Hotone produce a wide range of mini FX pedals with all the controls you'll need, good quality, True Bypass and really affordable price.
This is the Thunder Bass unit and it is a 5W Class A/B mini head that delivers true SVT type of sound. With the Hotone NanoCab it makes for an excellent practice amp with a classic sound, but connect a full size cab (even a 4x10") and you won't believe your ears. You can even crank up the volume (it is just 5W after all) and get the full roar of a tube amp at full tilt.