MOTU M4 vs Universal Audio Volt 4: Which Audio Interface Reigns Supreme?

The MOTU M4 USB-C Audio-MIDI Interface and the Universal Audio Volt 4 Portable 4x4 USB Audio/MIDI Interface are two robust and high-quality options for audio recording and production, each with its own unique features and strengths.
The MOTU M4 stands out with its ultra-low latency performance and superior audio quality. It features ESS Sabre32 Ultra DAC technology, ensuring crystal-clear sound with a dynamic range of 120 dB. The M4 offers a 4-in/4-out configuration, which includes two mic/line/instrument inputs with individual preamps on the front panel and two additional line inputs at the back. It also has MIDI I/O, making it versatile for musicians who need to integrate MIDI gear. The full-color LCD screen on the front panel provides detailed metering for all inputs and outputs, a feature that enhances the user experience by allowing precise monitoring. The USB-C connectivity ensures fast and reliable data transfer, making it compatible with modern computer setups.
On the other hand, the Universal Audio Volt 4 is designed with a vintage analog sound in mind. It features a built-in 610 analog preamp and the ability to switch on a vintage mode to add warmth and richness to your recordings, a nod to UA's classic analog gear. The Volt 4 also offers a 4-in/4-out configuration but includes two combo mic/line/instrument inputs and two additional line inputs. Its MIDI I/O capabilities ensure it’s well-suited for a range of studio setups. The device is USB-powered, which adds to its portability, and it connects via USB-C for modern connectivity. The rugged, retro-inspired design of the Volt 4 not only looks great but is durable for on-the-go recording.
Both interfaces are equipped with loopback functionality, making them ideal for live streaming and podcasting. However, the MOTU M4's real-time metering and superior DAC technology make it a go-to for professionals who prioritize audio fidelity and precise control. Conversely, the Universal Audio Volt 4's vintage preamp mode and renowned UA analog sound appeal to users looking to infuse their recordings with classic warmth and character.
In summary, the choice between the MOTU M4 and the Universal Audio Volt 4 will largely depend on your specific needs and preferences. The MOTU M4 excels in technical performance and detailed monitoring, making it perfect for those who demand top-notch audio quality and real-time control. The Universal Audio Volt 4, with its vintage preamp and rugged design, is ideal for those who want to add a touch of analog warmth to their recordings and require a portable, stylish interface.

