I purchased the Sonoma Wire Works’ GuitarJack Model 2 after reviewing it a couple of years ago. The iOS-only interface was leagues above anything else available for mobile devices at the time. Unfortunately it wasn’t compatible with Mac OS or Windows so it was a hefty investment for anyone who only occasionally records with an iOS device. The newer GuitarJack 2 USB ($129 street) is sonically identical to the GuitarJack Model 2 but it adds support for Mac OS, Windows, and Android devices.
Still marketed primarily as a tool for recording guitar and bass, this compact, well-made interface is centered on a high-quality, 24- bit AD/DA converter. It includes a 1/4-inch instrument input, a 1/8-inch stereo microphone/line input and a 1/8-inch headphone output. Identical in size to the GuitarJack Model 2, the 2.25-ounce device measures 2.5 inches by 2.3 inches by 0.6 inches. The interface doesn’t provide phantom power, so if a condenser mic is being used, phantom power must be provided from a separate phantom power supply (such as the Audio-Technica AT8801).
The headphone output is exceptionally high quality, far better than anything I’ve heard built into an iOS device or laptop. Coupled with my MacBook Pro and a pair of BLUE Mo-Fi or Focal Spirit Professional headphones, I’ve spent many a day both working and listening for enjoyment through the GuitarJack 2 USB and it sounds killer.
In addition to listening to music through iTunes and Audirvana Plus, I’ve had success using the GuitarJack 2 USB along with iOS devices running FourTrack, StudioTrack, AmpliTube, DigiTech Stomp Shop, GuitarTone, Garage Band and studio.HD, and a Mac- Book Pro running Logic, Studio One 2, Nuendo and Pro Tools.