Connecting two microphones to a single audio interface lets you record two voices at once to separate tracks, host a co-hosted podcast without sharing a mic, or capture stereo room sound with full control over each channel. By the end of this guide you will have both mics plugged into one interface, routed as two independent inputs in Windows and in your recording software, with correct gain, phantom power, and monitoring. This works for any 2-input (or larger) interface with two preamps.
Prerequisites: A computer running Windows 10 or Windows 11, an audio interface with two mic preamps and XLR or combo inputs, two microphones with matching cables, and a DAW or recording app such as Audacity, Reaper, Audacity, OBS Studio, or Ableton Live. You should have administrator access to install the interface driver if needed.
Before You Start
| What you need | Why | Optional? |
|---|---|---|
| Audio interface with 2 mic preamps (e.g., Focusrite Scarlett 2i2, PreSonus AudioBox USB 96, MOTU M2) | Provides two independent preamps and analog-to-digital converters so each mic gets its own channel | No |
| 2x XLR cables (or XLR for dynamic mics, XLR for condenser mics) | Balanced connection to combo input reduces noise and carries phantom power when needed | No |
| 1x or 2x microphones (dynamic or condenser) | Your sound sources; can be same model or mismatched | No |
| USB-C or USB-A cable supplied with interface | Data and power connection to computer; use rear USB port for stable power | No |
| Closed-back headphones plugged into interface headphone jack | Lets you monitor direct signal without latency and set gain accurately | Yes – recommended |
| Interface driver/software (Focusrite Control, Universal Control, MOTU M-Series driver) | Enables ASIO driver, firmware control, and low-latency performance on Windows | Yes – required for most interfaces, not needed for class-compliant devices |
| Mic stands and pop filters | Isolates handling noise and controls plosives when two people share a desk | Yes |
Step-by-Step
Step 1: Install the Interface Driver and Set Windows Defaults – Time: 5 minutes
Unplug the interface first. Download the current driver from the manufacturer support page for your exact model and run the installer as administrator. Restart when prompted, then connect the interface to a rear USB port on your desktop or a direct port on your laptop. Avoid USB hubs for initial setup.
In Windows, go to Settings > System > Sound. Under Output, set your interface as the output device, for example Speakers (Focusrite USB Audio) or Speakers (MOTU M Series). Under Input, you will see the interface listed as a single device; that is normal. Click More sound settings > Recording tab > select your interface > Properties > Advanced tab > set Default Format to 2 channel, 24-bit, 48000 Hz (Studio Quality) and check both boxes under Exclusive Mode. Click Apply > OK. This forces Windows to see both channels at a production sample rate.
Step 2: Connect Both Microphones Correctly – Time: 3 minutes
Turn the gain knobs for Input 1 and Input 2 fully counter-clockwise and make sure the 48V phantom power button is off. Plug Mic A into Input 1 with an XLR cable and Mic B into Input 2 with a second XLR cable. Push until the XLR latch clicks. If you use 1/4-inch TRS for a dynamic mic, use the center of the combo jack, but XLR is preferred for mics.
Only then decide on phantom power: If both mics are condensers that require 48V (e.g., Audio-Technica AT2020, Rode NT1), press the 48V button(s). Many 2-channel interfaces have a single global 48V switch; that is safe for a second dynamic mic like a Shure SM58 that is wired with a balanced XLR, but do not enable 48V if your second mic is a ribbon mic or uses an unbalanced cable. If only Input 1 is a condenser, use an interface with per-channel 48V or enable global 48V only if the other mic is a balanced dynamic. Wait 10 seconds after enabling before recording.
Step 3: Set Gain Structure and Enable Direct Monitoring – Time: 5 minutes
Put on headphones connected to the interface. On the interface, turn on Direct Monitor or press the Direct button so you hear input without software latency. Set the monitor mix knob to Input or fully clockwise to Direct if available.
Have each person speak at their loudest normal level about 6 to 8 inches from the mic. Slowly raise the Gain knob for Input 1 until the halo LED stays green and flashes amber on peaks, but never hits solid red. Aim for peaks around -12 dB to -6 dB on the interface meter. Repeat for Input 2. Keep gain within the interface range, typically 0 dB to +56 dB for Scarlett-style preamps; most voices sit between 40% and 70% rotation for dynamic mics and 25% to 50% for condensers. If you have pad or Air buttons, leave them off initially. Engage the pad (-10 dB) only if you cannot keep the signal out of red at minimum gain.
Step 4: Route Two Separate Inputs in Your DAW – Time: 6 minutes
This is where one interface becomes two independent tracks. The exact path depends on your software:
Audacity: Go to Edit > Preferences > Audio Settings. Set Host to WASAPI or Windows DirectSound for testing, and for low-latency multitrack use MME is not recommended. For ASIO, you need an ASIO build. Set Recording Device to your interface (e.g., Focusrite USB ASIO) and Channels to 2 (Stereo). When you record, Audacity captures Input 1 as Left and Input 2 as Right. Click the dropdown on the track > Split Stereo to Mono to edit each mic separately. For dedicated mono tracks, use Audacity 3.4 or later: Transport > Transport Options > Enable Record on a new track.