In-Depth Specification Comparison and User Reviews

Universal Audio Volt 4 Portable 4x4 USB Audio/MIDI Interface

MOTU M4

User Rating Based on Analysis of Reviews
	Purchase Value 87% of users found the MOTU M4 USB-C Audio Interface to be a great value for money, highlighting its competitive pricing compared to other interfaces with similar features. Many appreciated the high-quality preamps and low-latency performance, which are often found in more expensive models. Users noted that the interface provided excellent sound quality and a robust build, making it a worthwhile investment for both amateur and professional audio creators. 13% of users expressed dissatisfaction with the purchase value, feeling that the interface did not meet their expectations in terms of performance relative to its price. Some users encountered issues with the software or compatibility with certain operating systems, which they felt detracted from the overall value. Additionally, a few users mentioned that other brands offered similar features at a lower cost. 87% Sound Quality 92% of users were highly satisfied with the sound quality provided by the MOTU M4. They praised its clear and transparent audio output, which significantly improved their recording and playback experience. Many users appreciated the pristine sound and the high-quality DA converters, which they felt allowed for professional-level recordings without colorization of the input signal. 8% of users were not satisfied with the sound quality, mainly due to individual preferences or specific issues with their setup. Some reported that the sound output did not meet their expectations for clarity or depth, which may be attributed to mismatched equipment or improper calibration. A few users experienced noise or interference that they believed was related to the interface. 92% Build Quality 90% of users praised the MOTU M4 for its solid build quality. They appreciated the sturdy metal chassis, which provided durability and a premium feel. Many users noted that the interface could withstand the rigors of both studio use and on-the-go recording, and liked the high-quality knobs and buttons that enhanced the user experience. 10% of users were not satisfied with the build quality, citing issues such as loose knobs or buttons that felt flimsy. A few users experienced physical defects, such as poorly fitted parts or cosmetic damage. While these cases were relatively rare, they impacted the overall perception of the interface's durability for those affected. 90% Ease of Use 85% of users found the MOTU M4 user-friendly, highlighting its straightforward setup process and intuitive controls. Many appreciated the clear labeling and layout of the interface, which made it easy to navigate without prior technical experience. Users felt that the accompanying software was well-designed and complemented the hardware effectively, adding to the convenience of use. 15% of users found the MOTU M4 challenging to use, often due to difficulties with the initial setup or software installation. Some users mentioned that the documentation was not detailed enough, requiring them to seek additional help online. Others experienced configuration issues with certain DAWs, which took time to troubleshoot and resolve. 85% Software Compatibility 78% of users were satisfied with the software compatibility of the MOTU M4, reporting smooth integration with major digital audio workstations (DAWs) and operating systems. They appreciated the stable drivers and the ease of configuring the interface with their existing audio setups, which facilitated seamless recording and editing sessions. 22% of users encountered software compatibility issues, particularly with less common DAWs or older operating systems. Some reported driver instability or lag during sessions, which affected their workflow. A number of users also pointed out the lack of dedicated apps or support for mobile devices, limiting the interface's versatility for certain use cases. 78% Latency Performance 91% of users were highly satisfied with the latency performance of the MOTU M4, noting its low-latency monitoring capabilities and efficient driver performance. This aspect was particularly praised by musicians and producers who require real-time audio feedback for recording and mixing, as it allowed them to work without noticeable delay. 9% of users experienced latency issues, which they attributed to their specific computer configurations or the need for additional optimization. Some users found that latency increased when using multiple plugins or high sample rates, which disrupted their workflow and required adjustments to mitigate. 91% Customer Support 74% of users were satisfied with the customer support provided by MOTU, appreciating the responsive and helpful service they received when encountering issues with the M4. Many users found the support team knowledgeable and capable of resolving their problems efficiently, which increased their overall satisfaction with the product. 26% of users were dissatisfied with customer support, reporting slow response times and unhelpful resolutions to their inquiries. Some users felt that their issues were not adequately addressed, leading to prolonged downtime and frustration. A few also mentioned that the support resources available online were insufficient for troubleshooting their specific problems. 74% Portability 89% of users appreciated the portability of the MOTU M4, noting its compact size and lightweight design. This made it easy to transport and ideal for mobile recording setups or small studio spaces. Users liked that it could easily fit into a backpack or gear bag, making it convenient for musicians and producers on the move. 11% of users found the portability of the MOTU M4 lacking, primarily due to the need for additional cables or power sources in certain setups. Some users mentioned that while the size was compact, the interface did not feel as rugged as other portable options, causing concern about potential damage during transport. 89% Input/Output Options 82% of users were satisfied with the input/output options offered by the MOTU M4, highlighting the versatility provided by the combination of XLR, line, and MIDI inputs. Users enjoyed the ability to connect a range of instruments and devices, which made the interface suitable for various recording scenarios. 18% of users felt that the input/output options were limited, particularly for more complex audio setups. Some users desired additional inputs or outputs to accommodate larger sessions, while others found the lack of digital I/O options a drawback for integrating with certain studio equipment. 82% Design 88% of users appreciated the design of the MOTU M4, praising its sleek, modern look and intuitive control layout. The interface's aesthetic appeal and practical design elements, such as the large volume knob and clear metering displays, were frequently mentioned as positive aspects that enhanced the user experience. 12% of users were not satisfied with the design, citing minor ergonomic issues such as cramped control spacing or less intuitive button placement. Some users felt that the visual design could be improved for easier navigation during sessions, particularly in low-light environments. 88% Durability 86% of users were satisfied with the durability of the MOTU M4, noting its robust construction and resilience to wear and tear. Many users felt confident in its long-term performance, even with regular use in demanding environments. This aspect added to the perceived value and reliability of the interface. 14% of users expressed concerns about durability, often due to personal experiences with wear-related issues or defective units. Some users reported problems with connectors or components becoming loose over time, which affected their confidence in the interface's longevity. 86% Aesthetic Appeal 84% of users were pleased with the aesthetic appeal of the MOTU M4, appreciating its sleek, understated design that blended well with other studio equipment. Users liked the clean lines and professional appearance, which contributed to a positive perception of the product's quality. 16% of users were less impressed with the aesthetic appeal, feeling that the design was too plain or lacking distinctive features. Some users suggested that more vibrant color options or unique design elements could enhance the interface's visual presence. 84% Setup Process 80% of users found the setup process for the MOTU M4 straightforward and hassle-free. They appreciated the clear instructions and minimal steps required to get the interface up and running. The straightforward installation of drivers and software contributed to a smooth start for most users. 20% of users encountered challenges during the setup process, often related to driver installation or compatibility with their specific operating systems. Some users reported issues with outdated instructions or the need for manual troubleshooting to resolve initial setup problems. 80% Connectivity 81% of users were satisfied with the connectivity options of the MOTU M4, highlighting the versatile USB-C connection that provided stable data transfer. Users appreciated the convenience of a single cable for power and data, which simplified their setup and reduced cable clutter. 19% of users had issues with connectivity, primarily related to USB-C compatibility with older systems or the need for adapters. Some users experienced intermittent connection problems, which they attributed to cable quality or port compatibility issues. 81% Driver Stability 75% of users were pleased with the stability of the drivers provided with the MOTU M4, noting that they facilitated consistent and reliable performance across different applications. Users appreciated the regular updates and support from MOTU to maintain optimal driver functionality. 25% of users experienced driver stability issues, which impacted their usage of the interface. Some reported crashes or glitches during sessions, requiring frequent updates or reinstallations to resolve. Others found the drivers less stable on certain operating systems, leading to frustration. 75% User Interface 83% of users were satisfied with the user interface of the MOTU M4, praising its intuitive design and easy-to-navigate controls. Users found the interface straightforward, with clearly labeled inputs and outputs that simplified the recording process. 17% of users found the user interface lacking, mainly due to personal preferences or specific workflow needs. Some users desired more customizable options or advanced features that were not available with the current interface design. 83% Preamp Quality 89% of users were impressed with the preamp quality of the MOTU M4, noting the clean and transparent sound that enhanced their recordings. Users appreciated the low noise floor and ample headroom provided by the preamps, which allowed for detailed and dynamic audio capture. 11% of users were not satisfied with the preamp quality, often citing noise issues or insufficient gain for certain microphones. Some users found that the preamps did not perform as well as those in higher-end interfaces, though they acknowledged the trade-off for the price point. 89% Firmware Updates 77% of users appreciated the availability of firmware updates for the MOTU M4, which improved functionality and addressed common issues. Users valued the proactive approach taken by MOTU to enhance the interface's performance over time through updates. 23% of users were dissatisfied with the firmware update process, often due to difficulties in installation or lack of clear instructions. Some users experienced problems after updates, such as changes in settings or new bugs, which required further troubleshooting. 77% Overall Satisfaction 88% of users expressed overall satisfaction with the MOTU M4, praising its performance, build quality, and value. Users felt that it met or exceeded their expectations in most areas, making it a highly recommended choice for those seeking a reliable audio interface. 12% of users were not fully satisfied with their experience, often due to isolated issues with specific features or compatibility. While most found the product to be satisfactory, these users highlighted areas for improvement to enhance the overall user experience. 88% Metering Accuracy 84% of users were satisfied with the metering accuracy of the MOTU M4, noting the clear and precise visual feedback provided during recording and playback. Users appreciated the detailed meters that allowed for effective monitoring of audio levels. 16% of users encountered issues with metering accuracy, often related to discrepancies between the interface's meters and those in their DAW. Some users found the visual feedback less responsive or precise than expected, impacting their ability to accurately monitor levels. 84% Output Quality 90% of users were impressed with the output quality of the MOTU M4, highlighting its clear and detailed sound reproduction. Many users noted the high-quality headphone and line outputs, which provided accurate audio representation for mixing and monitoring. 10% of users were not satisfied with the output quality, often due to specific issues with their setup or preferences. Some users experienced faint noise or distortion, which they attributed to external factors or mismatched equipment rather than the interface itself. 90% Show More

