xDuoo offers a couple of Bluetooth add-on modules (05BL and 05BL Pro) that insert into the rear panel of their flagship line of portable DAC/amps (XD-05, XD-05 Basic, and XD-05 Plus). For under USD $60, the 05BL Pro is an update of the previous (non-Pro) model. While physically very similar, the Pro version updates the internal chipset and resolves many of the connection issues plaguing the first version, and adds additional Bluetooth connection codecs for improved audio quality. The 05BL Pro is a bit bulky and adds length to the (already fairly large) XD-05 while covering up the charge and analog output ports. It is definitely a compromise compared to a portable device with an internal Bluetooth implementation. I’ve had the XD-05 Plus on hand for quite a while now, and I tend to use it more for desktop duty than for portable usage as it’s a bit overpowered for most IEMs. My daily go-to for portable use is the Chord Mojo. While the Mojo is a fantastic portable DAC/amp, it has no internal Bluetooth support, and the suggested Chord Poly wireless add-on device is bulky and prohibitively expensive (about 10x the price of the 05BL Pro). So, it was with great interest that I stumbled across a YouTube video earlier this year by Michael Bruce. In it, he showed how the 05BL Pro can plug into the Mojo. Can the inexpensive xDuoo Bluetooth add-on act as a Poly replacement? Is it really that easy? This review will cover two topics, using the 05BL Pro with the XD-05 Plus (as intended) and how to use (and modify) the 05BL for pairing with the Mojo.
Where to Buy
XDuoo Company Overview
The Shenzhen xDuoo Technology Co., Ltd. is located in Shenzhen China, and (according to their website) have served as an ODM for many well-known brands and companies for several years. XDuoo focuses on headphone audio products including portable and desktop DACs, amplifiers, Bluetooth modules, DAPs, and interconnection cables. They claim that “the total number of products designed is more than 100 models, and we have a number of patented technologies that can meet the needs of users.”
Specifications
Name: 05BL Plus Brand: xDuoo Price: $58 Form: Add-on Bluetooth Module Bluetooth Chip: CSR8675 Range: 10 meters Removable Cable: USB C Bluetooth Audio Codec: SBC, AAC, APTX, APTX LL, APTX HD, LDAC Battery Life (hours): Charging Time (hours): 2 Bluetooth Version: 5 Mic: cVc Noise Cancelling
Packaging
The xDuoo company knows a thing or two about attractive and supremely functional packaging. The diminutive 05BL Pro is no exception, with a printed white cardboard outer box, slide open internal box, and the goodies all securely nestled in snug-fitting cutouts. The packaging is just as nice for this sub-$60 item as it is from their higher-priced products.
In the box
xDuoo continues to wow me with their included accessories. Other companies might just toss their Bluetooth dongle in a bag and call it a day. xDuoo includes a (much appreciated) USB C charging cable and they go above and beyond by throwing in a sculpted aluminum volume knob protector for the XD-05 devices, replacement screws, and a tool for installation! This illustrates xDuoo’s commitment to, and their understanding of, their lineup of XD-05 DAC/amps. Users are buying the 05BL Pro to make their XD-05 device more portable. However, a big issue with using the XD-05 as a pocket device is that the protruding knob can be easily accidentally turned, and the extreme output power of these devices make them (potentially) dangerous to use with efficient IEMs. xDuoo to the rescue! Four black screws and a perfectly formed volume knob protector make accidental volume changes far less likely. Including the proper tool for the job is the icing on the cake. Well done xDuoo. Thank you for thinking of your customers!
Design
The 05BL Pro is clearly designed to match the shape and aesthetics of the XD-05 devices. It’s rounded, flared, and flat where it needs to be, in order to be flush with the XD-05 when connected. The rear surface is an interesting raised checkerboard pattern that is reasonably attractive. The 05BL Pro is made of black plastic, rather than aluminum like the XD-05, which likely is to facilitate Bluetooth reception and minimize weight. The buttons (along the top surface) are smaller than necessary and would benefit from being slightly larger for ease of use, although this might lead to accidental pocket presses. From left to right you will find the power/play/pause button, USB C charge port, power/connection LED, microphone, and back/forward buttons. Connections are simply two 3.5mm plugs that insert securely into the Aux In/Out and Digital In ports on the rear of the XD-05. Only the plug labeled Coaxial is actually functional. The other plug is just a dummy to provide structural support for the connection and is a clever and elegant connection solution. My primary complaint with the design of the 05BL Pro is that when connected, it covers the rear ports and indicators on the XD-05. This means you can’t plug in the charging cable to the XD-05, which essentially eliminates the Bluetooth module as a viable desktop option. Unfortunately plugging the USB C cable into the 05BL Pro does not pass along charging to the XD-05. Both devices must be charged separately.
