#1
I was wondering is there was a specific pedal I could use to get as close to bass sound as possible? I play a lot with a loop station ya see and don't particularly want to be switching between bass and guitar just for a loop. This is just for bedroom use.

I'm guess an octave, but is it possible to get a 100% octave down?

Many thanks
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#2
It can be a bit difficult to get a realistic sound like that, but since it is for bedroom jamming, sound doesn't matter much. Many octave pedals have balance controls, which is to say that there is are lever controls for dry signal (original) and wet signal (octave). That or any pitch shift pedal that does octaves will work for what you want.
There's no such thing; there never was. Where I am going you cannot follow me now.
#3
Not only possible but more and more common with the recent trend of lower and lower tunings.

What you're looking for will be called something along the lines of a "wet/dry octave down." Wet/Dry refers to the ability to mix the regular ("dry") with the octave down ("wet"). A fully wet mix is the "100% octave down" you're asking for. That might help your search. Most octave pedals these days will have some form of wet/dry control.

The EHX Pitch Fork, for example, has a blend knob, and recent versions of the Digitech Whammy have wet/dry outputs, the Boss OC-3 has separate level controls and output jacks for the wet/dry. Depending on how sophisticated you want to get with the routing, you could use a few other boxes to split and process your signal separately once it's been dropped an octave. This would let you make it sound a bit more bass-like with some EQ and compression, instead of simply lowering the guitar. It all comes down to how committed you are - is this "guitar in a cheap wig" or full-on "primetime drag queen?" Both can be had, depending on how much you care and/or want to spend.

If you use a multi-FX unit like an M13, you'd be able to do all of the above with a single stomp by arranging presets that do it all at once (drop an octave, kill the dry signal, change the EQ to sound more like a bass) and switch back and forth between a regular guitar preset and your faux-bass preset. That's probably the way to go, if you're willing to spend some time editing presets and tweaking.