Reaper: Go to Options > Preferences > Audio > Device. Set Audio System to ASIO and ASIO Driver to your interface driver. Set Enable Inputs to First: Input 1 / Last: Input 2. Create two tracks: Track > Insert new track (press Ctrl + T twice). On Track 1, click the Input dropdown > Input: Mono > Input 1. Arm record (red button). On Track 2, set Input: Mono > Input 2 and arm. Click the Record Arm button on both.
OBS Studio: Go to Settings > Audio > Global Audio Devices > set Mic/Auxiliary Audio to your interface. For separate control, instead go to Sources > click + > Audio Input Capture > Create New > Device = Focusrite USB Audio Input 1 and add a second Audio Input Capture with Device = Input 2. Right-click each source > Advanced Audio Properties > set each to Mono.
Ableton Live: Go to Options > Preferences > Audio > Driver Type = ASIO > Audio Device = Focusrite USB ASIO. Then go to Input Config > enable Stereo 1/2 and Mono 1 and Mono 2. Back in Session View, set Track 1 Audio From to Ext. In 1 and Track 2 Audio From to Ext. In 2. Set Monitor to Off or Auto.
Set Sample Rate to 48000 Hz and Buffer Size to 128 or 256 samples under your interface control panel for recording. This path is usually found at C:\Program Files\Focusrite\Scarlett or via the system tray icon > right-click > Settings.
Step 5: Set Levels, Pan, and Headphone Mix – Time: 4 minutes
In your DAW, keep each track fader at 0.0 dB (unity) and adjust with the interface gain knobs, not the software fader. Pan Track 1 hard left and Track 2 hard right only if you need a quick stereo check; for podcast or voice work keep both tracks centered (pan C) and export as mono or dual mono.
To create a headphone mix without echo: In Reaper go to Track > Route > uncheck Master Send on both tracks if you want direct-only monitoring, or keep Master Send on and set Record Monitoring to OFF while using the interface Direct Monitor button. In Focusrite Control or similar software go to Output Routing > set Headphone Output to Custom Mix > drag Input 1 and Input 2 faders to 0 dB to hear both equally.
Step 6: Record a Test and Save a Template – Time: 3 minutes
Press Ctrl + R in Reaper or R in Audacity or the Record button in OBS to record a 20-second test where each person counts 1-2-3 alternately. Stop with Spacebar or Ctrl + Space.
Check that Track 1 only moves when Mic A is spoken into and Track 2 only moves for Mic B. Save the project as a template for future use: In Reaper go to File > Project Templates > Save project as template. In Audacity go to File > Save Project > Save Project As and store the .aup3 file in C:\Users\YourName\Documents\Audacity\Templates. This way the current interface routing, sample rate, and track inputs reload instantly next time.
Verify It Worked
Play back the test recording on headphones. You should hear Mic A only from Track 1 and Mic B only from Track 2 with no bleed if you mute the opposite track. In your DAW meters, each track should peak independently between -12 dB and -6 dB during normal speech. In Windows, go to Settings > System > Sound > More sound settings > Recording > double-click your interface > Listen tab > uncheck Listen to this device to avoid double monitoring, then Levels tab > verify the level meter moves for both channels when you tap each mic.
Confirm files are separate: In Reaper check your project folder at C:\Users\YourName\Documents\REAPER Media\ for two .wav files if you recorded in multitrack; in Audacity press View > Show Clipping to ensure no red clipping lines. If you see continuous waveforms on both tracks and hear no crackle, latency, or echo, the setup is complete. The dual-mic workflow remains the standard for two-person recording in 2026 because single-interface dual preamps offer lower noise than adapters or splitters.
Mistakes to Avoid
Mistake 1: Using a Splitter Cable or Y-Adapter to Combine Two Mics Into One Input
What causes it: A single XLR or 1/4-inch Y-cable ties two mics to one preamp, forcing them to share gain and phantom power and causing phase cancellation.
How to check: If turning the gain for Input 1 changes the volume of both voices, or if you see only one input meter moving for two mics, you are combined. In Settings > System > Sound > Input the device will show 1 channel instead of 2 channel when configured incorrectly.
What to do: Remove the splitter. Plug each mic into its own input with its own XLR cable: Mic A to Input 1, Mic B to Input 2. Reconfigure your DAW inputs as Mono Input 1 and Mono Input 2 as described in Step 4.
How to undo: If you need to revert for a single-mic session, just unplug the second mic and set your DAW track back to Input: Mono > Input 1. No driver changes needed.
Mistake 2: Enabling Phantom Power Incorrectly
What causes it: Leaving 48V off for a condenser results in silence or very low noise, while leaving 48V on with a ribbon mic or unbalanced cable can damage the element. Toggling 48V while gain is up creates a loud pop.
How to check: If a condenser is extremely quiet or silent while a dynamic on the other input works, check the 48V LED on the interface. Listen for hiss vs. silence. In your DAW, the track for the condenser will show a flat line.
