Focusrite Clarett 4Pre Review: Specs, Pros and Cons

As an Amazon Associate I earn from qualifying purchases. This write-up is based on Focusrite’s published specifications and documentation, not hands-on testing.

The Focusrite Clarett 4Pre (sold as the Clarett+ 4Pre) is an 18-in/8-out USB-C audio interface with four Clarett+ mic preamps, two JFET instrument inputs, ADAT expansion and converters rated at up to 124 dB dynamic range. It suits home and project studios that track a small band, a drum kit with a few microphones, or several sources at once, and want room to grow.

See the Focusrite Clarett+ 4Pre on Amazon.

Focusrite Clarett+ 4Pre key specs

Total I/O	Up to 18 inputs / 8 outputs (including 8 ADAT inputs)
Mic preamps	4 Clarett+ preamps, +57 dB gain range, −129 dBu EIN
Air mode	All-analogue, with impedance switching, modelled on the ISA preamp character
Instrument inputs	2 high-impedance JFET inputs
Line inputs	4 fixed line inputs plus the variable combo inputs
Outputs	4 balanced line outputs, 2 headphone outputs
Conversion	24-bit/192 kHz; line output dynamic range 124 dB
Digital	ADAT optical input (8 channels)
MIDI	5-pin In and Out
Connection	USB-C; macOS, Windows and iPadOS

Figures are taken from Focusrite’s Clarett+ 4Pre product page.

What the preamp numbers mean

Focusrite lists the mic inputs at 57 dB of gain, an equivalent input noise (EIN) of −129 dBu, a maximum input of +18 dBu and THD+N of −110 dB at +20 dB gain. EIN describes the noise a preamp adds when it has nothing to amplify. A figure around −129 dBu is close to the practical limit for a microphone preamp, so on quiet sources such as acoustic guitar or soft vocals, the room and the microphone’s self-noise will usually be audible long before the preamp is.

The 57 dB gain range is enough for most condenser microphones and for dynamic microphones on loud sources like snare, guitar cabinets and sung vocals. Very low-output dynamic and ribbon microphones on quiet speech can still sit near the top of that range. If you plan to record whispered voice-over with a low-sensitivity broadcast dynamic, check that microphone’s sensitivity against the 57 dB figure, or budget for an inline booster.

The +18 dBu maximum input on the mic channels and +26 dBu on the variable line inputs matter when you feed hot sources. Synths, drum machines and outboard gear with +4 dBu nominal levels will not clip the line inputs at sensible settings.

Air mode explained

Air is an analogue circuit on each preamp. Focusrite describes it as recreating the effect of its ISA preamps by changing the input impedance and adding presence. In practice, Air lifts the upper frequencies before conversion, which can help a dull microphone or a dark room. Because it happens before the converter, it is printed into the recording; you cannot remove it later the way you can bypass an EQ plugin.

A sensible approach is to record a short test with Air on and off, at matched levels, and compare. Bright condenser microphones on sibilant singers often sound better with Air off, while dynamic microphones on vocals or guitar cabinets may benefit from the lift.

Inputs and outputs in a real session

The four combo inputs give you four preamps. Two of those inputs switch to JFET instrument mode for guitar and bass. On top of that, four fixed line inputs take keyboards or outboard returns, and the ADAT optical port adds eight more channels at 44.1 or 48 kHz when you connect an ADAT preamp such as Focusrite’s Clarett+ OctoPre. That is how the interface reaches its 18-input total.

Session	How the 4Pre covers it
Singer-songwriter: vocal + acoustic guitar	2 preamps, with 2 spare for a stereo guitar pair
Four-piece drum setup (kick, snare, 2 overheads)	All 4 preamps
Full drum kit with 8+ microphones	4 preamps + 8 ADAT channels from an external preamp
Keyboard rig with two stereo synths	4 fixed line inputs
Two-host podcast with separate headphone mixes	2 preamps + 2 headphone outputs

The four balanced outputs let you run a main pair of monitors plus a second pair, or send a line out to outboard processing. The two headphone outputs each get their own level control, which helps when an artist and an engineer need different volumes.

