Audio Interface Shootout: Three Sub $300 Boxes Tested With Real Sessions

By sapi_44530a · · 6 min read

Three interfaces, three different sessions, one deadline. I tracked a fingerpicked acoustic, DI’d a bass through an amp sim, and cut scratch vocals on a dynamic mic, all with boxes that cost less than a decent pedalboard. Here’s what actually mattered.

The sub-$300 bracket is where most home studios live, and it’s gotten genuinely good. Focusrite’s 4th Gen Scarlett line and Audient’s EVO series have pushed preamp quality and converter specs up while keeping prices flat. I wanted to know which one survives a real session, not a spec sheet.

The three boxes

I ran the Focusrite Scarlett 2i2 4th Gen (around $190), the Audient EVO 4 (around $130), and the SSL 2+ MkII (around $350, so it’s the ceiling of this test). The SSL is technically over the line, but it sits right at the edge of “affordable” and I wanted a reference point for what a step up actually buys you.

Quick spec reality check. The 2i2 4th Gen gives you two preamps with 69dB of gain, Hi-Z instrument inputs on both channels, 24-bit/192kHz, USB-C, bus-powered. The EVO 4 is 24-bit/96kHz, two preamps, USB-C, bus-powered, with Smartgain and a loopback feature built for streaming. The SSL 2+ MkII steps up to four outputs and adds the Legacy 4K preamp character mode.

Session one: acoustic guitar and vocal

This is the test that separates interfaces, because a fingerpicked acoustic exposes every bit of preamp noise and converter glare.

The Scarlett’s Air mode is the thing people talk about, and for good reason. It adds a high-frequency lift inspired by Focusrite’s ISA preamps. On a dreadnought mic’d at the 12th fret, Air gave the track a presence that made the raw take sit forward in the mix. It’s not a magic trick, but it’s useful. Push it on a bright condenser and you’ll want to dial it back.

69dB of gain matters more than Air for anyone using a dynamic mic. That’s a real upgrade over older budget interfaces that choked on an SM7B. My scratch vocal on a dynamic came up clean without cranking the gain into hiss territory.

The SSL 2+ MkII is the honest one here. No air mode, no coloration unless you engage Legacy 4K. Clean, detailed preamps. The 4K mode adds harmonic content that flatters vocals in a way that’s hard to describe without hearing it, but it’s subtle. If you want a flat, truthful capture, this is it. If you want help, the Scarlett gives you more rope.

The EVO 4 punched above its price. Audient borrowed preamp technology from their higher-end consoles, and you can hear it. It’s not as quiet as the SSL, but at $130 it embarrasses interfaces that cost twice as much from five years ago.

Session two: DI bass through an amp sim

Here’s where Hi-Z inputs and driver stability earn their keep.

Both Scarlett inputs are Hi-Z, front panel, which is the correct design. If you’ve ever owned an interface with the instrument input buried on the back, you know the pain. Passive bass pickups need a proper high-impedance input or you lose tone before it ever hits your DAW.

I ran my P-bass into each interface, then into a DI amp sim in my DAW. Latency is the make-or-break factor. At 48kHz with a 128-sample buffer, the Scarlett and the SSL both felt immediate. Playable, no perceptible delay.

The EVO 4 capped at 96kHz, which is fine. You don’t need 192kHz for rock or metal, and honestly most people record at 24-bit/48kHz anyway. Higher rates eat disk space and CPU for gains you’ll never hear on a bass track.

Driver stability is the unsexy spec nobody advertises. Focusrite and SSL both ship solid, maintained drivers on Windows and Mac. On macOS, Core Audio handles a lot of this natively, so latency is generally lower out of the box. On Windows, you live or die by the ASIO driver. All three held up over a three-hour session without a dropout. That’s the bar.

Session three: podcast and streaming workflow

I do a weekly two-person show, so I tested these as podcast interfaces too.

The EVO 4 has a genuine advantage here: Smartgain. You hit the button, it listens to your room, and it sets input levels automatically. For a beginner still learning gain staging, this removes the most common source of bad recordings. It also has loopback, which lets you route computer audio back into a stream without a virtual cable hack. If you’re podcasting or streaming, that’s a feature you’ll actually use.

Two inputs is the sweet spot for a solo host or a host plus one guest. If you’re recording a full band or a drum kit, none of these will do. You need four inputs minimum for a small band, and eight or more for a miked kit or a live session. Don’t buy a 2-input box expecting to grow into a drum room.

The specs that actually changed my mind

Ignore the marketing sheet. Four things decided it for me.

  • Preamp gain. 69dB on the Focusrite is the number that lets you run a dynamic mic without a Cloudlifter. That’s real money saved.
  • Hi-Z placement. Front panel or nothing. Both Scarlett inputs are Hi-Z, which is generous at this price.
  • Output count. The SSL 2+ MkII gives you four outputs, so you can run a separate headphone mix or send to outboard. Two-input boxes with two outputs box you in.
  • Smart features. Smartgain and loopback on the EVO 4 are the kind of thing that saves you ten minutes every single session.

Build quality is the quiet factor. All three feel solid. The SSL has the most substantial knobs, the Scarlett is the most familiar layout, and the EVO 4’s single-knob design is either brilliant or maddening depending on your patience.

Which one I’d actually buy

For most people reading this, the Scarlett 2i2 4th Gen is the answer, and not because it’s the most popular. It’s the best balance of preamp gain, Hi-Z flexibility, converter quality, and price. Air mode is a real tool. It’s around $190 and it does the job for guitar, vocals, and DI bass simultaneously.

Buy the EVO 4 if you’re streaming or podcasting and want Smartgain and loopback at $130. The preamps punch above the price.

Buy the SSL 2+ MkII only if you specifically want clean console-style preamps, four outputs, and the Legacy 4K character. At $350, you’re paying for a sound, not a feature list. If you don’t know whether you want that sound, save the money.

The one thing I’d tell anyone: this tier is worth it. The $200 to $500 range is where preamps, converters, and build quality take a real jump over the cheapest budget boxes. Spending a little more here buys you years of recordings that don’t need to be redone. Your call on which flavor.