AirCheck Guides · Support · Home

Guides / Virtual audio drivers and Audio MIDI Setup

What is a virtual audio driver, and when do you need one on a Mac?

Updated 2026-09-03.

A virtual audio driver is a software audio device with no hardware behind it: whatever an app sends to its output appears on its input, so another app can read it. On a Mac it is a Core Audio plug-in in /Library/Audio/Plug-Ins/HAL; BlackHole (free) and Loopback ($99) are the current ones. You need one to route or mix audio between apps. Since macOS 13 you do not need one to record what you hear.

What is a virtual audio driver?

Every audio device a Mac app can see is presented by Core Audio. A physical interface gets there through a USB driver; a virtual audio driver gets there through a small plug-in that coreaudiod loads from /Library/Audio/Plug-Ins/HAL, with no hardware at all. Inside the plug-in, the output channels are connected straight to the input channels. This is called a loopback: sound goes in one side and comes back out the other, inside the computer, in real time.

Existential Audio's description of BlackHole is the cleanest definition: a virtual audio loopback driver that allows applications to pass audio to other applications with zero additional latency. Because the device looks ordinary to every app, any app can choose it as an output (sending sound into the loop) and any app can choose it as an input (reading sound out of the loop). That is the entire trick.

Examples in 2026: BlackHole (free, open source, 2, 16 or 64 channels), Loopback by Rogue Amoeba ($99, a driver plus a routing app), and the retired Soundflower kext. Apps install private ones too: on the author's Mac, Microsoft Teams, Serato and the Pioneer DDJ-SZ each add a plug-in to that folder. The Audio MIDI Setup guide shows where they appear.

When do you need a virtual audio driver?

Whenever audio must move between two running apps, live, and neither app can talk to the other directly. Three cases cover it:

  1. App-to-app routing. A DAW's master bus into OBS for a livestream, a browser tab into Ableton Live for sampling, Serato's output into a video call. The sending app's output is set to the driver; the receiving app's input is set to the driver. BlackHole does this for free.
  2. Mixing several sources into one stream. Your microphone plus a game plus a music player, summed into one virtual device that Zoom or a recorder sees as a single input. Plain BlackHole cannot sum sources; you need an aggregate device for side-by-side channels or Loopback for a real mix with per-source volume.
  3. A virtual microphone. Playing a sound file, a soundboard or a translated voice into a call as if it were your mic. The driver is the only way to make macOS present software output as a microphone.

In every case above a driver is the right tool because something has to happen to the audio in real time while other apps use it. Making a file afterwards is a different problem.

When do you not need a virtual audio driver?

Three cases where people install one and did not have to:

  1. Recording what the Mac plays. Since macOS 13 Ventura, Apple's ScreenCaptureKit captures system audio for any app with the Screen & System Audio Recording permission. Apple's WWDC22 introduction states you can capture screen content from displays, applications and windows "as well as the audio that goes with it." OBS Studio's macOS audio capture and audio-only recorders such as AirCheck use it. No device is created, so the speakers, the volume keys and Audio MIDI Setup are untouched.
  2. Recording a microphone or an interface. Those are already Core Audio inputs. QuickTime, Voice Memos, GarageBand and every recorder can open them. A multi-channel interface such as a Focusrite Scarlett 8i6 is one device with many channels; a recorder with a channel picker takes the pair you want.
  3. Screen recording with sound. Same API. The built-in screenshot toolbar records the mic only, but ScreenCaptureKit-based apps record the screen with system audio directly. See screen recording with internal audio.

The test: does the audio need to arrive somewhere else while it plays, or do you just want a file afterwards? Only the first needs a driver. Most "record internal audio with BlackHole" tutorials predate macOS 13.

What does a virtual audio driver cost you in setup and side effects?

The drivers themselves are safe, and BlackHole is free, so the cost is in configuration and in what breaks while it is selected:

None of this is dangerous; all of it is time, and each item is a place where a take can come out empty.

Which virtual audio driver should you pick on a Mac?

Two live choices, one dead one:

If your task is in the "do not need one" list, pick a recorder instead; prices, setup effort and mixing are compared in Loopback vs BlackHole vs no driver.

You can capture screen content from any combination of displays, applications, and windows as well as the audio that goes with it.

Apple, WWDC22 session Meet ScreenCaptureKit

Mac audio tasks and whether a virtual driver is required (3 Sept 2026)

TaskVirtual driver requiredBuilt-in or driverless pathThird-party optionPrice of that option
Record what the Mac plays to a fileno (macOS 13 or newer)ScreenCaptureKit recorder, one permissionAirCheck, or OBS (video file)$39, or free
Record a mic or audio interfacenoQuickTime, Voice Memos, any recorderAirCheck (channel-pair picker)$39
Send a DAW or browser into OBS or a callyesnoneBlackHolefree
Mix mic plus several apps into one inputyesnone (aggregate only stacks channels)Loopback 2$99
Use software output as a microphone in a callyesnoneBlackHole or Loopbackfree or $99
Two interfaces in one DAW sessionnoAggregate Device in Audio MIDI Setupnone neededfree

Prices from rogueamoeba.com and existential.audio on 3 Sept 2026. AirCheck requires macOS 14 or newer.

Where AirCheck fits

AirCheck ($39, macOS 14 or newer) exists for the first two rows of the table: recording what the Mac plays, or recording any Core Audio input, without installing a driver. It uses ScreenCaptureKit for system audio, so no device is added and your speakers keep working, and it opens interfaces directly with a channel-pair picker for multi-input units. Files are 24-bit at the device rate, exported as WAV or MP3, and a watchdog restarts a stalled capture into the same file after 5 seconds.

When you do not need it: For the routing, mixing and virtual-microphone rows you need BlackHole or Loopback; AirCheck records one source per take and does not route audio anywhere.

AirCheck records what your Mac plays, or any input, to one file. $39 once.

Buy AirCheck for $39

macOS 14 or newer. One-off payment. Fourteen-day refund, no questions asked.

Questions people ask

How do you loopback audio on a Mac?

Install a loopback driver such as BlackHole, set the sending app's output to BlackHole 2ch, and set the receiving app's input to BlackHole 2ch. To keep hearing the sound, create a Multi-Output Device in Audio MIDI Setup with your speakers first and BlackHole second.

Do I need BlackHole to record internal audio on a Mac?

Not on macOS 13 or later. ScreenCaptureKit lets recorders capture system audio directly after a Screen Recording permission. BlackHole is still needed to move audio between two apps live, for example a DAW into OBS.

What is the best virtual audio driver for Mac in 2026?

BlackHole for free app-to-app routing (GPL-3.0, no kernel extension, Apple silicon supported). Loopback 2 ($99) if you need to mix sources and monitor without building Audio MIDI Setup devices. Soundflower is deprecated and does not run on Apple silicon.

Sources

Hannes Hennerbichler builds AirCheck and records his own DJ sets with it through a Focusrite Scarlett 8i6. Every step on this page was run on the macOS version stated above. Drafted with AI assistance, checked and edited by the author. About