User Rating Based on Analysis of Reviews

Purchase Value

87% of users found the MOTU M4 USB-C Audio Interface to be a great value for money, highlighting its competitive pricing compared to other interfaces with similar features. Many appreciated the high-quality preamps and low-latency performance, which are often found in more expensive models. Users noted that the interface provided excellent sound quality and a robust build, making it a worthwhile investment for both amateur and professional audio creators.

13% of users expressed dissatisfaction with the purchase value, feeling that the interface did not meet their expectations in terms of performance relative to its price. Some users encountered issues with the software or compatibility with certain operating systems, which they felt detracted from the overall value. Additionally, a few users mentioned that other brands offered similar features at a lower cost.

87%
Sound Quality

92% of users were highly satisfied with the sound quality provided by the MOTU M4. They praised its clear and transparent audio output, which significantly improved their recording and playback experience. Many users appreciated the pristine sound and the high-quality DA converters, which they felt allowed for professional-level recordings without colorization of the input signal.

8% of users were not satisfied with the sound quality, mainly due to individual preferences or specific issues with their setup. Some reported that the sound output did not meet their expectations for clarity or depth, which may be attributed to mismatched equipment or improper calibration. A few users experienced noise or interference that they believed was related to the interface.

92%
Build Quality

90% of users praised the MOTU M4 for its solid build quality. They appreciated the sturdy metal chassis, which provided durability and a premium feel. Many users noted that the interface could withstand the rigors of both studio use and on-the-go recording, and liked the high-quality knobs and buttons that enhanced the user experience.

10% of users were not satisfied with the build quality, citing issues such as loose knobs or buttons that felt flimsy. A few users experienced physical defects, such as poorly fitted parts or cosmetic damage. While these cases were relatively rare, they impacted the overall perception of the interface's durability for those affected.

90%
Ease of Use

85% of users found the MOTU M4 user-friendly, highlighting its straightforward setup process and intuitive controls. Many appreciated the clear labeling and layout of the interface, which made it easy to navigate without prior technical experience. Users felt that the accompanying software was well-designed and complemented the hardware effectively, adding to the convenience of use.

15% of users found the MOTU M4 challenging to use, often due to difficulties with the initial setup or software installation. Some users mentioned that the documentation was not detailed enough, requiring them to seek additional help online. Others experienced configuration issues with certain DAWs, which took time to troubleshoot and resolve.

85%
Software Compatibility

78% of users were satisfied with the software compatibility of the MOTU M4, reporting smooth integration with major digital audio workstations (DAWs) and operating systems. They appreciated the stable drivers and the ease of configuring the interface with their existing audio setups, which facilitated seamless recording and editing sessions.

22% of users encountered software compatibility issues, particularly with less common DAWs or older operating systems. Some reported driver instability or lag during sessions, which affected their workflow. A number of users also pointed out the lack of dedicated apps or support for mobile devices, limiting the interface's versatility for certain use cases.

78%
Latency Performance

91% of users were highly satisfied with the latency performance of the MOTU M4, noting its low-latency monitoring capabilities and efficient driver performance. This aspect was particularly praised by musicians and producers who require real-time audio feedback for recording and mixing, as it allowed them to work without noticeable delay.

