Hi-fi streamers have always been a bugbear for me. You either get brilliant hardware with dreadful software, or great software with rubbish hardware. You can pay a few pounds for something that works but is missing features, or spend ludicrous money on a raspberry pi in a fancy box with some audiophile marketing and an established ‘audiophile’ name on the front. There are a couple of mediocre options that sit somewhere in the middle. Streaming and consumer audio are advancing faster than ever, leaving traditional hi-fi lagging far behind. And while I don’t expect the majority of hi-fi manufacturers to catch up, there are a few old dogs learning new tricks, and some promising new kids on the block.
One of the latter is WiiM. The company sprang up from nowhere with the WiiM Mini, a sub-£100 hi-fi streamer that people across the internet were raving about. They then brought out the WiiM Pro, adding a few extra features to a similar platform but still with a very reasonable price. We now have the Pro Plus and the WiiM Amp which integrates the WiiM streaming platform into a compact 60W per channel amplifier. I have the Pro Plus for this review so we will focus on it, but the WiiM App is the same across all WiiM devices.
The Pro and Pro Plus differs in their internal DAC. The Pro uses the Texas Instruments PCM5121 giving a 106dB signal to noise ratio and -92dB (0.0025%) total harmonic distortion reference the 2V RMS line level output. The Pro Plus uses the AKM 4493SEQ, giving a 121dB signal to noise ratio and -113dB (0.00023%) total harmonic distortion. It also has a better clocking circuit and improvements in the power supplies.
The WiiM Mini, Pro and Pro Plus all provide an analogue input to stream analogue sources across the network, limited to 16-bit 48kHz on the Mini and Pro and supporting up to 24-bit, 192kHz streaming on the Pro Plus.
Google Chromecast Audio is offered on the Pro and Pro Plus, as is support for grouping with Nest smart home speakers and the Nest display. The Pro and Pro Plus are also required to work with Google Voice, though all three devices support Siri and Alexa. All three can be grouped with echo speakers and Echo smart displays, all three can be grouped with Apple HomePods and all three can be grouped with other WiiM or or other brands of device that use the LinkPlay software. All three support AirPlay 2, but only the Pro and Pro Plus support AirPlay Cast and Alexa Multiroom with UHD.
DLNA, Spotify Connect, Tidal Connect, Qobuz (with autoplay), TuneIn, Pandora, Deezer, vTuner, Amazon Music, SoundCloud, iHeartRadio, Radio Paradise Calm Radio Napster, Sound Machine and Amazon Alexa are all supported. Naturally you also get DLNA support, and streaming from personal cloud storage such as Dropbox and Google Drive is said to be on the horizon. The WiiM streamer are also Roon Ready. And WiiM recently added SqueezeLite support to the Pro and Pro Plus, so they can interoperate with old Logitech Squeezebox devices, or a Raspberry Pi running PiCore Player.
Sadly there is no native support for Apple Music within the WiiM app. Apple Music subscribers will need to use AirPlay to stream Apple Music content. Native support would be nice to see, though it’s probably a limitation of Apple’s extortionate licensing. To my knowledge, only Sonos has a native Apple Music implementation and it is limited, more of which later.
No matter though. The WiiM streamers support AirPlay 2 and are fully HomeKit compliant. Adding your WiiM streamers to the home app is a matter of a few taps, at which point Siri can be used to quickly stream Apple Music content. Not an ideal solution perhaps, especially given that Siri is the dumbest smart assistant going, but it works.
And if you’re not in the Apple ecosystem, other integrations are possible. There are already multiple open-source home assistant integrations and a comprehensive (and very well documented) API over HTTP for integration into any control or automation system you can think of.
The Pro (and Pro Plus) is a neat little box, 5.5 inches (140 mm) square and 1.6 inches (42 mm) high with radiuses corners. It reminds me of the first-generation Mac mini, albeit slightly smaller and encased in plastic. Along the front are a row of capacitive touch controls for play / pause volume up / down and a single preset. These can be disabled within the app. There is also a status LED which changes colour and flashes at varying speeds to indicate the status of various functions including boot, firmware upgrade, input source, network and Bluetooth.
