What is the best harmonica effects pedal?

There  are very few effects pedals made just for harmonicas. However, the Kinubi PSV pedal has been specifically designed around the frequencies of a harmonica and includes a variety of different effects in one neat unit. e.g.:- Tone, Reverb, Delay, Compression, Bass Boost and Chicago Blues effect (Scorch™).

What is the best harmonica reverb pedal?

There are several to choose from, but most are not made specifically for the harmonica. The Kinubi PSV™ offers reverb as part of an integrated system of effects in one piece of kit. 

How do you overdrive a harmonica? 

Normally you need a pre-amp or gain control, but now you can achieve this effect with the Kinubi PSV Scorch™ control.  According to your harmonica playing technique, this effect gives you the opportunity to create your overdriven Chicago Blues sound.

How do you prevent harmonica feedback?

There are specific individual pedals available to help reduce this very real problem. The Kinubi PSV™ harmonica effects pedal offers a built-in ground lift option which eliminates residual feedback without the need for an amplifier. PSV™ can be used with a battery pack which further reduces the hum at source and makes it an ideal addition to your gig bag.