Conversion and monitoring

Focusrite uses independent A-D and D-A converters and rates the line outputs at 124 dB dynamic range with −106 dB THD+N. For mixing, low-noise outputs mean the hiss floor stays below what most monitors and rooms reveal. The headphone outputs are rated at 118 dB dynamic range and up to +16 dBu, which drives a wide range of headphones.

Routing and direct monitoring are handled in Focusrite Control on supported systems, where you can build low-latency monitor mixes for each headphone output.

Included software

Focusrite lists Ableton Live Lite, Pro Tools Intro+ and the Hitmaker Expansion bundle with plugins from companies such as Antares, Softube and XLN Audio. Bundles change over time, so check Focusrite’s page before buying for a specific plugin.

Who should consider the Clarett+ 4Pre

• Home studios that record a vocalist and two or three instruments at once.
• Producers who own analogue synths and want line inputs that are always connected.
• Anyone planning to grow into a full drum recording setup through ADAT.
• Engineers who want two independent headphone mixes.

Who should look elsewhere

If you only record one or two sources at a time, a two-input interface such as the Clarett+ 2Pre or Scarlett 2i2 does the same job with less desk space. If you need eight preamps in one box without ADAT, the Clarett+ 8Pre is the next step. If you want to monitor through DSP plugins while tracking, look at an interface with onboard processing.

Common mistakes with a multi-input interface

• Leaving Air on for every channel, which can stack brightness across a whole drum kit.
• Enabling 48 V phantom power on a channel used by a vintage ribbon microphone without checking the manufacturer’s guidance.
• Setting the ADAT preamp to a different sample rate from the session, which causes clicks or no signal.
• Recording peaks near 0 dBFS. At 24-bit, peaks around −12 to −6 dBFS leave headroom without adding audible noise.

Setup checklist

1. Run Focusrite’s Easy Start tool and install Focusrite Control if your system needs it.
2. Select the Clarett+ 4Pre as input and output device in your DAW.
3. Choose your sample rate before connecting ADAT gear, and set the external preamp as clock master or slave consistently.
4. Gain each microphone while the performer plays at full volume.
5. Create a headphone mix for each output in Focusrite Control.

How to choose an audio interface walks through the input count question in more detail, and our recording and mic technique hub covers microphone placement for each of the sessions above.

How to set up the Focusrite Clarett+ 4Pre for a session

The checklist below covers the basics. This section goes step by step through a full first session.

1. Install Focusrite Control

Install Focusrite Control before connecting. On Windows, it includes the ASIO driver. On a Mac, it manages routing and hardware settings. Then check for firmware updates.

2. Power and connect

Connect power as shown in the user guide, then the USB-C cable. Use a direct port on the computer rather than a hub when possible.

3. Set rate and buffer

Choose 44.1 or 48 kHz in both the DAW and Focusrite Control. These rates also give you all eight ADAT channels. Set a 64 or 128 sample buffer for tracking.

4. Plan the inputs

Use preamps 1 to 4 for microphones. Use the two front JFET inputs for guitar or bass. Then use the four fixed line inputs at the rear for synths or a drum machine. Fixed inputs have no gain knob, so set the level at the source.

5. Build two headphone mixes

The 4Pre has two headphone outputs. In Focusrite Control, create a separate direct-monitoring mix for each. For instance, the engineer hears a full mix while the singer hears more vocal.

6. Set gain and test

Set each preamp at the loudest part of the performance. Aim for peaks near −12 dBFS. Record a short test, then listen on monitors before the main takes.

A four-mic drum and vocal plan

Four preamps can capture a compact drum setup. Use one mic on the kick, one on the snare, and two overheads. That is a classic and effective approach for rock and pop demos.

Alternatively, record a small band live. Put vocals on preamp 1, an acoustic guitar mic on preamp 2, and a stereo pair on the room. Then plug bass into a JFET instrument input and keys into the rear line inputs.

If you need more mics, add an eight-channel ADAT preamp. Set one unit as clock master and the other to follow. That expands the 4Pre to 18 inputs in total.

Clarett+ 4Pre vs related interfaces

The table compares published figures from Focusrite. Visit the official Clarett+ 4Pre page for the full list.

