The iBasso CF01 is a Bluetooth receiver that can turn your ordinary IEMs (in-ear monitors) into TWS earphones. It has aptX and wireless charging support and has over 24 hours of battery life. There are other products out there that do the same thing but the CF01 has some features that I think makes it stand out from the rest. Let’s check it out in more detail.
Disclaimer: This sample was provided for the purpose of an honest review. All observations and opinions here are my own based on my experience with the product.
Supports wireless charging
Case can fit large IEMs
For MMCX IEMs only (can use 2-pin IEMs with an adapter)
No onboard volume control
Moderate battery life
Package and Accessories
The iBasso CF01 comes in a flip-top black box with an outer white cardboard sleeve. On the front of the sleeve is a colour image of the Bluetooth modules and lists some of the features. The back of the sleeve has another image of the modules and the case plus a list of specifications.
Inside the box, you get the charging case, CF01 modules, USB Type-C cable for charging plus a warranty card and user manual.
Design & Functionality
The CF01 modules are a bit smaller than the average USB flash drive. They’re constructed from black and silver-coloured plastic and are very lightweight. On top of each unit is a physical multi-function button for playback and call controls. There’s also a small LED indicator located within the buttons that display pairing and connection status.
The buttons function like any TWS earbud controls via a series of short and long presses but unfortunately, there is no onboard volume control. I found the buttons responsive and easy to use. Connected to each module is a short flexible cable terminating in an MMCX connector.
With an IPX5 rating, the CF01 modules can withstand sweat and moderate rainfall which is a real bonus. The overall build quality feels great.
It’s the charging/storage case that really sets the CF01 apart from other similar products. The first thing you’re likely to notice about it is that it’s pretty big. While that may seem like a deterrent initially, it’s actually that way for a good reason. We’ll get to that in a second. Let’s check out the other features of the case first.
It’s made of matte black plastic and feels really lightweight. On the back, there’s a USB Type-C port for charging while on the front is the opening mechanism (otherwise known as a button) and a small red LED which indicates the battery’s charging status. By the way, the iBasso CF01 case supports wireless charging too, which is pretty huge if you’re into that.
Inside is where the case really gets interesting. Both sides plus the underside of the lid all have a silicone pillow which protects your IEMs while they’re in the case. And yes, you can leave your IEMs connected to the Bluetooth modules and fit them into the case (hence why the case is so large). I even tested storing some of my largest IEMs in the case and they fit in easily.
Bluetooth Performance & Battery Life
In my testing, I found the stability and ease of use of the Bluetooth connectivity to be practically flawless. Pairing is a breeze and after the initial pairing with a source, the CF01 will automatically connect to the last known device as soon as you pull them from the case.
At the heart of the CF01’s operations is the Qualcomm QCC3020 Bluetooth Audio SoC. The Bluetooth range of the CF01 is fantastic and I can move more than 10 meters away before the signal begins to stutter. Latency during videos and games is excellent: there are no noticeable delay or sync issues when watching videos or YouTube. Even playing competitive first-person shooters on my iPhone I didn’t notice any latency whatsoever.
The CF01 has a lithium polymer battery that can be charged via the USB Type-C port or with a wireless charger. Playback time for the CF01 modules is around 4-4.5 hours which is a bit less than I’d expect for something of this size. Having said that though, the power output of the CF01 is pretty impressive and it can driver multi-driver IEMs with ease. The charging case will provide roughly another 4 full charges, delivering around 20 hours playtime in total.
I was limited to testing with AAC on my iPhone but I found it to perform really well regardless. To test with aptX, I paired up the CF01 with my Shanling M5s and FiiO M6. For IEM pairing, I chose a few of my preferred MMCX equipped models and found the performance to be consistent with each one.
In general, the CF01 has a neutral and transparent sound and what you hear will mostly depend on which IEM you hook up to it. I did notice that the sub-bass seemed to be slightly attenuated but the midrange and treble seemed mostly unaffected.
With the CF01, the midrange sounds transparent, detailed and nuanced. I found it to sound especially good on the IT00 which has a pretty hefty bass: the slight bass attenuation on the CF01 brings the mids slightly more forward.
Furthermore, I found the treble to sound a little more forward than usual too, generating a very detailed but slightly brighter sound. I was happy to discover that the soundstage is not diminished with the CF01. On the contrary, the soundstage is actually quite wide with good forward reach and imaging remains intact.
So in the end, you might not get quite the same performance as you do with wires but the CF01 comes very, very close indeed. The big takeaway here though is that you can make your existing earphones (which sound better than any TWS set) wireless without really losing any tangible audio quality.
TRN BT20s Pro ($69)
Coming in at just under half the price, the TRN BT20s Pro makes for a compelling alternative to the CF01. It uses the same Qualcomm QCC3020 chip, has swappable connectors and significantly better battery life.
It even has the same Bluetooth codec support (aptX, SBC, AAC) as the CF01. In terms of sound quality, I couldn’t even pick a winner if I’m being completely honest; they both sound exceptional and I would say each performs on par with the other in this aspect.
So why would you choose the CF01 over the BT20s Pro? Well, there are a few reasons. But whether they are worth paying twice as much for will be up to you. First of all, there have been some claims of poor build quality with the (previous) TRN Bluetooth modules. I can’t speak for the earlier models but I will say that my BT20s Pro is still in perfect working condition to this day.
The second reason why you might want the CF01 is that it offers better protection for your IEMs. Both charging cases can hold large earphones but the upper half of the TRN case is soft and offers little protection for your IEMs. In some cases, you might also need to detach the earphones from the TRN modules to make everything fit snugly into the case. On the other hand, the CF01 case has a more spacious interior, in addition to the case being rigid and having the protective silicone “pillows” inside.
The final advantage of the iBasso CF01 that comes to mind is its wireless charging support. For people who are already using wireless charging, this could be a major selling point for you.
The iBasso CF01 is a sterling example of the wireless options we audiophiles have at our disposal today. Sure, it may cost more than the alternatives but at this time, it offers superior protection for expensive IEMs and wireless charging.
It has a detailed, transparent sound, aptX support and flawless Bluetooth connectivity. If you’re looking to convert your high-end in-ear monitors to TWS then this could be exactly what you need.