Bluetooth Function
To test Bluetooth range, I used my tried and true approach of leaving my phone in the middle of my smallish house and roaming around with the device being tested. The Bluetooth connection worked as well as expected, and I only experienced dropouts when behind doors, walls or floors. xDuoo claims 10 meters of open-air range, and this seems likely reasonably accurate. In most cases, the 05BL Pro should work fine in the same room as your phone or computer.
Internals
The original 05BL sported the CSR8670 chipset, while the Pro uses the newer CSR8675. Both chips are rated for Bluetooth 5, however, the Pro now supports AptX-LL, AptX-HD, and LDAC Bluetooth codecs. These higher-quality connections bring a big audio upgrade over the older model. The microphone in the BL05 Pro supports Qualcomm’s cVc noise cancellation technology. Qualcomm claims that “cVc noise cancellation technology brings advanced audio enhancements and noise suppression to the near and far end, and provides packet loss and bit error concealment. In combination, this delivers the best possible call quality on Bluetooth headsets, handsets, hands-free devices, and automotive communication devices.” In practice, the microphone seems to work as it should.
Sound
Connected with one of the higher quality Bluetooth Codecs, the sound quality of the 05BL Pro is very good indeed. Most importantly, unless extremely critically listening, it is virtually indistinguishable from a wired connection. Some folks will never be a Bluetooth believer, but codec advances have really come a long way in minimizing the difference between wired and wireless. Unless using extremely resolving gear in a very quiet environment, I’d be surprised if the 05BL Pro will not satisfy most listeners. Bluetooth’s sheer convenience for on the go usage has more than won me over.
Using the 05BL with the Chord Mojo
You can use the 05BL with the Chord Mojo straight out of the box with no modifications necessary. Simply plug the coaxial digital output plug into the socket labeled ‘COAX’ on the Mojo and you are done. Due to the second plug on the 05BL Pro, the orientation will need to be strangely canted at an odd angle to fit. Never being one to leave good enough alone, I eyed the included screw tool and noted that it fits the four screws holding the 05BL together. A minute or so later, I popped off the cover and found that the extra plug was, in fact, a dummy and held on only with an internal nut. Simply unscrew this nut and it pops right out. Success! I used a foam stick-on bumper to fill the newly uncovered hole in the 05BL. By removing the dummy plug, the 05BL can be better lined up with the body of the Mojo. It also allows the 05BL Pro to be rotated in and out of position (while still maintaining connection) to access the sockets on both the Mojo and the XD-05. It’s still not a perfect match to the Mojo but isn’t too out of place. Functionally, the 05BL Pro works just as well with the Mojo as it does with the XD-05. The sound is clean and surprisingly high fidelity. For a Bluetooth Poly replacement at less than 1/10 of the price, I’ll take it!
xDuoo 05BL vs 05BL Pro Comparison
Conclusion
I love this little device. If you want to add Bluetooth wireless functionality to either your XD-05 device and/or to the Chord Mojo, the 05BL Pro is a must-buy! Make sure you are getting the Pro version as the functionality and sound quality is much improved over the original model (at almost the same price). Using the included tool and spending 5 minutes removing the dummy plug was a worthwhile modification for me, however, be aware that this is entirely optional. The 05BL Pro will work perfectly with the Mojo (and of course the XD-05 family of devices) right out of the box. Low cost, good build quality, great sound quality and it works as advertised (and for purposes not advertised)! It’s almost a must-buy for XD-05 owners simply for the volume knob cover, even if you never use the 05BL Pro itself. What more could you want?
