Buy the Audient iD4 MKII if you record one voice and want the cleanest possible channel: a Class-A console preamp at -129 dB(A) EIN and 0.0017% THD+N. Buy the EVO 4 if you need two mic inputs on a tight budget, or if your recordings keep coming back too quiet — Smartgain sets the level for you in one button press. Both cap out at 58 dB of gain, so neither suits a Shure SM7B without a booster.
Audient sells these as two different things to two different people, and the specification sheets agree. The iD4 is the company's engineering on one channel. The EVO is the same company's answer to the fact that most beginner recordings are ruined by gain staging, not by preamp quality.
Smartgain is a real feature, not a beginner crutch
Press the button, talk or play for a few seconds, and the EVO sets the input gain to a sensible level on every channel you have armed. It sounds trivial. It removes the single most common failure in home recording: a take that is either too quiet to use without raising the noise floor, or clipped and unrecoverable.
It is also the feature that makes the EVO good for a guest. Handing someone a microphone and not having to coach them through a level check is worth more in a real session than a decibel of preamp noise. If you record other people occasionally and are the only engineer in the room, weigh it seriously.
What the iD4 gives you instead
Numbers you would expect a tier up. -129 dB(A) equivalent input noise and 0.0017% THD+N at 0 dBu are the figures of a considerably more expensive interface, and the preamp is from the same circuit family as Audient's large-format consoles. It is also a metal box rather than a plastic one, with a proper monitor-control knob you will use every day.
And — oddly, for the one-input box — it has two headphone outputs. So a guest can hear themselves on the iD4; they just cannot be recorded onto their own track. Audient iD4 vs iD14 is the comparison to read if that second recorded channel is what you actually need.
Both Audients, and the box that solves the gain ceiling
Audient iD4 MKII
Top pickAudient · The best-sounding single preamp here
The right box if your mic is a condenser or a hot dynamic and you want the cleanest single channel at this price. If you are buying an SM7B, 58 dB puts you straight back into booster territory.
Why it is here
- -129 dB(A) EIN and 0.0017% THD+N are numbers you would expect a tier up
- The Class A preamp is the same circuit family as Audient's consoles
- Two headphone outputs on a one-input box, which is unusual and useful
What it costs you
- 58 dB is not enough for an SM7B without a booster
- One mic input only
- No onboard DSP or voicing
Audient EVO 4
Audient · Anyone who keeps getting gain-staging wrong
The pick for a second host on a budget, or for anyone whose recordings keep coming back too quiet. Not the pick if your mic is an SM7B, where the gain ceiling forces a booster.
Why it is here
- Smartgain removes the single most common beginner mistake in one button
- Two mic preamps at the price of most one-input boxes
- Genuinely small and bus-powered
What it costs you
- 58 dB again falls short of an SM7B's appetite
- Single encoder for everything means more button-pressing than knob-turning
- Plastic build
Focusrite Scarlett 2i2 (4th Gen)
Focusrite · The most gain per dollar in a two-input box
The default answer for someone buying an SM7B or PodMic: it supplies enough clean gain that you never need a booster, which makes it the cheaper total purchase even when it is not the cheaper box. Look elsewhere only if you need MIDI or four outputs.
Why it is here
- 69 dB is the most gain of any interface at this price, and enough for an SM7B with headroom to spare
- 120 dB dynamic range means the converters are not the weak link
- Two inputs, so a second person does not mean a second purchase
What it costs you
- Air mode is a fixed voicing, not an EQ you can dial
- Plastic-and-metal build feels less solid than the SSL or Audient competition
- No MIDI, which matters if you also play keys
The 58 dB ceiling both of them share
This is the thing to check before anything else. 58 dB is comfortable with a condenser, comfortable with a Shure SM58 at -54.5 dBV/Pa, and workable with a Rode PodMic at -57 dBV/Pa. It is not comfortable with a Shure SM7B at -59.0 dBV/Pa, where you will finish the knob's travel with nothing in reserve and hear the preamp working.
If an SM7B is the microphone you own or want, buy a different interface rather than a booster: a booster plus either of these usually costs more than a box publishing 69 dB, and leaves you with an extra link in the chain. Cloudlifter vs FetHead is what the booster route looks like; best audio interfaces for the Shure SM7B is the alternative.
Which to buy
- One voice, best quality per dollar, a microphone that is not an SM7B: iD4 MKII.
- Two inputs on a budget, or a guest you do not want to level-check: EVO 4.
- Your levels are the problem, not your preamp: EVO 4, and the Smartgain button will pay for the box.
- You own an SM7B: neither — spend the money on published gain instead.
One last framing that helps: the iD4 is a quality purchase and the EVO is a workflow purchase. Both are honest products from the same company, and the mistake is buying the iD4 for a second guest it cannot record, or the EVO expecting measurements Audient never claimed for it. If neither fits, best audio interfaces under $200 is the wider field.