I am considering buying a booster pedal. I want it to be as clean as possible, don’t want it to add any “character”, etc. I just want to raise the signal level at the start of the chain (right after the tuner).
I’ve looked at the below four, any opinions on these? Positive/negative experiences? (My pick would be the tc Spark Mini.)
Check on Basstheworld I know Gregor has reviewed a few esp for clean signal.
What I would suggest, instead of a booster, find a compressor that has an output gain and put that first in your chain. Many compressors do.
Compressors can usually offer a really nice clean boost, and you’ll want a compressor anyway. It will probably always be on anyway, and even if you don’t have it compressing, it can still offer the boost. This saves a pedal space.
I have the full fat Spark, not the mini, and it’s a brilliant, versatile pedal - I’d quite like another one in the same chain actually. It does a perfect clean boost, but also can add some nice mild gain and a mid-boost if needed. Well worth the slightly higher cost over the Mini.
Already tried that (I have a Darkglass Hyper Luminal), but even at full output level the clean tone is still not loud enough. I can raise it further by EQ’ing the shit out of it and adding cab sim later in the chain (in the Element), but I’m trying to make my clean tone loud enough for recording.
What is the input level in the DAW now?
Ideal is about -12dB to -8dB, which can actually sound rather quiet. You then increase the level in the DAW. This might simply be your audio interface working as intended.
Also what kind of bass are you playing? I think booster is typical for passive basses.
I was actually trying to find exactly that a minute ago, so that I can include that information in my previous reply. 
But as far as I can tell Garagaband does not display the input level in a numerical format anywhere, so I have no idea. What I see is that my input level is a couple of bars below the yellow line.
To give a bit more background on what I am trying to do here: I recently bought a Darkglass Element, which I am really trying to like, but at the moment it’s just not usable as a DAI.
My previous setup looked like this: passive bass → pedalboard (tuner, compressor, Big Muff) → Rumble → Scarlett → MacBook → GarageBand. With this setup I was able to raise the level to anywhere I wanted by using the knobs on the amp and the input level knob on the Scarlett.
My new setup is: passive bass → pedalboard (tuner, compressor, Big Muff, Element) → MacBook → GarageBand. By removing the amp and the Scarlett from the chain everything is a lot simpler, but I’ve lost my two places where I was able to raise the signal level. The Element unfortunately does not have an input level setting. It has a three-way switch on the side, but it only does attenuation, and it’s already in the 0 dB setting.
Yes, passive basses (2 passive Laklands, plus an active/passive Ibanez that I only use in passive mode)
In the Element you can turn on the power amp section in the signal chain to boost your signal. This is a clean channel (just turn off drive, presence, etc. but boost the level).
I actually have a support case open with Darkglass, because the presence setting on the amp sim makes no difference at all. It seems to be stuck in a maxed out value or something, and the moment I turn on the amp sim everything immediately sounds like shit.
Well that shouldn’t be the case. 
It’s a PA without a preamp so it really shouldn’t affect your sound. You can shape the tone by drive and presence but if you keep those at 0 it should just boost your signal. Resonance is not needed either. Seems your Element is the culprit (might need a factory reset or something).
Did you check your EQ setting? Also I didn’t had any problems with it either on passive and active basses. Think I even did an input check for Eric once to test the signal (was fine for me).
Wish Darkglass would just release a HX Native type of plugin… Also keep note that the record quality of the Scarlett is usually higher compared to other devices where the DAI is not the main functionality of the device.
Below is the video that I sent them. It was made with cab sim off and EQ off, only the amp sim was on.
Their official stance on the matter is (direct quote): “This is pretty weird” 
LOL. Yeah it really is since it has to be software related. Hope you get it sorted or a new unit since it seems your Element is the culprit.
Fully agree with this. The Hyper Luminal has an excellent output feature. Pretty sure if you skip the Element that the signal would be fine into your Scarlett?
Everything has been working fine with the Scarlett (with and without compressor), but the idea here is to use the Element as the DAI and get rid of the Scarlett