BlitzWolf BW-BR4 Bluetooth Transmitter Review

Blizwolf audio streaming device
BlizWolf Audio Streaming Device

BlitzWolf BW-BR4 Bluetooth transmitter Review & Specfication

Building the perfect audio system to stream music from Spotify can be very challenging, especially if you are trying to design a very cost-effective device. Now, this is when things get more interesting. My idea is to use a low-cost SBC (Single Board Computer) connected to the BlitzWolf BW-BR4 audio Bluetooth adapter that was kindly provided to me by Banggood for this semi review semi hands-on guide.

Product Introduction

The BlitzWolf BW-BR4 device can function both as a receiver and transmitter device and can best be connected with external speakers. It comes in a compact small size case, measuring 85.2 x 80.8 x 23.1mm. It uses Bluetooth 5.0 Lossless Transmission with an external antenna, assuring Stable signal, long transmission distance (up to 100m), intelligently compatible with 99% of devices Pure copper gold-plated terminals to strengthen the stability and accuracy of audio transmission signal Proper size and attractive appearance.

It supports multiple inputs interfaces (3.5mm AUX, SPDIF Input/Output, RCA). The Micro USB port located on the rear side used to charge the unit internal 3.7V 600mAh battery via a standard 5V power adapter, making it very portable and easy to use inside a car. As mentioned previously, the device can operate in TX/RX (Transmite / Receiver) modes with a switch of a button located on the backside of the device.

A Limited Time Offer on Banggood Store!

BlitzWolf W-BR4

Final Price: $27.99

Blitzwolf BW-BR4


Package Content (Unboxing)

From left to right:

  • 1x BR4 bluetooth Transmitter & Receiver
  • 1x User Manual
  • 1x Service Contact Card
  • 1x Fiber Optic Cable(100cm)
  • 1x 3.5mm Audio Cable(60cm)
  • 1x Micro USB Charging Cable(85cm)
  • 1x 3.5mm to RCA Cable(26cm)

Build Quality & Design

BW-BR4 comes in an elegant case with an excellent clean design made from a high-quality plastic material. It consists of a grey metallic-like surface with a very glossy upper cover in black color that can leave finger smudges.

Operation Modes – Transmitter & Receiver

The BW-BR4 comes with a TX/RX switch located on the rear side of the device. It allows you to select from Transmit/TX mode (for sending audio from a wired jack to your headphones) to Receive/RX mode (for sending music or directions wirelessly from your iPhone to a car’s AUX IN or to the AUX IN of a non-Bluetooth speaker).

Receiver mode (RX)

In receiver mode, when the BW-BR4 unit is hooked to external speakers, its capable of receiving a stream from a portable mobile device, for example, from a smartphone or tablet PC.

Because the unit rechargeable with an internal 600mAh battery, you can also use it inside a car. Pair your car Bluetooth system with the BW-BR4 and stream music to external speakers.

Transmite mode (RX)

In transmitter mode, you can connect the BW-BR4 unit to any audio source and stream the audio directly to a Bluetooth appliance device. This function is very useful if you have a home audio system and you need wireless connectivity to stream and listen to music via headphones. Connecting to Bluetooth speakers is also a good option, if you have a pair you can position theme in few spots inside a room and enjoy a great surround effect without using any use of cables.

BC8675 Bluetooth Chip

The BC8675 chip gives you Bluetooth V5.0 and optical audio output for a truly universal wireless solution.

Stable Transmission

164ft Wireless Connection Range
Built-in antenna, up to 50 meters (164ft) long-range and stable transmission to share your audio from indoors to outdoors.

Optical Fiber Transmit

It gives you the option of a digital connection to your playback device for maximum audio quality.

Long Standby Time

With a built-in 600mAh battery, you get up to 17 hours working time and 175 hours standby time. 

Double simultaneous connections

The BlitzWolf BW-BR4 device is capable of double connections. This means that two devices can be connected simultaneously via Bluetooth connection. This can be used for example watching television via two headphones to keep things quiet for, for example, sleeping children, or connecting two Bluetooth speakers to have music from different sources in the house from the same source.


Bluetooth VersionV5.0
InterfaceMicro USB(5V Charging), 3.5mm AUX, SPDIF Input/Output, RCA
Chipset SolutionCSR BC8675
Operation RangeClass I, 100 meters
Bluetooth ProfileA2DP, AVRCP
Audio codingTX: aptX™ HD, aptX™ low latency, aptX™, SBC
RX: aptX™ HD, aptX™ low latency, aptX™, AAC, SBC
Battery Capacity3.7V 600mAh
Charging TimeAbout 2.5 hours
Standby TimeRX mode: About 175 hours
Working TimeAUX – About 15 hours
SPDIF – About 17 hours
Operating Temperature-10—55℃
Net Weight 111.2g
Size 85.2 x 80.8 x 23.1mm

Use Case #1: Send audio to your car speaker

According to power requirement printed on the bottom of the unit, to charge the BW-BR4 unit you will need to use a 5V 0.5A power adapter (not included in the package). To avoid any future problems damaging the device, if you don’t have a 0.5A in reach, we advise sticking with maximum 1A adapter with a standard Micro USB plug.

