1MiiB03Pro Bluetooth 5.3 Transmitter Receiver for Home Stereo TV, HiFi Wireless Audio Adapter with Audiophile DAC & AptX HD/Low Latency, Long Range, Optical RCA AUX 3.5mm Outputs/Inputs

I’ve been working at home during the pandemic and got tired of always having earphones in so I dug an old Panasonic compact stereo out of the basement to set up on my desk. Well, the audiophile bug I’ve had off-and-on for 40 years bit again and the kit speakers soon proved unsatisfactory, so I started upgrading my system. The most important component in any audio system is the speakers, and I picked up a used, vintage pair of Monitor Audio MA 301s, which I think are probably the finest small bookshelf speaker under $1000 ever made. I was using a little Mpow BT receiver to play Spotify through my iPhone, but figured I could get much better sound quality with something that was bigger and more substantial than a device that was smaller than a pack of gum.I tend to over-research everything electronics before I commit, and was very impressed by several reviews I’ve seen of another Bluetooth DAC (digital-to-analog converter - it’s what turns digital signals into analog audio that can be played through an amplifier to speakers or headphones, and most people into high-quality music will have either a standalone DAC or a high quality one in their CD player or amp/preamp) sold here on Amazon for only 25 bucks. It’s made by a company called Mypin and got rave reviews from several audio review channels on YouTube that stated in addition to Bluetooth, it would also improve the audio quality if connected to a CD player, compared to the player’s built in DAC. So I bought the little Mypin, but also spotted this 1Mii unit that boasted an “audiophile DAC” plus also receives better-than-CD Apt-X HD signals and pretty much all other high-quality Bluetooth audio signal types. And so I figured I would give this one a try too, as I could always send it back if it wasn’t notably better than the $25 Mypin.Since we are wedded to a family Spotify plan, and Spotify won’t have lossless, cd quality audio available until some later point in 2021, I also started thinking I wanted to be able to play a lot of my old CDs to be able to have better sound quality than through the Bluetooth and decided to pick up an used Sony five disc carousel CD/DVD/SACD player to use as a transport and run its digital signal into the Bluetooth DAC unit to let the DAC convert the signal to analog (also, my amplifier has only a single pair of RCA auxiliary inputs, so I would be able to use the BT DAC as an audio switch between the Bluetooth receiver and the DAC unit processing sound from my CDs). So I needed a DAC that had a traditional digital audio input, either a coaxial one or an optical one. There are a number of audiophile Bluetooth DAC receivers on Amazon in the $100-$180 range (iFi Zen Blue, Bluedento, Audioengine B1), that have the highly regarded Burr Brown DAC chip in them but surprisingly their coaxial and optical digital connections are for output only to another DAC which makes little sense - Why equip a device with a high-quality DAC that works only for Bluetooth rather than any other digital connections? The Mypin has both coaxial and optical inputs, but the 1Mii has only one optical input; it does have a digital optical output, too, I guess if you have a higher and stand alone DAC and just want to use this unit for the Bluetooth.So my Amazon package with the two Bluetooth DAC’s arrives and I try out the cheaper one first. The Mypin did have better sound than my Mpow portable BT receiver playing Spotify and had slightly better sound than connecting the CD player directly.Then I tried the 1Mii B03Pro+..First thing to note is that unlike any of the more audiophile specific BT DAC’s or even the cheap $25 Mypin one, this unit does not have standard RCA outputs to run a pair of RCA interconnects into one’s amplifier or receiver. Instead there is only a standard 3.5 mm headphone-size output jack. Luckily, I had a 3.5 mm to RCA cable, plus there is one included in the box, but the included cable is very thin, very cheap, and has sound quality commensurate with its appearance. I replace the included one with the relatively inexpensive cable I have used to plug old cell phones into my AV receivers for several years and noted an immediate and very appreciable increase in sound quality, but with some buzzing and feedback in Bluetooth mode, unless the cable was adjusted just right in the back of the 1Mii unit.The B03Pro+ (the “Pro+” means that it has the audiofile DAC) features an ESS Sabre DAC, which I recall vaguely hearing of before, but I did some further research. I noted some audio industry news stating this DAC was being used in an LG cell phone, which initially did not have me very impressed, until I learned that model LG is generally recognized as having the finest sound quality of any cell phone. A bit further research revealed highly-regarded entry-to-mid level audiophile brands Arcam, Audioquest, Cambridge Audio and NAD use the same DAC chip in some of their standalone DAC units, as well as in amplifiers and cd players.So how does it sound? So good that I put the $25 unit back in the box and haven’t given any thought of using that but may give it to someone else. I have found a good test of a system’s sound quality is how it reproduces Mighty Sam McLain’s vocals – – a cheaper system leaves his voice a bit thin whereas a higher quality one renders his voice deep, rich, and perhaps the finest male vocalist in the blues genre. The B03Pro+ does full and proper justice to McLain’s voice.I think the area where this DAC also makes the biggest impact is with soundstage and imaging. With the signal coming straight from the CD player, sound for most recordings is mostly coming identifiably from each speaker and its range is only between the two speakers. When I connected this DAC between the CD transport and the amplifier, the speakers simply disappeared. The soundstage in some recordings expanded far outside of the speakers and certain instruments or singers were precisely positioned at a location between the speakers, sometimes much higher than the level of the speaker. Using Dire Straits’ Private Investigations, one can precisely hear and visualize just where the eerie cat is crying, where the wine glass breaks, and follow the footsteps as they walk across the entire soundstage.The Bluetooth audio is also quite good, but my source is limited, not just by Spotify’s sub-CD quality, for the present, but by my iPhone 7’s Bluetooth- I didn’t realize it at the time, but Apple doesn’t use the highest quality BT transmission- Apt-X HD, which is available for some Android phone users. I haven’t used the unit as a transmitter, for instance, plugged into a television so that one could use Bluetooth headphones to listen. However, as a receiver, it has scary long range. If I want to watch some thing on my phone when I go to bed and I have forgotten to shut the 1Mii off at night, it will play the audio through the Bluetooth DAC instead of my phone, even from across the house. And this is one of its biggest negatives: although it paired very easily with my iPhone and automatically repairs with it when switched to Bluetooth mode, it does not want to disconnect. I either have to forget the device altogether on my phone or go downstairs and shut off the unit, otherwise it will reconnect to my phone, which is mildly annoying.I got a bit annoyed with the buzzing sound that sometimes happens when the cable isn’t precisely adjusted in the 3.5 mm jack in Bluetooth mode, so I bought a better 3.5mm-to-RCA cable, an Audioquest Evergreen. I am only a limited believer in the benefits of audiophile cables and wires, and don’t think that anything above the $50 range typically would produce a notably better sound that could repeatably be detected in a blind listening test by the vast majority of people. However, I did notice a significant improvement in the sound using the Audioquest cable, not merely that the buzzing and feedback had disappeared. On the Cowboy Junkies’ beautifully recorded The Trinity Session CD one can hear subtle breaths by Margo Timmons in her soft but beautiful voice. Her brother Michael’s outstanding (and under-appreciated) guitar work is also improved with more detail. The Audioquest cable is a recommended accessory- the 3.5mm-to-RCA cable that 1Mii includes in the box does not do justice to the audiophile capabilities of this DAC.In conclusion, I am really enjoying high quality music again right on my office desk and this 1Mii Bluetooth DAC is a big part of it. I highly recommend this unit and even if one rarely would use the Bluetooth functionality, it is a very solid value at about 75 bucks just to use as a standalone DAC.