9% of users experienced latency issues, which they attributed to their specific computer configurations or the need for additional optimization. Some users found that latency increased when using multiple plugins or high sample rates, which disrupted their workflow and required adjustments to mitigate.

91%
Customer Support

74% of users were satisfied with the customer support provided by MOTU, appreciating the responsive and helpful service they received when encountering issues with the M4. Many users found the support team knowledgeable and capable of resolving their problems efficiently, which increased their overall satisfaction with the product.

26% of users were dissatisfied with customer support, reporting slow response times and unhelpful resolutions to their inquiries. Some users felt that their issues were not adequately addressed, leading to prolonged downtime and frustration. A few also mentioned that the support resources available online were insufficient for troubleshooting their specific problems.

74%
Portability

89% of users appreciated the portability of the MOTU M4, noting its compact size and lightweight design. This made it easy to transport and ideal for mobile recording setups or small studio spaces. Users liked that it could easily fit into a backpack or gear bag, making it convenient for musicians and producers on the move.

11% of users found the portability of the MOTU M4 lacking, primarily due to the need for additional cables or power sources in certain setups. Some users mentioned that while the size was compact, the interface did not feel as rugged as other portable options, causing concern about potential damage during transport.

89%
Input/Output Options

82% of users were satisfied with the input/output options offered by the MOTU M4, highlighting the versatility provided by the combination of XLR, line, and MIDI inputs. Users enjoyed the ability to connect a range of instruments and devices, which made the interface suitable for various recording scenarios.

18% of users felt that the input/output options were limited, particularly for more complex audio setups. Some users desired additional inputs or outputs to accommodate larger sessions, while others found the lack of digital I/O options a drawback for integrating with certain studio equipment.

82%
Design

88% of users appreciated the design of the MOTU M4, praising its sleek, modern look and intuitive control layout. The interface's aesthetic appeal and practical design elements, such as the large volume knob and clear metering displays, were frequently mentioned as positive aspects that enhanced the user experience.

12% of users were not satisfied with the design, citing minor ergonomic issues such as cramped control spacing or less intuitive button placement. Some users felt that the visual design could be improved for easier navigation during sessions, particularly in low-light environments.

88%
Durability

86% of users were satisfied with the durability of the MOTU M4, noting its robust construction and resilience to wear and tear. Many users felt confident in its long-term performance, even with regular use in demanding environments. This aspect added to the perceived value and reliability of the interface.

14% of users expressed concerns about durability, often due to personal experiences with wear-related issues or defective units. Some users reported problems with connectors or components becoming loose over time, which affected their confidence in the interface's longevity.

86%
Aesthetic Appeal

84% of users were pleased with the aesthetic appeal of the MOTU M4, appreciating its sleek, understated design that blended well with other studio equipment. Users liked the clean lines and professional appearance, which contributed to a positive perception of the product's quality.

16% of users were less impressed with the aesthetic appeal, feeling that the design was too plain or lacking distinctive features. Some users suggested that more vibrant color options or unique design elements could enhance the interface's visual presence.

84%
Setup Process

80% of users found the setup process for the MOTU M4 straightforward and hassle-free. They appreciated the clear instructions and minimal steps required to get the interface up and running. The straightforward installation of drivers and software contributed to a smooth start for most users.

20% of users encountered challenges during the setup process, often related to driver installation or compatibility with their specific operating systems. Some users reported issues with outdated instructions or the need for manual troubleshooting to resolve initial setup problems.

80%
Connectivity

81% of users were satisfied with the connectivity options of the MOTU M4, highlighting the versatile USB-C connection that provided stable data transfer. Users appreciated the convenience of a single cable for power and data, which simplified their setup and reduced cable clutter.

19% of users had issues with connectivity, primarily related to USB-C compatibility with older systems or the need for adapters. Some users experienced intermittent connection problems, which they attributed to cable quality or port compatibility issues.

81%
Driver Stability

75% of users were pleased with the stability of the drivers provided with the MOTU M4, noting that they facilitated consistent and reliable performance across different applications. Users appreciated the regular updates and support from MOTU to maintain optimal driver functionality.

25% of users experienced driver stability issues, which impacted their usage of the interface. Some reported crashes or glitches during sessions, requiring frequent updates or reinstallations to resolve. Others found the drivers less stable on certain operating systems, leading to frustration.

75%
User Interface

83% of users were satisfied with the user interface of the MOTU M4, praising its intuitive design and easy-to-navigate controls. Users found the interface straightforward, with clearly labeled inputs and outputs that simplified the recording process.

17% of users found the user interface lacking, mainly due to personal preferences or specific workflow needs. Some users desired more customizable options or advanced features that were not available with the current interface design.

83%
Preamp Quality

89% of users were impressed with the preamp quality of the MOTU M4, noting the clean and transparent sound that enhanced their recordings. Users appreciated the low noise floor and ample headroom provided by the preamps, which allowed for detailed and dynamic audio capture.

