Review: Shure MVX2U dockable USB audio interface for XLR mics with limiter + much more by Allan Tépper

The ultracompact MVX2U has several advantages not found in other multiplatform inline interfaces I have covered previously.

Allan Tépper

August 15, 2023

Comment

(UPDATED) Today Shure unveiled the MVX2U (U$129), a very powerful inline dockable USB interface for analog XLR microphones of any type (condenser, dynamic or even ribbon -after deactivating the 48-volt phantom power, since it ships active), which transforms them into high quality digital USB mics, with built-in latency-free monitoring, as well as optional effects including compressor, limiter and EQ (equalization). Unlike many other inline XLR-to-USB interfaces I have covered previously, the new MVX2U features several important advantages. Ahead, I’ll share those advantages, specs, pricing, my opinions, as well as test recordings with one of the most gain-hungry dynamic mics in the world, the SM7B, compared with the same mic connected to the Zoom F3 (U$350). I also tested the MVX2U with the Saramonic SR-HM7 handheld dynamic mic.

Specific advantages in the MVX2U

The following are specific advantages in the MVX2U compared to other inline multi-platform interfaces (i.e. the iRig Pre HD) I have tested and reviewed in the past. I am excluding the RØDE iXLR (reviewed in 2016) since it was limited only with devices that use the Lightning port and did not offer phantom power, only bias voltage, aka “plugin power”.

The manufacturer is actually willing to state the maximum gain in dB, and it’s officially 60dB of clean gain.
Dockable to a microphone without a coupler (previously, this required the iRig Pre HD to add an XLR coupler to make it dock to a mic) as covered in more detail ahead.
Selectable limiter (very good, tested ahead)
Selectable dynamic compression: off, light, medium, heavy (very good, tested ahead)
Variable EQ (not tested)
Selectable automatic gain control (see comments in the appropriate section)

Acknowledgements

The MVX2U was sent to me by Shure under a non-disclosure agreement for testing prior to the announcement, in order to publish the review the day of the announcement.

The Shure SM7B was lent to me by Elite Music Studios for this and other tests and reviews.

Although Saramonic has provided other models for review, the Saramonic SR-HM7 model used in this test was purchased by me with my own funds.

Dockable versus inline (MVX2U does either)

Review: Shure MVX2U dockable USB audio interface for XLR mics with limiter + much more 2

In the past, in order to dock an inline interface like the iRig Pre HD, it was necessary to acquire and use an XLR coupler, as I covered in Directly attach iRig Pre HD to an ENG omni dynamic mic (illustrated above). Fortunately, the MVX2U is capable of being connected either docked or inline. Docking can be achieved with any handheld XLR microphone, and with nearly any studio microphone. However, some flexible booms (including the RØDE PSA1+ ) may prevent it with the SM7B. In that case, you can connect the MVX2U inline instead of docked.

Review: Shure MVX2U dockable USB audio interface for XLR mics with limiter + much more 3

In the above photo, the Saramonic SR-HM7 dynamic cardioid handheld microphone is docked to the MVX2U.

What comes in the box

MVX2U Digital Audio Interface
a 1m USB-C to USB-C cable
a printed quick-start guide

Common factors with all test recordings

All recordings were made at our standard 48 kHz sampling rate. Because the two microphones used in the test are dynamic, I had the 48-volt phantom power deactivated. I have no doubt that the selectable 48-volt phantom power will work fine, when required.

The recordings made via the Shure MVX2U were made at 48 kHz/24-bit in uncompressed WAV in Hindenburg Pro. They were trimmed and normalized before publication in uncompressed mono WAV at 48 kHz/24-bit.

The comparison recordings made on the Zoom F3 were made at 48 kHz/32-bit float (32-bit float is currently the only option with the F3). They were trimmed and normalized before publication in uncompressed mono WAV at 48 kHz/24-bit.

Both DIP switches in the SM7B with A7WS were set to flat mode for all tests.

Normalization was done, section by section. However, no EQ (equalization) or noise reduction was performed.

Audio tests to determine cleanliness and transparency

Above, SM7B with A7WS recorded via MVX2U. The MVX2U was set to manual gain at 60dB, since the SM7B required all of it to achieve a proper recording. Compression and equalization were inactive in the MVX2U.

