I've got a Fender LP with Pegasus/Sentient pickups and Focusrite Scarlett 2i4 (new gen with the pads) which I use for DI recording as is. I've been trying to figure out how to properly set the input levels on the interface for a while now. The general advice I found was to set the pickup knobs on the guitar to max always, select either of the two pick ups (since one is slightly closer to the strings than the other), and for that pickup play as loud as physically possible, enable the pad (should I use it even when my signal doesn't go red with no pad?), and adjust the interface preamp volume RIGHT under the point where it gets red/yellow for the loudest possible thing I could play, right before it starts to clip. 

This from what I read is to increase the "head room", and make sure the PC gets as much signal/noise ratio as possible before clipping starts. Also, the louder the interface's preamp is, the more "details" from the sound are amplified and received by the interface. Is this the correct approach? With distorted rhythm presets (which I usually get through VSTs like Guitar Rig, Legion/Poulin amps+impulses etc) the sound seems fine, but with clean recordings, when processed through VSTs etc they sound oddly loud, with very small "increments" in the volume adjustment, like there is a very small volume difference between the loudest and quietest parts of the sound, is over-compressed the term? It still sounds fine if I just use non-amp VST FX on the raw signal, albeit still a bit loud and aggressive, with low "sound contrast", sounding "loud" even with the volume set to barely audible.

Also, recording high gain non-chord strummed parts (what Melodyne classifies as "polyphonic", like the intro to Slipknot's Dead Memories or FF's Feast and the Famine) with the aforementioned way of setting the input volume sounds ugly AF, and leads to crackling and hissing during the riffs. I am aware of the mains hum, that just goes away when I touch the guitar, but I feel like there is some noise that I can't hear at all in the raw, clean part, but high distortion amplifies it. At its worst, it covers up the actual melody being played with shshshsh at very high gains, causes some notes to become inaudible mid-riff etc. Is that caused by setting the 2i4's preamp too high, or a more general guitar problem, like badly shielded pickups or something? Playing with the gain levels on the VSTs didn't do much, the sound went from too low-distortion for the tone I wanted, to immediately having the hiss within 2-3 increments. 

I understand that DI won't ever get you the same quality as a mic with an amp, you'll never be able to replace that missing air, I get that, but what is considered the "standard" way to set the input levels on the guitar and interface, and actually DI record with just an interface and a guitar? 
Sorry for the long question, been looking for solutions on forums for a while but no one seems to have the same situation as me, as most people prefer to mic amps (which is a method with far superior quality, but unfortunately not an option for me atm). I understand if this gets a low response rate, I really rambled on here.
Last edited by Pkmm at Apr 23, 2017,
From what I read, that "just before it clips" approach is not necessary with digital recording, it may even be detrimental. The logic goes that as you apply effects, you'll need more headroom, and having too loud a recording will leave you with subpar sound quality, so it's best to record at -6 or even -12db. Your problem might be due to this, know that you're not really fighting against signal loss when you're recording direct, so you can safely run noise gate etc. To avoid confusion, I'm talking about the input level you adjust in your interface, not your guitar's settings. For that, I'd say it depends. I mostly set the volume knob to max, to get maximum sustain, but sometimes I dial it down as if I'm playing rhythm in a live setting. I don't know the characteristics of your pups, but mine sound too bright in DI, so I usually lower the tone knob a bit. 

Links about recording levels:

I highly recommend you to check other tips&vids there, usually they are short&concise, I went through many in 2x speed (best youtube feature ever) and even though I'm using a different DAW I learned quite a lot.
diemydarling so what can I use with which to adjust the desired volume? Previously it was playing as hard as possible while setting the volume right below the Scarlett's indicator turning yellow. No variation there, you will always set the interface volume the same every time. I assumed that was the "optimum" volume. 
How do I set the volume of the interface without this objective measure? What should I be aiming for, just above barely audible? How do I set my interface volume to "-8 dB" for example?

Also, surprised to hear the "just before it clips" volume adjustment method actually doesn't affect or improve clarity. I had assumed the louder the signal (but not clipping) the more the small variations and small details in the sound are audible, so the loud and quiet parts are all more enhanced, and "more" of the sound is received by the PC. If it's set low, then the PC is dealing with a quiet sound that has to be amplified, and the quiet turns into noise (basically lower signal-to-noise ratio). I'll have to read more about how that's not the case with digital recording. I'll definitely check the links once I'm done with work.

EDIT: from the article:  "Recording as “hot as you could without clipping” was perfectly suitable advice for those recording to through consoles and to tape" OK thanks man looks like my situation is more common than I thought what's happening with my clean guitars is "digital clipping" then?
Last edited by Pkmm at Apr 24, 2017,