Spec	Clarett+ 4Pre	Clarett+ 2Pre	Clarett+ 8Pre	Scarlett 18i20 (4th Gen)
Mic preamps	4	2	8	8
Mic gain	57 dB	57 dB	57 dB	69 dB
Mic EIN	−129 dBu	−129 dBu	−129 dBu	−127 dBu (A-wtd)
Inputs / outputs	18 / 8	10 / 4	18 / 20	26 / 26
Headphone outputs	2	1	2	2
ADAT	8 in	8 in	8 in, 8 out	Dual in and out
MIDI	In/out	In/out	In/out	In/out
Auto Gain	No	No	No	Yes

The 4Pre sits in the middle. It doubles the 2Pre’s preamps and adds a second headphone output. The 8Pre adds more preamps and outputs. The 18i20 trades a little preamp noise for Auto Gain and more digital I/O.

Pros and cons

Pros

• Four low-noise preamps at −129 dBu EIN.
• Two headphone outputs for separate mixes.
• Four fixed line inputs for synths and drum machines.
• ADAT input for eight more channels.
• 124 dB line output dynamic range.
• Analogue Air on each preamp.

Cons

• 57 dB of gain is limited for quiet speech on low-output dynamics.
• Four line outputs only, with no ADAT output.
• No Auto Gain or Clip Safe.

Using the fixed line inputs

The four rear line inputs are fixed at +18 dBu maximum. They have no gain control. Therefore, set the level on the synth or drum machine itself. Turn the source up until the DAW peaks sit around −12 dBFS.

These inputs are ideal for keeping gear permanently connected. For example, wire a stereo synth to inputs 5 and 6 and a drum machine to 7 and 8. Then the front preamps stay free for mics and guitars. Nothing needs re-plugging between sessions.

Gain staging across four channels

With four mics, levels interact. Set each preamp on its own first. Then listen to all channels together. Bleed from a loud source, such as drums, can raise the level on nearby mics.

Record at 24-bit and leave headroom. Average levels near −18 dBFS with peaks around −10 dBFS keep you safe. Since there is no Auto Gain, watch the meters closely during the first take.

On the output side, the line outputs reach +18 dBu. Use the monitor control for volume and keep the DAW master near unity.

Who should buy the 4Pre and who should skip it

Buy it if you need four clean preamps, two headphone mixes and room to grow. It suits project studios, small bands and producers with outboard synths. Skip it if you mainly record one voice at a time. Skip it too if you need many analogue outputs or ADAT out, because the 8Pre covers that.

Common setup mistakes to avoid

• Two clock masters with ADAT. Pick one master to avoid clicks.
• Turning fixed inputs up at the interface. They have no gain knob; adjust the source.
• Air on bright sources. It is recorded and cannot be removed.
• Mismatched sample rates. Keep the DAW and Focusrite Control the same.

Using the 4Pre with an iPad

Focusrite lists iPadOS compatibility over USB-C. That makes the 4Pre an option for mobile recording on a tablet. Connect it with a suitable USB-C cable, then open a recording app that supports multichannel input.

Keep the session simple on a tablet. Fewer tracks and plugins put less load on the device. Test the setup at home before a live recording, so that surprises happen in private.

Monitoring with two speaker pairs

The four balanced outputs let you run two speaker pairs. Use outputs 1 and 2 for main monitors and 3 and 4 for a smaller reference pair. Then switch between them in Focusrite Control to compare mixes.

Comparing on small speakers is a quick check of the vocal and bass balance. If the mix holds up on both, it usually translates well elsewhere. Match the volume of the two pairs before comparing, because louder playback tends to sound better.

Finally, label each DAW input to match the physical channel. It prevents recording to the wrong track when a session gets busy.

Final checks before your first Focusrite Clarett 4Pre session

Before recording anything important, run a short checklist. Confirm the Clarett+ 4Pre appears in your DAW at the right sample rate. Check that every input shows signal on its meter. Make sure the headphones and speakers both play back. Then record ten seconds, play it back and listen closely for noise or clicks. That small habit catches most problems early.

FAQ

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