Abstract
This paper presents the MAC mini (2024) introduced in October 2024, which is equipped with the M4 chip and offers a high cost-performance ratio. However, it lacks a built-in recording function. After experimenting with numerous free or trial versions of recording software, the author selected Loopback. This software functions as a virtual mixing console, capable of intercepting internal audio signals and enabling simultaneous audio and video recording during screen capture. The article elaborates on its straightforward installation and detailed configuration process, describes the volume display and line switch operations of the virtual mixing console, and also explains the techniques for hiding and showing the software as per requirements, thereby providing a solution to enhance the recording capabilities of the MAC mini (2024).
Logical Structure
I. The New and Cost-Effective MAC mini (2024)
In October 2024, Apple launched the MAC mini (2024) computer host. This device is equipped with the latest M4 chip developed by Apple. Compared with the previous M1 and M2 chips, it not only exhibits enhanced performance but also features a more compact and refined design. Among them, the low-configuration version (with 256G memory), although humorously referred to as the "entry-level version", has attracted significant attention due to its outstanding cost-performance ratio.
II. The Drawback of the Absent Internal Recording Function
The author purchased a MAC mini (2024) with anticipation. Upon usage, the device's excellent performance was immediately evident and highly appreciated. However, it regrettably lacks a practical recording function, as it is devoid of both a physical microphone and a virtual one.
Nonetheless, it does possess a notably useful screen recording function. By simply pressing the combination of command + shift + 5 keys, a screen recording menu promptly appears. Users can then choose to record the full screen, a specific window, or even a custom area defined by the mouse cursor.
Unfortunately, while high-quality video images can be recorded, the accompanying audio is absent. Although an external microphone can be connected to address the recording issue, this leads to the sound from the speaker being re-recorded by the microphone, resulting in a significant degradation of sound quality and the inclusion of ambient noise, severely affecting the overall recording quality.
Therefore, the crux of the solution lies in identifying suitable software, specifically a virtual microphone application that can operate effectively within the computer's internal circuitry, allowing for the direct and accurate recording of corresponding audio during screen recording.
III. The Ingenious Working Principle of the Recording Software Loopback
The author dedicated three days to enabling the MAC mini (2024) to achieve a flawless recording function.
Fortunately, with the assistance of two AI applications, Kimi intelligent assistant and Doubao, considerable time and effort were saved during web searches. However, due to the initial difficulty in evaluating the merits of various recording software, nearly all available free or trial versions on the market, such as Soundflower, BlackHole, and OBS, were tested.
Ultimately, the focus shifted to the Loopback software.
This software resembles a mixing console in a professional recording studio, albeit a virtual one concealed within the computer.
Its working mechanism is as follows: It intercepts the audio signals of running programs (which would otherwise be directly transmitted to the speaker for playback), such as those generated by QuickTime Player, and utilizes them as its audio input sources. Subsequently, it samples and records these audio signals, storing them in specific files. For instance, when playing video content via QuickTime Player and initiating a screen recording, the Loopback software simultaneously records the audio into the newly created video file.
This ensures that when the recorded video is played back, a synchronized audio-visual experience is achieved.
Undoubtedly, this represents a relatively optimal solution for screen and audio recording on the MAC mini (2024).
IV. The Convenient Installation and Precise Configuration of the Software
The installation process of the Loopback software is remarkably straightforward. By following the installation prompts and clicking "Next" throughout, the installation can be completed effortlessly, similar to a user-friendly, step-by-step operation.
During installation, it was observed that the software could be integrated into the MAC mini's Launchpad. However, its integration into the Launchpad is somewhat analogous to an "acquaintance" of Apple, possessing a certain degree of familiarity but not an overly intimate connection. In contrast, some software, despite being frequently used, remains excluded from the Launchpad, such as the TexStudio software commonly employed for LaTeX document typesetting.
Upon opening the Loopback software, its interface comprises two main parts, divided into four distinct areas, as illustrated in Figure 2.
The leftmost area of the interface, though relatively small in size, constitutes the core functionality of the software.
Its primary role is to create virtual mixing consoles for the computer.
At the bottom of this area, pressing the "+" button allows for the swift creation of a mixing console. As depicted in Figure 2, a virtual mixing console named Loopback Audio has been established. If necessary, multiple virtual mixing consoles can be created by repeatedly pressing the "+" button, and unwanted ones can be deleted by pressing the "-" button.
The created virtual mixing console features two input terminals and two output terminals.
Examining the right side of Figure 2, it consists of three regions, namely left, middle, and right, which are responsible for configuring the input and output of the virtual mixing console.
The middle region displays the generated virtual mixing console, named Loopback Audio in this case.
Beginning with a relatively straightforward operation, the output device, officially known as the monitor and commonly referred to as the speaker, is configured in the right area.
In the author's MAC mini, two speakers are configured: the built-in MAC mini speaker and the IPS0001 speaker of the attached monitor. The configuration process is simple: click the "+" button next to "monitors" and select the desired speaker from the dropdown menu.