What to do: Turn both gain knobs down, mute your monitors or headphones, then press the 48V button to match the mic type. Wait 8 to 10 seconds, then slowly bring gain back up. Never hot-plug XLR cables with 48V enabled; mute, disable 48V, swap cables, re-enable.
How to undo: Turn gain down, disable 48V, wait 5 seconds, unplug condenser. Dynamic mics will continue to work without 48V. If you damaged a ribbon, discontinue use and have it inspected.
Mistake 3: Recording Both Mics to a Single Stereo Track and Trying to Fix It Later
What causes it: Setting Audacity or OBS to Stereo with one stereo track records Input 1 as left and Input 2 as right interlocked. You lose independent level control, EQ, and noise gate per voice.
How to check: After recording, if you cannot mute or apply effects to one voice without affecting the other, or if the waveform shows as one stereo file with left and right linked, you recorded to a single stereo track. In Audacity the track label will say Stereo, 48000 Hz, 32-bit float.
What to do: Create two mono tracks before recording. In Reaper set each track to Input: Mono > Input 1 and Input: Mono > Input 2. In Audacity record in stereo then immediately click the track dropdown arrow > Split Stereo to Mono, or set Recording Channels to Mono and record pass one at a time if needed. In OBS use two Audio Input Capture sources as described above.
How to undo: If you already recorded stereo, split to mono as above, then delete the unwanted channel from each track. Use File > Export > Export Multiple in Audacity to re-export as two mono files. No need to re-record if levels were healthy.
Mistake 4: Monitoring Through Software and Direct at the Same Time
What causes it: Enabling both Direct Monitor on the interface and Software Monitoring (Input Monitoring) in the DAW creates a doubled, echo-like sound with a short delay of 5 to 20 milliseconds.
How to check: If you hear your voice twice, once immediate and once slightly delayed, or see latency reported as 10+ ms in your DAW performance meter, you have double monitoring enabled. Test by clapping once and listening for two claps.
What to do: Choose one method. For lowest latency, keep Direct Monitor ON on the interface and in your DAW set Monitor to Off. Path: In Reaper click the speaker icon on each track until it shows Off; in Ableton set Monitor to Off; in Audacity go to Edit > Preferences > Recording > uncheck Software Playthrough of input. Adjust buffer size to 128 samples if you prefer software monitoring instead, then turn Direct Monitor OFF.
How to undo: Simply toggle the Direct Monitor button back or re-enable software monitoring via the same menu paths. No restart required.
FAQ
Can I connect two USB microphones to one interface?
No. USB microphones have a built-in interface and cannot plug into an XLR interface input. If you have two USB mics, connect both directly to the computer via USB and aggregate them, or better, replace them with two XLR mics for your interface. On Windows go to Settings > System > Sound and you will see each USB mic as a separate input device, but you cannot merge them into one ASIO device without extra software and they will drift out of sync. For reliable dual-mic recording, use XLR mics into the interface and set the interface as the single Audio System > ASIO driver in your DAW.
Do I need two identical microphones?
No, but matching mics simplifies EQ. You can mix a dynamic on Input 1 and a condenser on Input 2 as long as you handle gain and phantom power correctly. Set gain independently so each peaks between -12 dB and -6 dB, and do not use global 48V if one mic is a ribbon. In post-production, you can color-correct the brighter condenser with a high-shelf cut around 8000 to 12000 Hz and add a high-pass filter at 80 to 100 Hz on the dynamic to match. Keep distance consistent at 6 to 8 inches to maintain similar room tone.
Why is only Input 1 showing sound and Input 2 is silent?
The track is likely set to Input 1 for both tracks or Windows is set to mono. First, check physical cabling and the mic mute switch. Then in your DAW verify Track 2 is set to Input: Mono > Input 2, not Input 1 or Stereo. In Reaper go to Options > Preferences > Audio > Device and confirm Last input is Input 2. In Windows go to Settings > System > Sound > More sound settings > Recording > Properties > Advanced and confirm 2 channel mode. Raise Input 2 gain while speaking and watch the interface LED; if the LED moves but DAW does not, re-arm the track with the red Record Arm button and disable exclusive mode for other apps under Settings > System > Sound > More sound settings > Recording > Advanced > uncheck Allow applications to take exclusive control of this device, click Apply, then restart the DAW.
How do I export two mics as separate files for editing?
Record to two mono tracks as in Step 4, then export multitrack. In Reaper go to File > Render > Source = Stems (selected tracks) > Bounds = Entire Project > Directory = C:\Users\YourName\Documents\REAPER Renders\ > set Sample rate 48000 Hz, Channels Mono > press Render 2 files. This creates Track01_MicA.wav and Track02_MicB.wav with identical start times. In Audacity solo Track 1 then File > Export Audio > Export Selected Audio > set Format WAV, 24-bit > name MicA.wav, then solo Track 2 and repeat. In Adobe Audition use File > Export > Multitrack Mixdown > Entire Session > check each track to export as separate files. Keep files at 48kHz/24-bit to preserve headroom for later mixing.