First thing I will say is that I already own a earlier version of the model 1Mii B03 and can vouch for the excellent customer / technical support I received in the past. When there was a question depending on the time of day the email was sent sometimes I received an answer back within a few hours. So customer support gets an A+ right off the bat. As a former Product Design Engineer one of the first things I look for is attention to detail and quality. And although it may not have any effect whatsoever on the operation of a particular product. Sometimes the packaging will give one a little insight into what to expect if that attention is carried all the way through to the final product. So from the moment I received this unit I was very impressed at how well it was packaged. There was a quick start guide immediately visible upon opening of the carton with well written and clear instructions. The new Hi Fi version B03 Pro also has attention to details designed into it along with a quality look and feel as did its predecessor. The included full-size multi language manual is also well written, clear, & concise with lots of diagrams to assist in setting up the unit depending on how it is to be connected. The B03 Pro comes with everything required to install and connect it to a TV, or stereo receiver including the B03 Pro transmitter / receiver, power adapter, USB charging cable, optical cable, 3.5 mm audio cable, & a 3.5 mm to RCA cable. Syncing the Bluetooth worked flawlessly with my old and new iDevices in the receiver mode. Nor did I have any problem syncing to my Bluetooth headphones in the transmitter mode. I connected the B03 Pro to my Yamaha A1000 receiver, and to be perfectly honest was not expecting to be able to discern any appreciable sound quality difference from my older unit. Much to my pleasant surprise the new Pro version was significantly better in sound quality. The dynamic range from highs to low was nothing short of astounding! As was the sound when the B03 Pro was transmitting to my headphones as well. Overall I give this unit A++ for sound quality, ease of setup & syncing, price point value, looks and functionality. I can honestly highly recommend the B03 Pro to anyone who is a audiophile with a discerning ear for Hi Fi sound. You will not be disappointed.

Just set this up the other day to pair with some Herdio outdoor speakers I installed on my back deck. I bought this to connect to the zone 2 pre out on my Denon DRA800H AVR in my living room, about 50 feet away from the speakers through an exterior facing wall. Connected via RCA plugs, powered it on, and it immediately paired with the speakers. I was listening to zone 2 audio within a minute. Like I said, the range is excellent as the transmitter is indoors, about 50 feet away from the speakers.I don't use the volume controls on the transmitter, as my phone (via the Denon HEOS app) can control the volume, which is great, as I've seen other reviews complaining that they have to use the transmitter to control volume. Not with my setup!The only complaint I have is that there is no display on the unit to help you determine what bluetooth device you want to connect to. I think I just got lucky that it 'chose' my outdoor speakers right off the bat.

At first I thought this would only work with head phones and a sound bar if you wanted tow outputs. Some how after I connected and paired the OneOdio 70 headphones I was able to listen on the head phones but the TV was muted. I connected an sound bar and both worked. Switched to bypass and TV sound came on. Switched back to tx and both the TV and the headphones worked. If I did something else , I don't know what it was. I am impressed that every time I turn on the headphones the connection is automatic. This works flawlessly.