11% of users were not satisfied with the preamp quality, often citing noise issues or insufficient gain for certain microphones. Some users found that the preamps did not perform as well as those in higher-end interfaces, though they acknowledged the trade-off for the price point.

89%
Firmware Updates

77% of users appreciated the availability of firmware updates for the MOTU M4, which improved functionality and addressed common issues. Users valued the proactive approach taken by MOTU to enhance the interface's performance over time through updates.

23% of users were dissatisfied with the firmware update process, often due to difficulties in installation or lack of clear instructions. Some users experienced problems after updates, such as changes in settings or new bugs, which required further troubleshooting.

77%
Overall Satisfaction

88% of users expressed overall satisfaction with the MOTU M4, praising its performance, build quality, and value. Users felt that it met or exceeded their expectations in most areas, making it a highly recommended choice for those seeking a reliable audio interface.

12% of users were not fully satisfied with their experience, often due to isolated issues with specific features or compatibility. While most found the product to be satisfactory, these users highlighted areas for improvement to enhance the overall user experience.

88%
Metering Accuracy

84% of users were satisfied with the metering accuracy of the MOTU M4, noting the clear and precise visual feedback provided during recording and playback. Users appreciated the detailed meters that allowed for effective monitoring of audio levels.

16% of users encountered issues with metering accuracy, often related to discrepancies between the interface's meters and those in their DAW. Some users found the visual feedback less responsive or precise than expected, impacting their ability to accurately monitor levels.

84%
Output Quality

90% of users were impressed with the output quality of the MOTU M4, highlighting its clear and detailed sound reproduction. Many users noted the high-quality headphone and line outputs, which provided accurate audio representation for mixing and monitoring.

10% of users were not satisfied with the output quality, often due to specific issues with their setup or preferences. Some users experienced faint noise or distortion, which they attributed to external factors or mismatched equipment rather than the interface itself.

90%

Pros:
	High-quality audio performance with ESS Sabre32 Ultra DAC technology. Ultra-low latency performance, making it suitable for real-time monitoring. Comprehensive metering with full-color LCD display for precise level monitoring. USB-C connectivity ensures fast data transfer and compatibility with modern devices. Sturdy build quality and compact design, ideal for portable use. Loopback functionality for easy live streaming and podcasting.

Pros:

High-quality audio performance with ESS Sabre32 Ultra DAC technology.
Ultra-low latency performance, making it suitable for real-time monitoring.
Comprehensive metering with full-color LCD display for precise level monitoring.
USB-C connectivity ensures fast data transfer and compatibility with modern devices.
Sturdy build quality and compact design, ideal for portable use.
Loopback functionality for easy live streaming and podcasting.

Cons:
	Limited to 4 inputs and 4 outputs, which may not be sufficient for larger setups. No built-in DSP effects, which could limit flexibility for some users. Only USB bus-powered, which might not be ideal for all scenarios. No ADAT or S/PDIF connectivity, limiting expansion options.

Key Specs
Channels of I/O
Analog: 4 Inputs / 4 Outputs	Analog: 4 Inputs / 4 Outputs
Maximum Sampling Rate
192 kHz / 24-Bit	192 kHz / 24-Bit
Number of Microphone Inputs
2 Preamps	2 Preamps
Analog Audio I/O
2x Combo XLR-1/4" TRS Balanced/Unbalanced Mic/Line/Hi-Z Input (Front Panel) 2x 1/4" TRS Balanced Line Input 2x 1/4" TRS Balanced Monitor Output 1x 1/4" TRS Unbalanced Headphone Output (Front Panel)	2x Combo XLR-1/4" TRS Balanced/Unbalanced Mic/Line/Hi-Z Input 2x 1/4" TRS Balanced Line Input 1x 1/4" TRS Unbalanced Headphone Output 4x 1/4" TRS Balanced Line Output (DC-Coupled) 4x RCA TS Unbalanced Line Output
Host Connection
1x USB-C	1x USB-C
OS Compatibility
macOS 10.14 or Later Windows 10	macOS 10.11 or Later Windows 7 or Later 9 or Later
Power Requirements
AC/DC Power Adapter (Included) or USB Bus Power	USB Bus Power

The MOTU M4 USB-C Audio-MIDI Interface and Universal Audio Volt 4 Portable 4x4 USB Audio/MIDI Interface both offer a range of professional features tailored for different audio production needs, with several key similarities and differences.
In terms of Channels of I/O, both interfaces provide 4 analog inputs and 4 outputs, making them suitable for multi-track recording and playback. The maximum sampling rate for both devices is 192 kHz at 24-bit, ensuring high-quality audio resolution.
Both interfaces also feature 2 microphone inputs with preamps, providing ample capability for capturing vocals or instruments with high fidelity. For analog audio I/O, the MOTU M4 includes 2 combo XLR-1/4" TRS inputs for mic/line/Hi-Z sources, 2 additional 1/4" TRS balanced line inputs, a 1/4" TRS unbalanced headphone output, 4 balanced 1/4" TRS line outputs (DC-coupled), and 4 RCA TS unbalanced line outputs. Conversely, the Universal Audio Volt 4 has 2 combo XLR-1/4" TRS inputs (front panel), 2 balanced 1/4" TRS line inputs, 2 balanced 1/4" TRS monitor outputs, and a 1/4" TRS unbalanced headphone output on the front panel.
For host connection, both interfaces use a USB-C connection, ensuring fast data transfer and compatibility with modern computers.
When it comes to OS compatibility, the MOTU M4 supports macOS 10.11 or later and Windows 7 or later, providing a broader range of compatibility. The Universal Audio Volt 4 supports macOS 10.14 or later and Windows 10, catering to more recent operating systems.
Power requirements differ slightly between the two interfaces. The MOTU M4 is powered solely via USB bus power, making it highly portable and convenient for mobile setups. The Universal Audio Volt 4 can be powered either through an included AC/DC power adapter or via USB bus power, offering flexibility depending on the user's power availability and preferences.
In summary, both the MOTU M4 and Universal Audio Volt 4 are capable USB audio interfaces with high-quality audio resolution, multiple inputs and outputs, and flexible power options. The choice between them may come down to specific needs such as operating system compatibility, power preferences, and the desired configuration of analog audio I/O.

