The SOS36 ’Micro Amp’ pack contains 11 captures of the legendary MXR Micro Amp in each of the ToneX, NAM Standard and NAM Nano formats. (Full details above.)
 
MXR say the pedal,  'adds a preset amount of gain, using a single control. With a guitar, this lets you boost your signal for lead work, adjust between 2 different guitars with unmatched output (i.e., humbucker to single coils), or it can supply a permanent boost in a long effects chain where signal drop-off is a problem.'
 
Who uses it? The are many but here's a few: Jack White, John Frusciante, Flea, Alex Turner, Joe Satriani, Prince and Beck.
 
And a few words on Tonex boosts:
All of our captures are gain compensated to help you make decisions based on tone and timbre rather than volume. As boosts primarily rely on making things louder, they can be a little underwhelming at first – the different settings are much more subtle than their overdrive/distortion/fuzz counterparts. (As some of them have EQ cuts they can also be rather quiet.)

The secret here is to use the volume control on the Tonex Software to give you the volume rise. When you do this the boost starts to behave as expected and, importantly, the pedals you’re boosting into react as expected. Trust us, it’ll bring a smile to your face! Stacking the pedals correctly is where the magic happens…