On the back are RCA analogue inputs and outputs. On the pro the latter supports up to 32-bit, 384kHz PCM, while the Pro Plus goes all the way up to 768K PCM and DSD512. There is an optical input, which like the analogue line input can be used to stream audio across the network or to a Bluetooth device at up to 24-bit, 192kHz. There are digital outputs on both S/PDIF optical and RCA coaxial, both supporting 24-bit 192kHz PCM. You even get good quality analogue RCA and digital optical cables in the box! There is no means of getting 32-bit, 384K (or 768K) PCs to your external DAC via USB, nor a means to connect a USB storage device or CD drive to the WiiM streamer. A couple of USB ports would have been the icing on a very tasty cake.
That said, anything beyond 24-bit, 192kHz audio doesn’t really matter in consumer audio anyway. Hell 26/44.1 CD quality audio has enough headroom to sample up to 22kHz, which is 2kHz above the supposed limit of human hearing. This ‘high-res’ thing isn’t all it’s cracked up to be. High-resolution audio has its place for sure, but a lot of the high-res audio sold to audiophiles is nothing more than marketing. Some of it is even upsampled 16-bit, 44.1kHz audio mastered for Cd. And in some case, they don’t bother upsampling the audio either so you’re buying a ripped CD, usually at several times the price. And as far as MQA, for which the WiiM Pro and Pro Plus do have partial support, let’s not even go there. It’s unclear what ‘partial’ support means exactly. But as MQA is less valuable even than fake high-res, and just another license to print money,I really don’t care and neither should you.
If you want to use your preferred DAC, the WiiM streamer have a trick up their sleeves – bit-perfect digital outputs. This means that the digital data is transmitted unaltered to your DAC. Many streamers with digital outputs still apply processing to the digital data, often some form of upsampling or on-device decoding. The data you get out of the WiiM’s digital output is a perfect representation of the data you fed in, so these are ideal streaming transports.
To that end there is a 12V trigger port, which (as of the latest update) will trigger when music starts playing or when the WiiM is brought out of standby via the remote, and deactivate after 5 minutes of inactivity. This can be used to power up a supported amplifier or hi-fi system by waking up the WiiM Pro or Pro Plus. It’s a handy feature, though the obvious limitation in that there is no way to adjust the system volume means it’s not as useful as it could be. A setting to adjust the deactivation time would be useful too.
Networking is via 10 / 100 MBPS ethernet or dual-band Wifi with full support for Mesh networks. I’m surprised that even the WiiM streamer don’t include gigabit ethernet given their high-resolution file support, meaning that streaming via WiFi would be the preferred option in most cases if your router is remotely modern). You can selectively disable the 24gHz wifi band if your router supports 5gHz connections, and you can also disable wifi roaming if you have a mesh network with many devices. I didn’t experience any issues using an Asus mesh network with roaming left on. You can disable IPV6 support (not sure why you’d want to do this), bypass DHCP to configure your network manually, and (by default) prefer Google public DNS (126.96.36.199) over the DNS server used by your router. Public DNS servers are usually faster than the DNS servers provided by your ISP, and using them removes one avenue for your ISP to keep tabs on your internet activity. I always advise configuring one globally if your router allows you to, but it’s nice that the WiiM Pro Plus bypasses ISP DNS by default.
Finally power is via a USB type C connector. 5V at 1.5A is required. A 5V, 2A adapter is included, almost perfectly resembling Apple’s old iPhone power adapter.
I have not (yet) tested a stock WiiM power supply. I was informed after publishing that my sample was an early production model that idd not ship with a UK power plug, so the adapter pictured is not the same adapter that you will receive if you buy a WiiM Pro. I chose to use the robust and extremely well built Raspberry Pi power supply instead. You can use any USB C power supply you like, it won’t make any audible difference. There are already immoral companies making “audiophile” linear power supply ‘upgrades’ for these for those with more money than sense.
Setup is simplicity itself. I connected the line output to an analogue input on my Topping A90D preamp, and the coax digital output to my Topping D90LE DAC feeding the same preamp vi a balanced input. I then powered up the WiiM Pro Plus. Less than 30 seconds later it appeared in the WiiM Home app, and I followed the prompts to complete the setup. First allowing the app access to location services, Bluetooth and the network.
Then a few taps to give the device WiFi access, which was seamless and went without a hitch. Next was a choice of audio output – analogue, optical or coaxial. Note that only 1 can be used simultaneously.
You then give the streamer a name on the network. You can choose a name of your own or pick one of the many room names provided.
I skipped pairing of the included emote (more on that later). Likewise the automatic latency measurement. As I chose the coax digital output, I was asked to set the resolution. I can’t imagine any modern DAC would be incompatible with 24-bit, 192kHz PCM,
Lastly you’re encouraged to setup Chromecast, Alexa and Apple Home.