Above, comparison recording of the same SM7B with A7WS recorded via the Zoom F3.

Above, Saramonic SR-HM7 (published sensitivity: 52.4 dB) recorded via MVX2U. The MVX2U was set to manual gain at 52dB. Compression and equalization were inactive in the MVX2U.

Above, comparison recording of the same Saramonic SR-HM7 recorded via the Zoom F3.

MY TAKE ON THIS SECTION:
In this mode, the MVX2U fulfills Shure’s offering of having sufficient gain even for the SM7B. In addition, to my ears, it sounds very clean and transparent. I find it slightly different from the one made with the Zoom F3, but not better or worse. Of course, the F3 is also a standalone recorder, in addition to being an interface (with preamps and A-to-D conversion). I am impressed with the performance of both devices. If you hear any differences, please comment below.

Audio test of MVX2U dynamic compressor

The above recording was made with the SM7B and A7WS with manual gain set to 60dB. The recording progressively tests compressor inactive, mild compression, medium compression and heavy compression.

MY TAKE ON THIS SECTION:
All sounded as they should. For most content, I would use mild or medium compression. I would only use heavy compression for a short promo or 30-second radio spot.

Audio test of MVX2U remote mute function

The above recording was made with the SM7B and A7WS with manual gain set to 60dB. The remote is currently accessible (to my knowledge) only from the ShurePlus MOTIV desktop app.

MY TAKE ON THIS SECTION:
The mute function sounded very clean, without any audible click. I reiterate my previous request to Shure to add a keyboard shortcut for muting to the Shure MOTIV desktop app.

Audio test of MVX2U limiter function

I applaud Shure for including a hardware-based limiter in the MVX2U. This feature prevents overmodulation or clipping if and when an unexpected much higher volume (i.e loud laugh or scream) is experienced during a recording or live broadcast. The last time I saw this rare feature in an interface was back in 2014 with the now discontinued Tascam iXJ2 (review here), and the Tascam iXJ2 was not suitable for balanced XLR mics, but unbalanced TRS mics and was for Lightning only. The last time I saw this rare feature in a microphone was in 2017 with the now discontinued Sennheiser HandMic Digital (reviewed here).

MY TAKE ON THIS SECTION:
In my testing, the MVX2U indeed has a hardware-based limiter which works even without being actively connected to the ShurePlus MOTIV desktop app. As with the other DSP functions, the software is only to assign the settings in the hardware. Then the MVX2U hardware works independently of the software, as it should.

Audio test of MVX2U AGC (automatic gain control)-UPDATED

The above recording was made with the SM7B and A7WS in automatic gain mode, “Close”. The above recording is the new version, after a firmware update to version 1.1.0.388 released later in the day on 2023-08-05 which improved the AGC quality. Be sure to update your firmware to the latest version.

MY TAKE ON THIS SECTION:
This doesn’t sound as good as the prior recordings made with manual gain. However, it works adequately for situations where manual control is not feasible. If possible, it’s better to set levels manually, but whenever that is not feasible. the AGC is great to have.

3.5 TRS headphone jack for latency-free monitoring-UPDATED

After the 1.1.0.388 firmware, I retested the MVX2U’s 3.5 TRS headphone jack for latency-free monitoring using two different pairs of headphones, both with 32Ω impedance (fairly low). They were the RØDE NTH-100 (reviewed here) and the Maono AU-MH601 (reviewed here).

MY TAKE ON THIS SECTION:

After the 1.1.0.388 firmware update released later in the day on 2023-08-15, there is plenty of available volume. What I hear is clean and latency free to my ears. Please keep in mind that beyond the balance between the microphone sound heard for the headphones and the playback from the host computer, which we can set in the ShurePlus MOTIV desktop app, the headphone volume for the MVX2U’s headphone output must be set in the host computer’s volume after setting the computer to monitor to the MVX2U. This volume control on the host computer continues to adjust the volume level of the MVX2U’s headphone output even when the ShurePlus MOTIV desktop app is not active.

Platform compatibility

According to Shure, the MVX2U is for macOS and Windows. I did my testing on macOS. So far, Shure has not mentioned whether the MVX2U will work properly with Android, iOS or iPadOS. I will update this article or publish another if I hear of any change.