Review: ESP MUSE Mn Cast (raspiaudio)

Just one among many, or the best ESP32 casting audio player?

The first info about the unboxing and why I only received the black Mn Cast (black & white ordered) instead of the announced white one, you can read here and here.  

Prologue

As you can read on the picture, this is the first review (worldwide) of the ESP Muse Mn Cast from raspiaudio. This is also my first review, here on the blog. With hard technical facts, peppered with my personal opinion, which has crystallized in decades of experience as a music and IT lover. And even if I am already grayed (old fart). By the way, some say I look like Santa Claus with my long white beard (laugh). Nevertheless, I am not one of the eternal yesterday. Because I try to be always at the pulse of time, especially regarding technology. And I listen what and why my children, or the young people of today, do things differently, use them differently, like them differently or what is important for them.

So I move with the times, which are currently strongly influenced by thoughts of saving energy. And there an ultra low voltage ESP32 chip is exactly the right thing. It's the next step in the evolution, after the Raspberry Pi, or as a very reasonable enhancement to it. Because as a server system the ESP32 is not suitable, but the Pi. An ESP32 player and therefore SqueezeESP32 does not need an RJ45 connection/support in my eyes. WiFi is perfectly sufficient as a pure receiver for audio files. A SqueezeESP32 (aka Squeezelite-ESP32) audio casting player is therefore IMHO the most ingenious power saver for today. The entertainment industry can take a leaf out of this book.

And since I can not, unlike my children, say that English is one of my mother tongues. Please forgive me the one or other funny phrase or words. By the way, I am not any different in speaking German, despite the fact that it is my mother tongue. (laugh)

By the way, please don't be surprised if I don't mention some things (specs) at all or tear them apart (maybe only at the end, a bit - laugh), because IMHO they are simply irrelevant for SqueezeESP32 (aka Squezzelite-ESP32).

Well, enough about the preface and since this is my first review, which is mainly about playing music. There is now something proper on the ears, or rather the eyes. (laugh)

The most important hard and soft facts

ESP Muse Mn Cast

• SoC: Espressif ESP32-WROVER-B
• Xtensa dual-core 32-bit LX6: 80-240 MHz + low power coprocessor
• 4 MB SPI Flash
• 8 MB PSRAM
• Bluetooth 4.2 LE (Low Energy)
• 2.4 GHz WiFi 4 - Draft N (IEEE 802.11n/150Mbit)
• Interfaces: GPIO, I2S, I2C, SPI, LED PWM, ...
• Crystal: 40 MHz
• Power: 3.3V - 500mA (advanced power-management)
• DAC: PCM5102A
• Line Level Output
• Pop free (Music & Power ON/Off)
• Software/Hardware Limited (SqueezeESP32/SoC): 16/32 bit - max sampling rate: 192k - max bit depth: 24 (spdif 20)
• Audio outputs: 
• Combined
• 3.5mm analog - stereo
  
• 3.5mm digital mini TOSLINK (SPDIF) - stereo
  
• Display: 1.3" OLED monochrome - 128x64 pixels - I2C / SH1106 driver
• Buttons:  Power ON/OFF, Standby, Rotary encoder with push button
• Power/Data connector: USB-C (2.0)
• Housing (3D print): black or white
• Dimensions: 
• width: 70mm (72mm with ON/OFF button)
• depth: 61mm
• height: 18mm (30mm with volume control)
• Total weight: 44g
  
• Available: EU, UK, USA only
  

Used firmware for this test: fw1.x - 16 & 32Bit (master-cmake : 1180)

 

Build quality case & board

The black case I have (rather dark gray) looks very good IMHO. Even if it is only 3D printed. It is matte and although it is plastic, feels very pleasant, slightly velvety and not cheap. Even though the whole audio player is very light with only 44g.

