Hi, what i can recommend is an Electro Harmonix LPB2UBE Stereo Preamp(http://www.ehx.com/products/lpb-2ube). I use this one to record and before my crate powerblocki and it adds warmth, definition, tone and – if you want grit! and – it's stereo, which is very important, as the factors are stereo themselves. great pedal, for live AND recording.
i use it as the last in chain when i record directly into my pc! sounds like amp recording!