General

How does the Subwoofer 4 compare to the Subwoofer 3?

The Subwoofer 4 has all-new electronics with Bluetooth designed to pair and work perfectly with the Minirig 4. The analogue crossover in the Subwoofer 3 has been replaced with advanced digital audio processing. The result is deeper, cleaner and more powerful bass—perfectly complementing the Minirig 4 at all volume levels.

In addition, it now has USB-C with fast charging and an 18W power bank feature. Volume controls on the Subwoofer allow you to adjust bass levels and pair with the Minirig 4 easily over Bluetooth.

Finally, using the Minirig app, you can tweak the sound of the Subwoofer 4 and keep it updated with the latest features.

Why do I need a subwoofer?

The Minirig 4 on its own has powerful sound with great bass, but is limited by the physics of its size. The Subwoofer 4 produces much more bass output and digs much deeper, down to 38Hz. It also benefits from placement on the floor or in a corner, which boosts low frequencies even more.

Most full-range Bluetooth speakers of this size can’t match the deep bass levels of the Minirig Subwoofer 4. With it, you hear and feel the full sound range of your music.

Can I use the Subwoofer 4 on its own?

No. On its own, you will only hear bass. You need to use it with a Minirig 4 or other full-range Minirig speaker. It can also work with other speakers, with variable results.

Will it work with the Minirig 3 and older products?

Yes, but not via Bluetooth. They do not communicate wirelessly. They are designed to be in-phase, so they will sound great when connected using cables. The best method is to Bluetooth to the Sub 4 and then use AUX out to the Minirig 3. See the how-to guide for more info.

It will work with all products via AUX. You’ll need to adjust the Subwoofer 4 volume to balance levels.

Will it work with the Minirig Subwoofer 3?

Yes—either in AUX-in mode or Bluetooth mode with AUX output. See our how-to guide for details.

Can I use it with other speakers?

Yes, but only if the other speaker can connect via cable. You can Bluetooth to the Subwoofer 4 and use AUX out, or connect both via cables. Results may vary depending on the other speaker’s phase response.

Can I pair to it?

Yes. Please see the how-to guide for pairing instructions.

How do I reset the Minirig Subwoofer 4?

1. Turn the Minirig Subwoofer 4 on.
2. Press and hold the power button for 6 seconds.
3. The unit will begin turning off and the LEDs will illuminate red.
4. Release the power button.
5. After a few seconds, the power LED will illuminate yellow and the 4-LED bar will show a yellow loading cycle.
6. After ~10 seconds, it will finish resetting and turn off.

You can now use it normally. You must pair again.

How many Minirig 4s and Subwoofer 4s can you link together?

You can link two Minirigs for wireless stereo (left/right) or one Minirig and one Subwoofer 4 for mono (L+R). Using linkup mode, you can link as many as you like and manually adjust balance and volume to form your soundstage.

Can I use it for DJing?

Yes. The Subwoofer 4 can connect to DJ equipment or any analogue-output device via 3.5mm AUX. Latency is only ~2ms—similar to placing a speaker 70cm away.

Can I trade in my Minirig Subwoofer 3?

The trade-in scheme only applies to the oldest products when parts are no longer available. If your Minirigs are working, it’s best to keep them—you can link them via audio cables.

Charging

How fast does the Minirig Subwoofer 4 charge?

Using a USB-C to USB-A cable (“legacy”), charging is limited to 900mA (4.5W) and takes about 6 hours.

To charge faster, use USB-C to USB-C and an 18W USB-C PD charger—this gives a full charge in under 1.5 hours.

Is the battery life better than the Subwoofer 3?

The Subwoofer 4 delivers more power and deeper bass at max output, so battery life at full volume is slightly less. In general use, battery life is similar to the Subwoofer 3.

How much power does it provide as a power bank?

33Wh—enough for 1–2 phone charges, depending on the phone.

Sound

Does placement matter?

Yes. Bass increases when the Subwoofer is near boundaries. On the floor and/or near a wall is louder. The loudest position is a corner, though this may cause boominess.

For the best sound, keep the Subwoofer the same distance from you as the Minirig 4.

Room size also affects sound—smaller rooms may be more bassy or boomy, and certain notes may resonate.

Is it louder than the Subwoofer 3?

The Subwoofer 4 has slightly more power and offers much more controlled excursion and cleaner limiting—up to 20dB more output at 38Hz.

In AUX mode, the Subwoofer 3 had higher gain, so you may need to increase AUX gain on the Subwoofer 4 via the app to match it.

Bluetooth

Does the Minirig 4 have aptX or LDAC?

No—but aptX only works with specific hardware that is no longer used, and offers minimal real-world improvement. LDAC could have been licensed, but testing showed it unnecessary. LDAC works only on some Android devices, doesn’t support wireless stereo/link-up modes, and often drops to 330kbps, which can sound worse.

SBC/AAC quality is now very good with modern devices. If worried about sound quality, first increase the streaming quality in your music app (many default to 96kbps). For high-res files, you can use AUX, though this introduces one extra ADC/DAC step.

The differences between codecs are marginal—speaker quality and placement matter far more.

*aptX and LDAC are not available on iOS devices.

Does it have good Bluetooth range?

Yes. Range is ~50% greater than the Minirig 4, up to 80m outdoors. Raising the product improves range but is not ideal for bass output.

App

How can I get the app?

A new, simplified app is available on Google Play, the Apple App Store, Chrome browsers (PC/Mac), and as a downloadable APK.

The app supports the Minirig Subwoofer 4—check for updates and support pages.

Do you plan to add support for more operating systems and browsers?

The APK works on Android systems without Play Store. The web app works on any browser supporting the Web Bluetooth API.

Linux Chrome support is behind a flag: enable-experimental-web-platform-features. While not officially supported, it can work:

1. Connect to the Minirig in the OS first.
2. Use the grey “request device” button.
3. Select MRBT4APP (or MRBT4 BL when updating).

If issues persist, contact support with app version, browser, OS, screenshots, and details.

How do I update my Minirig Subwoofer 4?

1. Turn on the Subwoofer 4 and open the app.
2. Select “MINIRIG SUB 4” from the device list.
3. Open settings (top right).
4. Scroll to “SOFTWARE VERSION”.
5. Press “check for updates”.
6. If an update is available, press “update”.
7. The Subwoofer enters bootloader mode (yellow power LED).
8. Search for devices and select “MINIRIG SUB 4 UPDATER” or “MRS4 BL”.
9. Press “PROGRAM”.
10. Wait 2–3 minutes—do not leave the app.
11. The Subwoofer reboots (yellow loading cycle) then turns off.

It is now ready to use. You must pair again with your devices.