General
Channels of I/O
Analog: 4 Inputs / 4 Outputs	Analog: 4 Inputs / 4 Outputs
Maximum Sampling Rate
192 kHz / 24-Bit	192 kHz / 24-Bit
Number of Microphone Inputs
2 Preamps	2 Preamps
Input Level Adjustment
2x Knob	2x Knob
Expansion Slots

The MOTU M4 USB-C Audio-MIDI Interface and the Universal Audio Volt 4 Portable 4x4 USB Audio/MIDI Interface share several key features, making them comparable options for users seeking a 4x4 audio interface.
Both the MOTU M4 and the Universal Audio Volt 4 offer 4 analog inputs and 4 analog outputs, providing ample connectivity for various audio sources and destinations. Each interface supports a maximum sampling rate of 192 kHz at a bit depth of 24-bit, ensuring high-resolution audio quality for professional recording and playback.
In terms of microphone inputs, both interfaces are equipped with 2 preamps, allowing users to connect and record high-quality audio from microphones. Additionally, both the MOTU M4 and the Universal Audio Volt 4 feature input level adjustment with 2 knobs, offering precise control over input gain.
Neither the MOTU M4 nor the Universal Audio Volt 4 includes expansion slots, indicating that they are designed as standalone units without the capability for internal upgrades. Similarly, neither interface has a built-in microphone, focusing instead on providing high-quality preamps for external microphones.
A notable difference between the two is that the Universal Audio Volt 4 does not have built-in DSP (Digital Signal Processing), while the MOTU M4 does not specifically mention DSP capabilities. This could be an important consideration for users who require onboard processing features for effects and signal enhancement.
Overall, both the MOTU M4 and the Universal Audio Volt 4 are robust 4x4 USB audio interfaces with high-resolution audio support, making them suitable for a variety of recording and production needs.

Connectivity
Analog Audio I/O
2x Combo XLR-1/4" TRS Balanced/Unbalanced Mic/Line/Hi-Z Input (Front Panel) 2x 1/4" TRS Balanced Line Input 2x 1/4" TRS Balanced Monitor Output 1x 1/4" TRS Unbalanced Headphone Output (Front Panel)	2x Combo XLR-1/4" TRS Balanced/Unbalanced Mic/Line/Hi-Z Input 2x 1/4" TRS Balanced Line Input 1x 1/4" TRS Unbalanced Headphone Output 4x 1/4" TRS Balanced Line Output (DC-Coupled) 4x RCA TS Unbalanced Line Output
Phantom Power
48 V, Selectable On/Off (Applied to All Inputs)	48 V, Selectable On/Off (Selectable on Individual Inputs)
Digital Audio I/O

Host Connection
1x USB-C	1x USB-C
Host Connection Protocol
USB 2.0	USB 2.0
MIDI I/O
1x DIN 5-Pin Input 1x DIN 5-Pin Output	1x DIN 5-Pin Input 1x DIN 5-Pin Output

The MOTU M4 USB-C Audio-MIDI Interface and the Universal Audio Volt 4 Portable 4x4 USB Audio/MIDI Interface both offer robust options for audio recording and MIDI connectivity, but they differ in several key aspects.
Starting with the analog audio I/O, both interfaces provide 2x Combo XLR-1/4" TRS inputs that support balanced/unbalanced mic, line, and Hi-Z inputs. The MOTU M4 extends its flexibility with an additional 2x 1/4" TRS balanced line inputs, making it suitable for connecting extra line-level devices. In contrast, the Universal Audio Volt 4 includes 2x 1/4" TRS balanced line inputs but offers fewer output options than the MOTU M4. Specifically, the MOTU M4 features 4x 1/4" TRS balanced line outputs (DC-Coupled) and 4x RCA TS unbalanced line outputs, while the Volt 4 provides 2x 1/4" TRS balanced monitor outputs. Both units include a 1/4" TRS unbalanced headphone output.
Regarding phantom power, the MOTU M4 and the Universal Audio Volt 4 both offer 48V phantom power. However, the MOTU M4 allows for selective phantom power on individual inputs, giving users greater control over their input configurations. On the other hand, the Volt 4 applies phantom power uniformly to all inputs, which might be less flexible in certain recording scenarios.
Both interfaces lack digital audio I/O and have a single USB-C host connection that uses the USB 2.0 protocol. Neither device includes additional USB (non-host), sync I/O, or network I/O capabilities.
In terms of MIDI connectivity, both the MOTU M4 and the Universal Audio Volt 4 feature 1x DIN 5-pin input and 1x DIN 5-pin output, enabling integration with a variety of MIDI gear.
In summary, while both the MOTU M4 and Universal Audio Volt 4 are capable and versatile audio-MIDI interfaces, the MOTU M4 offers more analog output options and selective phantom power, making it potentially more flexible for complex recording setups. The Universal Audio Volt 4, however, provides essential features and might appeal to users looking for a straightforward, high-quality interface.