The case is held together on the back by 3 hexagon socket screws, for which you need a very small Allen key (bit). If necessary, you can also use a slotted screwdriver that fits exactly into the edges. Since the screws are made of metal, you have to be very careful when screwing them in. Otherwise the holes in the printed case will give way and the screws will not hold anymore. This is also normal with 3D printed cases. But why no normal Phillips screws were used is a mystery to me! This is open hardware, not keep it closed. Because not everyone has such small allen keys at home. But I do. (laugh)

The openings on the side for the combined 3.5mm audio output, USB-C, etc. are partly a bit larger than they should be. However, this is nothing unusual with 3D printed cases.

The PCB and the entire board looks very tidy and the solder joints also have a clean good quality.

 

 Audio quality

First of all, I didn't measure anything. Because as my father always said: If you measure a lot, you measure a whole awful lot. (which sounds in German much better, cause of the same word, used several times, but different meanings: Wer viel misst, misst viel misst). Therefore, I prefer to rely on my experience and, of course, my ears. And everyone has different demands, opinions and preferences when it comes to music reproduction. I listen to a lot of music via Spotify (only 320Kbs) with various Bluetooth headphones (AAC:320|aptX HD) when I'm on the road. Or at home via HEOS/LMS @ Denon AVR, with 7.2 speakers from Teufel. When I listen to music, but mostly in stereo 2.2 setup. If I want to have even better audio quality, I throw a vinyl on my TEAC turntable with external belt drive and let the Shibata needle (stylus) whiz through the grooves to enjoy even the finest nuances of the music (real HQ Hi-Fi Stereo). But that's not what this is about. Just so you have a picture of how my demands are.

 

The audio quality of the PCM5102A DAC is very good. No noise, no distortion and absolutely pop free. Both during music playback, as well as when switching the DAC on and off. None of my other ESP32 based boards/DAC that I have tested more intensively so far have managed that. Which surprised and pleased me very positively. Because I already bought, completely independent of the Mn Cast, two small I2S boards with almost exactly the same PCM5102 DAC. But these have only an analog and no SPDIF output. Since the volume is at line-out level, the overall volume when using headphones is logically somewhat limited. I only tested the analog output with my Bose Quite Comfort II headphones and their 3.5mm cable without all the Bose audio enhancement voodo. With that, the volume was understandably a bit quieter compared to my Samsung S9+ (the last Galaxy with 3.5mm jack) and the Bose headphones. As for the max.volume. Still loud enough. Such a limit is better for the eardrums anyway.

The digital output of the Mn Cast I then tested on my Denon AVR. First with the 16bit firmware and then again with the 32Bit firmware. This also all worked wonderfully according to the limits of SqueezeESP32 and the ESP32 WROVER SoC. The FLAC HQ test audio files used were on my local NAS for all tests (analog/digital and SPDIF). By the way, I belong to the type of people who don't hear a big difference between 16Bit/48Khz and 24Bit/96Khz. Although my music system and headphones should allow that. Therefore I do without the much larger files as far as my own digital local music collection is concerned. But for the test I got extra free HQ files from the internet. And attentive readers will now surely have noticed, that 24Bit/96KHz is not supported at all, by SqueezeESP32 via SPDIF. Yes and no, because such files can be played somehow. But always with sooner or later dropouts (SoC hardware limit) or a complete crash, followed by a reboot. But it was long enough for testing the audio quality. In the meantime, I also wonder what added value the 32-bit SqueezeESP32 firmware has? I don't see a big one. Because the most common HQ audio format is 24Bit/96KHz and that is not properly supported by the hardware (only as analog output). But IMHO that does not interest the large mass of music listeners who use Spotify and co, at all. For them, the 16-bit (16/48Khz above CD quality) firmware is perfectly sufficient. Thus, a fully functioning 32-bit firmware would only be interesting for a very small layer of HiFi purists. But for what? No one can tell me that someone has a high-end music system in every room. (Really? Also in the kitchen, bathroom, guest toilet, hallway, stairwell, basement, attic, balcony, garden, garage, hobby studio, elevator, etc.. ) Because only then it would make any sense. Because such a player like the ESP MUSE Mn Cast and co, serve mainly as a single or multi-room extension, on old music systems, or active speakers, to make them cost-effective smarter and more modern and that in every conceivable place where the WiFi signal can still be received. To top it all off, it also has a very very low power consumption!

