Here's what Zoom say about the A1 Four:
With specially engineered effects, built-in looper and drum machine, the A1/A1X FOUR is the first Multi-Effects Processor designed for a variety of acoustic string and wind instruments.
Add a multitude of warm and rich tones to your guitar. From live “unplugged” performance sounds to the finger-playing style of country and blues, there’s so much to choose from. Gorgeous effects and acoustic guitar modeling will take your instrument to places it’s never been before.
The A1/A1X FOUR is preloaded with over 80 effects, including more than 35 new groundbreaking effects designed and engineered for acoustic instruments.
Add depth and dimension with acoustic emulators and modeling. Refresh your instrument’s natural sound, allowing your live performances to sound just like your studio recordings. Select and hone in on the tone of your favorite guitar make and style.
Acoustic Guitar Modeling
The A1/A1X FOUR make it easier than ever to process the sound of your own Acoustic Guitar. With a selection of 15 factory presets (plus13 more available as free download on Guitar Lab), you can select your favorite AG MODEL, D-28 for example, and recover instantly the sound character of that renowned and original body shape.
IR (Impulse Response) technology is used to capture the sonic fingerprint all guitar shapes and bodies available on the A1/A1X FOUR and via Guitar Lab. Each AG MODEL can be adjusted with 4 parameters (Gain, Bass, Mid, Treble) to control the volume and refine the audio output of your modeled sound.
In Patches you can also set the AG Pickup Selector (AG PU SEL) to match your guitar’s pickup type (Piezo or Magnetic) and add a specific EQ modeled on a variety of dedicated processors.