Once the configuration is complete, the virtual mixing console automatically establishes connections with the left and right channels of the speakers. (As shown in the right area of Figure 2)
However, the process of configuring the various input signals for the virtual mixing console proved to be somewhat time-consuming, taking approximately a full day to finalize.
The solution ultimately discovered was surprisingly uncomplicated: click the "+" button next to "Sources" in the left area and then select the desired software as the sound source from the “pop-up menu”. For example, the author added commonly used software such as QuickTime Player, Safari, WeChat, and zFuse by clicking on them one by one.
It is crucial to note that prior to adding these software as sound sources, they must be opened. Only when the software is active will it be visible in the menu; otherwise, it will not be available for selection.
Following a series of operations, all devices and their connection lines are clearly presented on the Loopback panel, as illustrated in Figure 2.
The audio signals generated by the four aforementioned software as sound sources are categorized into left and right channels and are then routed to the corresponding left and right channels of Output Channels. Subsequently, the audio signals are transmitted from the output terminals of Output Channels to the respective channels of the MAC mini and IPS0001 speakers.
At this stage, the connection and configuration between the virtual mixing console and all software and devices have been successfully completed.
In the illustrated panel, each device is equipped with a switch. "On" indicates that the sound line is connected and active, while "Off" signifies that the line is disconnected.
For example, in the left area panel, "Loopback Audio" is in the "On" state, indicating that the virtual mixing console is operational, and the small icon below reveals that it has four software sources: QuickTime Player, Safari, WeChat, and zFuse.
The same applies to each device in the right area.
V. The Efficient Operation of the Virtual Mixing Console
When a sound source software, such as QuickTime Player, is opened, a portion of the left and right channel bars of QuickTime Player on the Loopback panel will turn blue. The proportion of the blue area represents the magnitude of the input volume. The connected subsequent devices, Output Channels, as well as the MAC mini speaker and the IPS0001 speaker, will also display blue bars of the same length.
For other software, if they are not opened or are in a silent state, the volume bars will remain gray. This state is depicted in Figure 3.
The volume bar at the small speaker below the Devices panel on the left is blue and indicates 100% volume. At this setting, the sound of any device sound source will be recorded at full volume. If necessary, the volume can be adjusted by sliding the bar left or right to control the input volume level.
At this point, the virtual mixing console within the MAC mini is fully operational. By toggling the "On" or "Off" switches of software or devices, the sound transmission of various software or devices can be conveniently enabled or disabled.
Referring to the configuration in Figure 3, when an audio signal is present, both the MAC mini speaker and the IPS0001 speaker on the monitor will emit sound. If only the MAC mini speaker is desired to produce sound, the switch of the IPS0001 speaker can be slid to the "Off" position.
VI. The Concealment and Revelation of the Virtual Mixer
Subsequently, let us delve into the concealment and revelation features of the virtual mixer itself.
Open the "Other" option in the Launchpad and then select "Audio MIDI Setup".
At this juncture, it will be noticed that a new device named "Loopback Audio" has been added to the current "Audio Devices" list (as shown in Figure 4). Its characteristics are described as 2 inputs and 0 outputs, indicating that it possesses only a dual-channel input function without a corresponding dual-channel output. This implies that it is a dedicated sound input device, or more colloquially, a virtual internal microphone, and is represented by a microphone-shaped icon in the device list to signify its function.
This is entirely in line with the original intention of creating Loopback Audio.
One of the most significant application scenarios of Loopback Audio is its ability to record sound synchronously during screen recording. At this time, when the combination of command + shift + 5 keys is pressed, Loopback Audio can be selected from the microphone options in the popped-up screen recording menu (as shown in Figure 5).
Nevertheless, in most cases, the functionality of Loopback Audio may not be required. In such instances, simply return to the Loopback panel and switch the Loopback Audio in the leftmost Devices to the "Off" state. Its state is illustrated in Figure 6.
At this moment, if the "Audio Devices" list is reexamined, it will be found that the previously existing Loopback Audio has vanished without a trace.
In this manner, when the need arises, the Loopback software can be utilized to seamlessly address the issue of synchronous recording during screen recording. Conversely, when not needed, it can be concealed, ensuring that no system resources are occupied, thereby achieving a high level of convenience, efficiency, and flexibility.
Through the above steps, a highly effective recording solution for the MAC mini (2024) has been successfully devised, enhancing the functionality of this high-performance device and enabling it to better meet the diverse requirements of daily work, study, and entertainment. Whether it is recording online meetings, online courses, or creating video tutorials and music works, it can be effortlessly accomplished, providing users with an enhanced user experience.
It is hoped that the above content will prove beneficial to users of the MAC mini (2024) who are grappling with recording functionality issues, allowing them to fully harness the potential of this device and produce more outstanding audio and video creations.
