product types: 

• preamps
• solid state amplifiers
• tube amplifiers
• EQ effects
• chorus effects
• compression and sustain effects
• delay effects
• distortion effects
• flanger effects
• fuzz effects
• loop and sampler effects
• multieffects
• octave and pitch effects
• phase shifter effects
• tremolo and vibrato effects
• volume and expression effects
• wah and filter effects
• electric guitars