These are all self explanatory. I don’t have any other Amazon Echo devices in the house, but the WiiM devices have Alexa built in so you don’t need a companion device for Alexa voice control.
This was by far the quickest, most frustration-free setup process I have experienced in many years of playing with just about every streaming device on the market. Everything was seamless, and I was soon presented with the primary interface of the WiiM Home app. The app is split into 4 tabs – browse, device, search and settings, the latter giving you access to support and information and a mechanism to submit feedback.
The browse tab displays favourites and presets.
And a configurable list of streaming sources.
And physical sources (line in, optical in or Bluetooth). If you use the volume control of the WiiM device, or you have a WiiM amp, the latest update memorises the previous volume setting for individual sources.
You can disable sources you don’t use to clean up the interface.
Tapping a streaming source takes you to its browser. Here is the main page of BBC Radio. Stations are sorted by local stations, nations and regions or national broadcasts. Any station can be preset for easy access from the app or the remote.
TuneIn radio gives yo a bit more flexibility with filters for music, news and talk, sports, podcasts, local stations or audio books with further filters for each category. You can search the tuneIn database and login to your TuneIn radio account to synch favourites and access premium features with a subscription, but none of that is required.
If you prefer an alternative radio directory there is a very nice vTuner implementation.
And radio Paradise for the Audiophiles and jazz lovers.
And Calm Radio for when you want to kick back and relax with some classical or jazz. I don’t have subscriptions for Calm, Tidal, Qobuz or Amazon Music so I haven’t tested those integrations, but others have and I have no reason to believe they don’t work as advertised. Likewise I won’t cover Spotify Connect, as it uses the Spotify app as the only means of control and therefore if you are a Spotify user, you already know what the interface looks like. We can take a look at the DLNA support though. Here are the servers on my network:
And the browsing options (all music, playlist, smart playlist, by album, by artist, genre, artist / album and album artist):
And when Quadro – an ageing Sinology DS418 NAS – finally catches up, we can browse and play content:
And besides playing, you can insert tracks into the current queue, create playlists and add tracks, albums, folders or anything else to your favourites
You can browse on-device music too, though as previously mentioned there is no native Apple Music support. You have to use the Apple Music app and AirPlay for that, which is a shame as you can’t take full advantage of the 24-bit, 96kHz and 192kHz content in the Apple Music catalogue. AirPlay is limited to 16-bit, 44.1kHz streams, which are supposedly lossless. However AirPlay2 streams are not continuous, and content streamed via AirPlay from the Apple Music app is encoded to 256-bit AAC before being streamed to the AirPlay receiver, so it is far from lossless albeit still perfectly listenable. It’s an irritating limitation that is entirely Apple’s fault. AirPlay can theoretically support 24-bit 48kHz streaming, but only when content is streamed from a HomePod to an AirPlay device as part of a stereo pair or multi-room setup. The latest firmware fully supports Airplay Cast.
I’m a first-time Alexa user and had hoped it might bridge the Apple Music gap. I signed into the WiiM Pro using my Amazon account, and proceeded to the Alexa app to add a few skills. Sadly the Apple Music skill only supports Amazon devices and Sonos (more Apple insanity), but other skills work well including BBC Sounds, Spotify, and skills for smart device control. It can do everything your Alexa can, including speaking welsh (NSFW), telling jokes, answering trivia, providing juvenile (but funny) lavatorial entertainment, and performing mundane tasks like setting alarms and timers, reading the news or telling you what the weather is supposed to be doing, contrary to what’s happening outside your window. It’s also useful for controlling Apple Music, though my usage of that is limited as I don’t subscribe to Apple Music unlimited. I do use the ad-free podcasts included with prime though, and am an audible subscriber, both of which were enhanced by using Alexa.
Elsewhere in the app, the device screen lists your devices and their current status.
You can add devices from here and access player controls.
And ‘room settings’ which are the settings for a given device:
The Pro Plus includes the WiiM remote, optionally available for the Pro and Mini. The remote gives you physical controls for power / standby, source and four presets, along with volume, next/previous track and play / pause. The remote also includes a push to talk button and inbuilt microphone to communicate with Alexa. The remote gives immediate access to your Alexa skills and Amazon Music (for prime or premium subscribers) by simply holding and speaking. Alexa is responsive to commands and the implementation so intuitive that I’ve found myself reaching for the remote more than I do my phone.
