise should read 83dB on c-weighted SPL reader for a single speaker (for stereo).
now if you research this you will find a widespread recomendation to lower this 83dB acording to the size of your room, and distance to your speakers. actualy audio engeneering is kind of a pseudo-science; there is no real foundations to most of the things you read.
one thing Katz for sure is right about: you need a fixed reference level; so you get used to the right balance at that level. now with loudness compensation we have the advantage to adjust level without (theoreticly) effect balance.
So what is the right SPL meter level to adjust the amp volume knob for this plug-in? there is no right answer to this. personaly I am trying out pink noise reading -14 LUFS atm, since this is +or- the normalizations standard steaming portals are using.
I recomend researching reference levels for mixing/mastering to develop personal conclusion about this. at the end, the most famous engeniers seam to use all their own levels, so the most important thing is to stick to a fixed level. this would mean: adjust amp volume to what sounds best to you on full volume, and then attenuate using volume knob in plugin (I am realizing I just came back to the "you can use it without SPL meter part lol")
*all music you are hearing at your system should be balanced for this, even in you free time, so that balanced music becomes natural for you while mixing/mastering