
In these past few days, I had a chance to check out a pre-release sample unit of the iRig Pro Quattro I/O by IK Multimedia, a 4 in (quattro is four, in Italian) / 2 out portable audio/MIDI interface for iOS, Android and Mac/PC, with standalone functionality.
A Deluxe bundle is also available with custom iRig XY stereo mic capsules and complete accessories (more on this below).
It’s been some years since our iRig Pro DUO review, so let’s see what the newest IK Multimedia compact audio interface has in store for you.
Small enough to fit in the palm of your hand, the iRig Pro Quattro I/O packs in 4 high-quality, low-noise mic preamps with phantom power; Hi-Z and line-level instrument, RCA and TRS inputs; plus XLR balanced, 3.5 mm stereo and headphone outputs; and full MIDI I/O. (through the usual adapter cable).

iRig Pro Quattro I/O works right out of the box with iPhone, iPad (no adapters needed), Android, Mac and PC, but can also serve as a stand-alone AD/DA converter, mic preamp or line mixer, with a built-in limiter and direct monitoring.
iRig Pro Quattro I/O can be USB bus-powered, powered by internal AA batteries (included), external PSU, (included with Deluxe version), or power bank (not included).
“The iRig Pro Quattro I/O might be small but packs a lot in”
Recording, Broadcasting, and Podcasting-Ready
The newest IK Multimedia device can be used in 3 different modes, Stereo, Mono and Multi(channel).
In Stereo mode, iRig Pro Quattro I/O mixes all sources down to stereo for streaming or recording.
Mono mode extends compatibility for streaming to social media. A Loopback feature lets users easily duet with favorite videos, plus iRig Pro Quattro I/O can also keep the device under charge for long streaming sessions, using its power supply unit.
Stereo and Mono modes pre-mix up to 4 audio sources (RCA / 3.5 mm stereo line inputs (+ Loopback), XLR combo inputs and MEMS microphone) down to a stereo or mono track, which can be sent to streaming apps, DSLR cameras or sound systems.
In Multichannel mode, the XLR mic/Hi-Z instrument and mic/line combo jacks or RCA / 3.5 mm stereo line inputs are routed to channels 1 to 4 respectively, giving users 4 channels of audio to send to recording apps such as GarageBand or any DAW.
Generous Software Bundle
As usual with their interfaces, IK Multimedia throws in a generous bundle. Mac/PC users get AmpliTube 5 SE with over 80 essential gear models for guitar and bass, and T-RackS 5 SE with 10 analog-modeled and digital processors. Plus, there’s the choice of 2 additional SE/CE titles. Choose from SampleTank, Miroslav Philharmonik, MODO BASS, MODO DRUM or Syntronik 2.
iPhone/iPad users get over $/€100 of audio production apps including fully-loaded versions of iRig Recorder 3 and MixBox for iPad, a must-have effect and mixing app for pro-sounding audio on the go.

