It takes a fairly technical discussion about electrical impedances and how signal connections are affected by them.  The short answer is the Redeemer preserves your guitar’s sound no matter what you plug into; you can even plug directly into a PA or recording equipment without a direct box.  For the technical answer, we’ll try to keep it simple, here goes:

Your guitar’s signal is divided across the output impedance of the guitar and the input impedance of the guitar cord combined with whatever it’s plugged into.  Ideally, the output impedance would be zero and the input impedance would be infinite so 100% of the signal gets through.  In reality, a typical guitar’s output impedance might be 10K ohms and a typical cord plus FX pedal‘s input impedance might be 90K ohms… In that case, 10% of the signal would be lost and 90% would make it through.  Suppose the cord plus FX pedal’s input impedance was 1M ohms?  Then only 1% is lost and 99% gets through. 

It gets more complicated though, because impedance is usually frequency dependent, for example the guitar’s output impedance might be 10K ohms at bass frequencies and 20K ohms at treble frequencies.  Likewise, the cord plus FX pedal combination might be 1M ohms at bass frequencies and only 10K ohms at treble frequencies …  in this scenario, you get 99% of the bass signal, but only 33% of  the treble – in other words the tone becomes muffled.

But, what if the guitar’s output impedance was close to zero ohms, or the cord plus FX pedal’s input impedance was nearly infinite?  Think about it, in either case, nearly 100% of the signal can get through.   The Redeemer addresses both.  From the guitar’s point of view, the Redeemer’s input impedance looks extremely high,  over 20M ohms; and from the FX pedal’s point of view the Redeemer’s output impedance looks very low, below 75 ohms…  Therefore, nearly 100% of your signal get’s through at all frequencies.  Even if you plug directly into the line input of PA which is typically 10K ohms, you still get over 99% of your signal – that's better than any direct box!