There’s another advantage too. Alexa on the WiiM is strictly push to talk. It’s not always listening, so there are no privacy concerns. If you’re worried about your privacy, don’t say anything you wouldn’t want anyone else to hear while holding the push to talk button. Otherwise, say what you like.
I wish the remote had an IR receiver and transmitter, so it could learn commands from an amplifier remote and act as a universal controller. As it is entirely software-based, adding additional actions for sequential presses, holds and multi-button actions would allow for more than 44 different functions when you consider the possible combinations and even more with ergonomic compromises. That’s enough to control an entire hi-fi system, even the rarely used functions.
WiiM could take things further with a Bluetooth IR module that interfaces with the streamer and its app. You could then have the WiiM itself learn and control functions of your amplifier – switching to the correct input when the WiiM wakes up, for example, or giving you control over an analogue CD player, cassette deck or other analogue source via the app when you’re streaming it across the network. This is something none of the players in the streaming game have achieved yet, but WiiM might well be the ones to do it.
And if they really wanted to push the boat out, have IR commands from the WiiM integrate with Alexa routines to automate certain actions. This would enable the WiiM Pro Plus to trigger other smart devices without any additional interaction, controlling smart switches to power up your amplifiers or dimming the lights, shutting the blinds, reclining your listening chair and drawing the soundproof curtains before an album starts. You could achieve most of this with Home Assistant or HomeKit automation, but it would be great if the WiiM could do it. The possibilities are endless, and, if they get it right, exciting.
Let’s take a look at the settings, of which there are many. Device naming, device info and network status are obvious, albeit unusually comprehensive. The real surprises come in the form of a 10-band graphic EQ with turnovers of 31Hz, 63Hz, 125Hz, 250Hz, 500Hz, 1kHz, 2kHz, 4kHz, 8kHz and 16kHz.
There are pre-defined EQ presets too – flat, acoustic, bass booster, classical, dance, deep, electronic, gain, hip-hop, jazz, latin, loudness, lounge, movie, piano, pop, R&B, rock, small speakers, spoken word, treble booster, treble reducer and a vocal booster.
You can customise the EQ to your hearts content with ±12dB of adjustment for each frequency. And if that’s not enough, you can choose a fully customisable parametric EQ.
You can choose between the three audio outputs – optical, coaxial or line out. You can also pair bluetooth devices and transmit audio via Bluetooth, to a pair of headphones for example. And you can output to an AirPlay receiver if you so desire, so the WiiM devices can interoperate with virtually any smart speaker or active speaker regardless of brand or model. Select line out, which uses the internal DAC, and the Pro Plus gives you a choice of 6 filters – sharp, slow, short delay sharp, short delay slow and super slow roll-offs, and a low dispersion delay filter.
These filters tailor the sound to your preference – though it takes critical listening to determine the difference, and I wouldn’t be surprised if telling them apart in a blind test would be as much a matter of chance as anything.
Choose either the coaxial or optical digital output and you can set a sample rate switch latency of up to 3 seconds. This can help avoid some pops, clicks and other digital noise with some DACS that can’t respond quickly enough to the switching of the digital signal.
Elsewhere you can set the output level of the line outputs to 500mV, 800mV, 1V or 2V RMS to match the input sensitivity of your amplifier. 2V RMS is standard and should suit most systems, but many older amplifiers and many active speakers are more sensitive and behave best with a lower input level. You can fix the volume output to use the volume control of your amplifier, or enable the digital volume control of the WiiM which can be operated via the remote or the app.
If you use the WiiM volume control, feeding a power amplifier or active speakers directly perhaps, you can set a maximum volume limit. A left / right balance control function was also added in a recent update. Lastly any WiiM device can play in stereo, mono or play either the left or right channel audio only, and there’s a DSP effect to add a quick fade in and out to the beginning of each track to reduce the transitions between them, something I chose to disable.
Standby mode is configurable though does little to reduce power consumption. The WiiM streamers automatically update their firmware between 2AM and 5AM in your local timezone, as long as they are powered on, in standby and connected to the network. While I was in the process of writing this review, an option to manually check for updates was added to the WiiM Home app.
Power consumption for the Pro Plus is about 2.6W idle and can reach 4.5W playing a 1kHz sine wave at 96kHz resolution. The Pro draws 1.3W at idle and 1.7W in playback, so the majority of the extra consumption seems to be related to the AKM DAC. I’d like to see a function in the app to shut down the DAC completely if using the digital outputs, and perhaps to have the DAC and output stage shut down in standby mode to reduce energy consumption. At these low figures the cost to run is negligible, but in a world where we’re all (hopefully) conscious of our energy consumption any improvement is welcome.