Digital Audio
Sample Rates
Up to 192 kHz	Up to 192 kHz
Sample Rate Conversion

Bit Depths
24-Bit	24-Bit
Latency
Zero-Latency Direct Monitoring	Zero-Latency Direct Monitoring2.5 ms at 96 kHz (Dependent on Buffer Size, Input to Output)
Sync Sources
Internal	Internal

The MOTU M4 USB-C Audio-MIDI Interface and the Universal Audio Volt 4 Portable 4x4 USB Audio/MIDI Interface share several core features, making them both robust choices for audio recording and production.
Both interfaces support sample rates up to 192 kHz, ensuring high-resolution audio recording and playback. This allows users to capture and reproduce audio with exceptional detail and clarity. Neither device offers sample rate conversion, indicating that they both rely on the host computer or other equipment to manage any necessary conversions.
In terms of bit depth, both interfaces operate at 24-bit, providing a wide dynamic range and reducing the potential for quantization noise. This bit depth is standard for professional audio interfaces, ensuring that both the MOTU M4 and the Universal Audio Volt 4 can deliver high-quality recordings.
Latency is a critical factor for real-time audio monitoring. The MOTU M4 offers zero-latency direct monitoring and reports an impressive latency of 2.5 ms at 96 kHz, dependent on buffer size and input to output configuration. The Universal Audio Volt 4 also provides zero-latency direct monitoring, although specific latency figures are not detailed in the specifications provided. This feature in both devices is crucial for performers and producers who require real-time feedback without delay.
Both interfaces use internal sync sources, meaning they generate their own timing information to ensure stable and accurate audio performance. This is a standard feature for interfaces in this category, ensuring reliable operation without the need for external synchronization.
In summary, the MOTU M4 USB-C Audio-MIDI Interface and the Universal Audio Volt 4 Portable 4x4 USB Audio/MIDI Interface are comparable in terms of sample rate, bit depth, latency, and sync sources. Both devices offer high-quality, professional-grade audio recording capabilities, making them suitable choices for a variety of audio production needs.

Audio Storage & Playback
Memory Card Slot

When comparing the MOTU M4 USB-C Audio-MIDI Interface and the Universal Audio Volt 4 Portable 4x4 USB Audio/MIDI Interface, one striking similarity is the absence of a memory card slot in both devices. This omission is noteworthy as it reflects a design choice focused on direct interfacing with computers or other recording setups rather than standalone recording capabilities.
Both interfaces are designed with USB connectivity in mind, allowing for seamless integration with modern digital audio workstations (DAWs) and other recording environments. The lack of memory card slots in both models means that users will need to rely on their connected devices for data storage and management, which is standard for many contemporary audio interfaces aimed at professional and semi-professional users.
This similarity simplifies the decision-making process for potential buyers who might be concerned about onboard storage options, as neither the MOTU M4 nor the Universal Audio Volt 4 offers this feature. Instead, the focus for both interfaces remains on providing high-quality audio input and output, robust connectivity options, and reliable performance in a variety of recording and production scenarios.

Compatibility
OS Compatibility
macOS 10.14 or Later Windows 10	macOS 10.11 or Later Windows 7 or Later 9 or Later
Processor Requirement
Mac: Intel Apple M1 Intel AMD	Mac: 1 GHz Intel PC: 1 GHz Intel Pentium
Required Hardware
Available USB 2.0 Port USB Cable (Included)	Available USB 2.0 Port USB Cable (Included)
Internet Connection
Required for Registration, Software/Driver Download	Required for Software/Driver Download

