The iPad, iPhone and iPod touch continue to take an increasingly prominent role for musicians in everything from live performances to studio composition, and iPads are quickly becoming central components in many studio setups because of their portability and ease of use. iOS applications can provide a plethora of recording, mixing and virtual effects applications, often replacing much more expensive physical gear with entirely digital solutions, although high-quality hardware accessories are stil required to interface with actual musical instruments such as guitars.

IK Multimedia’s iRig STOMP ($60) is a stompbox guitar interface designed specifically for iOS users, and designed to easily integrate into a guitar or bass player’s existing pedalboard and rig setup. Made from a durable aluminum-cast enclosure, iRig STOMP provides a 1/4” phono jack for connecting an external guitar or bass, and a mono/stereo 1/4” output jack pair for connecting directly to a guitar amp, P.A. system, or additional in-line pedals. Two 3.5mm jacks on the top of the device provide an external headphone connection and the iOS device interface.
A standard 6.5-foot mini jack cable is included for connecting to the 3.5mm port on an iPad, iPhone or iPod touch. A large gain knob on the front allows quick adjustment for input signal gain with ranges designed for typical active and passive guitar/bass instruments, while a bypass footswitch allows the iOS signal processing to be completely bypassed, simply passing the guitar/bass input directly through to the output jacks. The headphone jack can still be used to preview other audio from the iOS device, even when the main output is bypassed.
iRig STOMP uses an active output circuit that can be powered by an included 9V battery or an optional external 9VDC/0.5A power supply, allowing for a clean system signal with lots of headroom that easily integrates into a variety of amp configurations—particularly useful for working with high-gain amps. The device automatically powers on or off based on whether an instrument is connected, conserving battery when not in use.
Since the iRig STOMP connects directly to the iPad, iPhone or iPod touch headphone port—following most but not all of IK Multimedia’s other accessories—Dock Connector compatibility is not an issue, allowing the STOMP to be used with the iPhone 5, fifth-generation iPod touch and presumably also the iPad mini and new fourth-generation iPad.
IK Multimedia provides its own AmpliTube app for sound and effects processing, however the iRig STOMP can be used with any third-party guitar processing app that uses the iOS mini-jack.
We tested the iRig STOMP connected directly to a Marshall MG101CFX amp on the clean channel, crunch OD1 channel and high-gain OD2 channels. Used with AmpliTube for amp tone modelling on the clean channel, the results were impressive, with good tonal range and crisp sound quality. The iRig STOMP also fulfills its headroom promises, with a virtually distortion-free experience when used with the high-gain OD2 channel, allowing for screaming guitar solos. In comparison to IK Multmedia’s original iRig guitar interface, iRig STOMP produced noticeably better results overall, with dramatically better sound when working in more advanced AmpliTube configurations and at higher volume and gain levels.