Trying to describe the subjective performance of any hi-fi product is usually a waste of your time and mine. We all have different ears, rooms, systems and tastes. It’s easier where mechanical components like turntables are concerned because I can discuss the effect of quantifiable aspects such as rumble, isolation, inner-groove distortion, tracking, sibilance etc. Where valves are concerned we can talk about harmonics and distortion, which is pretty much the only thing they do well.
Where solid-state, digital streaming hardware is concerned, however, I’m always amazed that my fellow journalists are able to pull so many audio cliches from their audiophile thesauri. Pace, rhythm and timing, air, space, layers, noise, sound stage, and so on. Edgar villchur, found of Acoustic Research once said “if they held a pistol to my head and asked that I design a turntable with very good sound stage, I couldn’t do it, because I wouldn’t know how.”
The WiiM Pro Plus sounds as good as the streaming source and should, for all intents and purposes, outperform any of the capabilities of the streaming sources we have today. What it gives up to the best measuring DACs is a few parts per million in distortion figures, a few tenths of a dB in linearity, and a tiny bit of signal to noise. Is any of that audible? I’ll let you decide.
I ran the review sample of the WiiM Pro Plus into my Topping A90D as a preamp, which in turn feeds the Hypex Nilai 500 monoblock power amps. The components both exceed the noise, distortion and linearity measurements for the WiiM but I still couldn’t actually hear the noise the WiiM imparted, nor did I find it lacking in linearity.
Where it lost out to my Topping D90LE DAC, fed by the WiiM’s bit-perfect coaxial input, is in detail. The DAC gave me a little bit more detail in more complex tracks, enabling me to better distinguish musical nuances.
For example, being able to detect an almost imperceptible sharpness in the top E string of a finger-picked guitar on the right, while a rhythm acoustic plays chords on the left and a singer takes centre stage. The D90 also has a more gutsy output and is able to drive the preamp a bit harder, which contributes to a less congested performance. In reality this is not something most people would notice. My preamplifier is a more challenging load than most.
I could tell you that the WiiM Pro is “brilliant for the price” or some such nonsense, but that’s not entirely accurate. The hi-fi industry might hope to convince you that performance scales with price by default, but that couldn’t be further from the truth. It’s often the case that products from far-eastern manufacturers exceed the technical specification of anything in the high-end for a fraction of the price, and such is the case with the WiiM Pro Plus. What you’re actually getting is a very nice DAC with excellent technical performance, even judged by the standards of high-end solutions. You’re also getting a feature-packed streamer, one that supports more services in a single unit than most standalone streamers do, with great software to boot.
Throughout my time with the Wii Pro Plus review sample I didn’t experience a single dropout or lost connection. It just works, and has been doing so reliably since I plugged it in just prior to Christmas 2023 (it’s now February 2024). It has never failed to carry out a software update, the app has never failed to find it on the network, it has never failed to re-establish its connection even when the router went offline for a time. I can tell you from bitter experience that I have never in more than a decade of using standalone hi-fi streamers, had one be as reliable and fuss-free as the WiiM Pro Plus has been.
There are some absent features that I hope will be considered for future generations. A USB port or 2 for local storage, CD drives or ancillary devices would be nice. An IR blaster and software configuration interface for controlling the rest of the hi-fi via the Bluetooth remote or via the smart home. Gigabit ethernet, which should be standard these days. A better power supply – audiophile approval isn’t necessary, just a nicer switching power supply provided with the unit would be just the ticket.
New software features are being added all the time as the platform evolves. WiiM are actively developing their streamers and there is a large community of users over on the official WiiM forum who provide support, interesting discussion and contribute suggestions directly to the company. And WiiM are listening, as many of those suggestions have already been implemented. The roadmap is transparent too. Hi-fi manufacturers take note, this is how it should be done.
So no, I won’t tell you the WiiM Pro Plus is “good for the price”. I’ll tell you instead that in my opinion it is setting the standard by which all others should be judged, regardless of price. It’s the best combination of hardware and software I’ve seen in the hi-fi streaming sector to date, and represents the kind of value for money that is never given the recognition it deserves by the industry, especially the press. If you want to stream audio to a hi-fi, this is the little box you should buy.