When you will need to charge the unit, you would probably need to use the car USB socket if available . If you don’t have on, you can use a charger connected to the car cigarette lighter socket.

Use Case #2: Send audio to your Bluetooth headphone

In this type configuration you can use the BW-BR4 to input audio from a source appliance, such as a home media center and pair with a Bluetooth headphone to listen to music.

Use Case #3: Send audio from your SBC

Building a home Audio system

The Project Objective is to build a super low-cost audio system composed of the BlitzWolf BW-BR4 and a cheap SBC (Single board computer) running android or any Debian based distribution.

The needed accessories/items need for this project to work are listed in the following table:

        Item No'


     Item Photo


      Buy Links


 BlitzWolf BW BR4 

Blizwolf audio streaming device 2



  NanoPi K1 Plus

K1 plus



A2-A2 Ribbon Flat HDMI Cable. L=15CM

Flat ribbon hdmi cable



5 inch 800*480 TFT LCD Display

52pi raspberry pi 3 5inch screen stand


Please note that you can choose almost any SBC with an AUX or HDMI interface. For this one, we picked the FriendlyElec NanoPi K1 Plus board that has both of them. If you don’t need the comfort of using a display, you can reduce additional extra costs from the system overall price by buying a board without an HDMI port.

If you are looking for a more elegant solution with a built-in display. You should consider buying all in one kit that offers a plastic enclosure with a built-in 3.5-inch display that should be enough to display general functions when playing music. If you prefer to mount the SBC externally, you can buy a larger 5 up to 7-inch display desperately and mount it behind a frame housing bracket.

Setup & configuration:

  • Enabling the BlitzWolf BW-BR4 in TX mode.
  • Plugging the BlitzWolf BW-BR4 to the SBC Audio jack using the coax extension stereo cable.
  • Downloading nanopi-k1-plus_eflasher_friendlycore-xxxx image.
  • Burning image file to eMMC or Micro SD Card using the ‘Etcher‘ Tool.
  • Installing Xfce Desktop environment: apt update & apt install xfce4
  • Running Xfce: startx
  • Set the output through the headphone jack interface by editing the configuration file:

sudo nano /etc/asound.conf

Changing the card interface to ‘Card 1‘ (Audio jack).

Installing Spotify for Linux & Radio Tray

That’s It! Now you are ready to pair your Bluetooth speaker/headphone with the BW-BR4 device and listen to your favorite music.

Optional Configurations (Source: AliExpress)

Configuration#1: (Raspberry Pi Board is not included)

Item DescriptionQTYBuy Link
7-inch Display1
Display Housing Bracket1

Configuration#2: (Raspberry Pi Board is not included)

Item DescriptionQTYBuy Link
Full Kit (Case + 3.5 inches TFT Display)1

Use Case #4: Send audio from your Smartphone (RX)

The most popular option is probably streaming audio via smartphone from popular streaming services such as YouTube, Spotify, Deezer, live radio stations, and so forth.

To connect your speakers, you will need to use the RCA Extension cable or a stereo headphone plug to connect to the AUX port. For this type of configuration, we use a pair of old/used speakers with an impedance of 6-ohms (each). Just keep in mind that this arrangement worked well, but if you need a higher volume boost, it’s best that connect the BlitzWolf BW-BR4 to a suitable hi-fi system equipped with an amplifier.


In my test, when pairing a Huawei P20 smartphone to a pair of 6 ohms speakers (each) without an amplifier, the volume level is not very high. To overcome this problem, and override manufacturer default volume levels presets in your phone, I highly recommended installing a volume boost app such as ‘Volume Booster Pro.’

Streaming audio from a mobile phone to a pair of wired speakers.

Sound Quality

From my general impression, the BlitzWolf BW-BR4 provided excellent clear sound. The AUX port is also very comfortable if you want to connect with a 3.5 mm headphone plug. If you are seeking maximum sound quality at higher volume levels, I recommend connecting your BW-BR4 through coaxial or optical cable directly into an amplifier.


In my test, the BlitzWolf BW-BR4 device preformed well with no interferences when placed in a nearby room with open doors at a distance of about 4 meters.

Charging Time

To power the BW-BR4 device you can connect it to a standard a USB port of a PC television, or a car.

Battery Operation/Life

The battery life of the BlitzWolf BW-BR4 was impressive. For such a small device, with a 600mAh battery inside its capable of lasting up to 175 hours on standby mode. In real-world situations, you can expect it to work in both RX/TX modes trough AUX and SPDIF interfaces for about 15-17 hours.

Final Words

Defiantly a well-designed product with top-notch audio quality I highly recommend buying.

BlitzWolf BW-BR4 Review Summary


Build Quality
Battery Time
Sound Quality
Value for Money


An excellent worth buying product!

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