The MOTU M4 USB-C Audio-MIDI Interface and the Universal Audio Volt 4 Portable 4x4 USB Audio/MIDI Interface are both competitive in the realm of audio interfaces, each bringing unique features to the table.
OS Compatibility: The MOTU M4 is compatible with macOS 10.11 or later and Windows 7 or later. On the other hand, the Universal Audio Volt 4 supports macOS starting from 10.14 and Windows 10. The broader Windows compatibility of the MOTU M4 might appeal to users with older systems, while the Volt 4’s focus on more recent operating systems might ensure better integration with newer features.
Processor Requirement: For the processor requirements, the MOTU M4 requires a 1 GHz Intel processor for both Mac and PC systems. The Universal Audio Volt 4 is more versatile in this area, supporting Intel and Apple M1 processors for Mac, as well as Intel and AMD processors for Windows, which might indicate better performance with a wider range of hardware.
RAM Requirements: The MOTU M4 requires a minimum of 2 GB of RAM, with 4 GB recommended. The Universal Audio Volt 4 specifications do not explicitly mention RAM requirements, but it can be inferred that it will be compatible with systems adhering to the OS requirements stated.
Required Hardware: Both interfaces require an available USB 2.0 port and include a USB cable. This makes them equally accessible in terms of basic hardware setup, ensuring that users can get started right out of the box.
Internet Connection: Both the MOTU M4 and Universal Audio Volt 4 require an internet connection for software or driver downloads. However, the Volt 4 also specifically mentions the need for an internet connection for registration.
Mobile Device Compatibility: The Universal Audio Volt 4 stands out by offering compatibility with mobile devices such as the iPad Pro, iPad, and iPhone. This feature makes it particularly attractive for users looking to integrate their audio interface with mobile workflows.
In summary, the MOTU M4 offers broader OS compatibility, particularly for older Windows systems, with straightforward hardware and RAM requirements. The Universal Audio Volt 4, while requiring newer operating systems, provides greater processor flexibility and notable mobile device compatibility, catering to a more modern and versatile user base.

Power
Power Requirements
AC/DC Power Adapter (Included) or USB Bus Power	USB Bus Power

When comparing the MOTU M4 USB-C Audio-MIDI Interface and the Universal Audio Volt 4 Portable 4x4 USB Audio/MIDI Interface based on power requirements, there are notable differences. The MOTU M4 is designed to operate solely on USB bus power, which means it draws the necessary power directly from the connected USB port of the host device, such as a computer. This simplifies the setup process by eliminating the need for an external power supply, making it a convenient and portable option for users who require a straightforward, single-connection interface.
In contrast, the Universal Audio Volt 4 offers more flexibility in terms of power options. It can operate using USB bus power, similar to the MOTU M4, but it also includes the capability to be powered via an AC/DC power adapter. This dual power option means that users can opt to connect the interface to an external power source (5 VDC) if additional power stability or headroom is needed, which can be particularly useful in studio settings where consistent power supply is crucial. The AC/DC power adapter is included with the device, providing an added layer of convenience for users who might need it.
In summary, the MOTU M4’s power requirement of USB bus power makes it a highly portable and straightforward option, whereas the Universal Audio Volt 4’s dual power options – USB bus power or an AC/DC power adapter – offer increased flexibility and potential for more stable performance in various settings.

Physical
Anti-Theft Features
Kensington Security Slot	Kensington Security Slot

The MOTU M4 USB-C Audio-MIDI Interface and the Universal Audio Volt 4 Portable 4x4 USB Audio/MIDI Interface are both equipped with anti-theft features, specifically a Kensington Security Slot. This feature aids in securing the devices against theft, making them suitable for use in public or shared spaces.
In terms of dimensions, the MOTU M4 measures 8.25 x 4.25 x 1.75 inches (20.96 x 10.79 x 4.45 cm) for the chassis only, which provides a compact and portable form factor. The Universal Audio Volt 4 does not have specified dimensions in the provided data, so size comparisons cannot be directly made.
Regarding weight, the MOTU M4 weighs 1.6 lb (0.7 kg), making it lightweight and easy to transport. The weight for the Universal Audio Volt 4 is not specified, so a direct comparison in this aspect is not possible.
In summary, both the MOTU M4 and the Universal Audio Volt 4 have anti-theft features with the inclusion of a Kensington Security Slot. The MOTU M4 is detailed with specific dimensions and weight, making it clear that it is a portable and compact device, whereas similar detailed physical specifications for the Universal Audio Volt 4 are not provided in the given data.

Packaging Info
Package Weight
3.225 lb	2.15 lb
Box Dimensions (LxWxH)
9.8 x 8.7 x 5.3"	10.6 x 7.3 x 2.8"

The MOTU M4 USB-C Audio-MIDI Interface and the Universal Audio Volt 4 Portable 4x4 USB Audio/MIDI Interface differ in terms of weight and box dimensions, which could influence portability and storage considerations for users.
The MOTU M4 USB-C Audio-MIDI Interface has a package weight of 2.15 lb and its box dimensions are 10.6 x 7.3 x 2.8 inches. This makes the MOTU M4 relatively lightweight and compact, potentially offering easier portability and less space requirement for storage. Its slimmer profile could be advantageous for users who need to transport their audio interface frequently or have limited desk space.
In contrast, the Universal Audio Volt 4 Portable 4x4 USB Audio/MIDI Interface has a package weight of 3.225 lb, making it heavier than the MOTU M4 by approximately 1.075 lb. The box dimensions for the Universal Audio Volt 4 are 9.8 x 8.7 x 5.3 inches. While slightly smaller in length, it is wider and significantly taller than the MOTU M4. This larger and heavier package might suggest a more robust build or additional components but could also mean it is less convenient to carry around and requires more storage space.
In summary, the MOTU M4 is lighter and more compact, which may be beneficial for users prioritizing portability and minimal desk space usage. The Universal Audio Volt 4, while heavier and bulkier, might offer other benefits not covered in this comparison, but from a purely physical standpoint, it is less portable and requires more storage space.