Hands-On Impressions
Design-wise, the iRig Pro Quattro I/O is not a radical departure from the previous IK Multimedia interfaces. It’s still an all-plastic affair, albeit this time with a pleasant smoother, brushed finish.
As I pointed out in the past, there’s nothing wrong with using plastic in this kind of device. It’s highly resistant, light, and it obviously helps in making products more affordable.
The unit looks and feels well-built. The switches and pots are firm and the unit just feels nice when held in my (relatively small) hand.
Looking at it, the iRig Pro Quattro I/O inevitably reminds me of other items previously featured here on ANR, such as the (seemingly missing in action by now) MixerFace 4RB and the popular Zoom H4n Pro and Zoom U44. This is not so surprising – honestly, by today’s standards, there are not many other ways to design a compact and camera-friendly audio device. No need to reinvent the wheel here.
Sweet Perks, Nifty Touches
While testing the iRig Pro Quattro I/O, I particularly appreciated some inspiration-friendly features that make this IK Multimedia device even more useful in various situations and setups.
Standalone
On top of the regular workflow you would expect from a product like this, I enjoyed the fact that is also possible to use the iRig Pro Quattro I/O without any digital host connected: in this case, it acts as a standalone mixer/mic preamp device. Just power it up thru battery, external USB or PSU and use the full set of inputs/outputs.
This is a feature I use a lot with my standard desktop audio interface (a Focusrite Clarett 8Pre X) when I just feel like playing an instrument and composing without having any “screen pressure” on. Also, this is the perfect setup for recording high-quality audio on any DSLR or camcorder.
Built-in Mic
Speaking of composing and inspiration, I love having an in-built microphone on the iRig Pro Quattro I/O. Adapting to the audio world what the famous photographer Chase Jarvis once said, (“the best camera is the one that’s with you”), we could say that when inspiration strikes the best microphone is the one we have at hand.
I enjoy using my smartphone and the iPad to capture sounds and sketches here and there, and studio-quality microphones are obviously hard to beat, but it’s really handy having access to an omnidirectional (MEMS) mic right within the interface.
BTW, if you’re wondering, a MEMS microphone is a modern type of mic that is produced using micro-electromechanical systems processing techniques. MEMS mics are also commonly referred to as microphone chips or silicon microphones and they look like this:

Safety Channels
How many times did you have to throw away a recording because it ended up being badly distorted? I sure had this happening a lot when recording audio both at home and in “unpredictable” environments. The iRig Pro Quattro I/O can help. When in STEREO and MONO mode, DAW inputs 3 and 4 are used as safety channels: this means that it is possible to record the same signal present on DAW input 1 and 2 but reduced by 12dB as a backup in case the sound source gets loud unexpectedly and causes the main channel to distort.

Loopback
Also, I like the fact that IK Multimedia added a Loopback feature. Sometimes I need to pass audio from one application to another, for instance from music/radio streaming platforms to my DAW for sampling and sound-mangling purposes. There are software solutions to accomplish this (such as the brilliant Rogue Amoeba Loopback on Mac), but the hardware option is definitely faster and easier.
With the Loopback function turned on, the audio that is input to the iRig Pro Quattro I/O from your host via USB is returned back to the host thru inputs 1 and 2. It is possible to control the level of the loopback stream with the host volume’s control.

Conclusions
The iRig Pro Quattro I/O might be small but packs a lot in. Whether you are a musician, a podcaster/video maker, or a mobile music warrior, the latest IK Multimedia device can be a great match. With its 24-bit/96 kHz audio resolution, it can be used in any pro and semi-pro context, and I’ve appreciated its no-frills yet sturdy design, the versatile features, and the sweet hardware and software perks.
Small niggles? As it often happens these days, the USB power cable is quite short. Also, it would have been better to have a 6,3 mm headphone out (I can never find adapters when I need them!) and I’ve never been a big fan of MIDI adapter cables, but you can’t have everything.
That said, the iRig Pro Quattro I/O definitely passed my test with flying colors.
If you’re shopping for an “all-terrain”, compact 4 in/2 out audio interface (with MIDI I/O) I would recommend adding the iRig Pro Quattro I/O to your list. If money is not an issue, also consider the upcoming Deluxe bundle, it might be worth the extra dough.

Pricing and Availability
iRig Pro Quattro I/O is shipping now and available from the IK Multimedia online store and from IK authorized dealers worldwide. iRig Pro Quattro I/O Deluxe is available for preorder with units expected at the end of June.
iRig Pro Quattro I/O $/€ 349.99* – Includes USB and Lighting cables, batteries, ¼” thread camera adapter.
iRig Pro Quattro I/O Deluxe $/€ 449.99* – Adds 2 x iRig MIC XY stereo microphones, iRig MIC XY windscreen, carrying case, 9V power supply unit.
*All pricing excluding taxes.
For more information about iRig Pro Quattro I/O or to see it in action, please visit:
www.ikmultimedia.com/irigproquattroio
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