 

WiFi, Bluetooth & Multiroom @ LMS

When it comes to wireless music streaming, WiFi is always the best option. The Mn Cast, or SqueezeESP32 (aka Squeezelite-ESP32) supports both BT and WiFi. Bluetooth but only with the worst SBC codec. And anyway, with Bluetooth audio, the audio signal must first be converted with a codec, so that it can be transmitted reliably via radio. With the common licensed BT codes AAC:320 & aptX HD, this also works in a good quality. But, they are not supported by the firmware. Since the whole BT implementation comes directly from the ESP32 chip manufacturer Expressif. And it uses the free SBC codec which doesn't cost any extra license fees. We will will most likely see the change with Bluetooth 6, because that will be (according to the rumors) the biggest change there. A free codec for high audio playback via Bluetooth 6 capable device. Provided that transmitter & receiver both support BT 6.

When using WiFi, where much higher data rates are possible as with BT, you do not have to convert anything. You can send the digital file as it is to the DAC. Which is only an advantage, because every conversion of a digital signal, always further lowers the quality of the music and also further distorts. Therefore, Bluetooth is quite nice if you want to set up a standalone solution with the Mn Cast, completely without LMS server and active speakers (or even passive ones, when using a board with build in amp) or a sound system spontaneously, for example, on vacation, at a party, or at friends home.   

Therefore, the best way to listen to ESP MUSE Mn Cast (or any other ESP32-based player) music is WiFi. By the way, this is also possible on the road, e.g. with a mobile 4G router with built-in WiFi access point, or the WiFi Hot-Spot function of your mobile. The WiFi speed of WiFi 4 - Draft N (max. 150 Mbit) is actually somehow a bit "overdimensioned" for this. But more is always better. (laugh) For example, Spotify in the highest quality requires only 0.32Mbit. Therefore, I have not tested the WiFi function that much. By the way, I have never seen a slower connection like 54Mbit at my home. But at my home, the WiFi signal is almost everywhere good enough to receive all over the places in the house, as well as outside, a good signal. Thanks to 2 additional Mesh Accespoints I use. I have only two dead zones. But they are so small and directly behind rebar pillars that they are negligible and unsuitable for testing, because you really do not receive a usable WiFi signal there. In theory, 5Mbit according to the ancient WiFi standard A (1997) should be enough to reliably play music with the Mn Cast (or any other ESP32 player). With the 16Bit firmware and Spotify in the highest quality of 320kbs, the FW can buffer about 5-6 seconds. Which should also serve for somewhat longer WiFi disconnections, below the 5-6 seconds, so that there are still no music interruptions. Maximum is according to SqueezeESP32 (aka Squeezelite-ESP32) Wiki, with the 16Bit firmware, up to 10 seconds. The buffer can also be used for crossfade between the songs. So that the songs change / are mixed into each other without interruption as with good DJs. During my entire test, I could not detect any longer disconnections of the WiFi signal and thus interruptions during music playback.

During my Multiroom test with the Mn Cast, which ran as expected without problems, I noticed that the audio quality of the Mn Cast was audibly better than, directly over my Denon with the built-in HEOS. But that's probably because I can use the Denon AVR only halfway reliable via the Airplay protocol in connection with LMS and Multiroom. Airplay per seh already has its own limits (max. 16Bit/44.1Khz), which the Mn Cast so does not have (16Bit/192KHz or 24Bit/96KHz). The alternative DNLA plugin from LMS that comes into question, does not work properly with my Denon. The Denon is found and configured in the LMS DNLA plugin, but no music is played. Possibly just a problem with the configuration or the plugin?  But I don't care, because I just tested the solution to the problem. The ESP MUSE Mn Cast, is namely my solution. Because not only that the Denon takes much longer until he plays music from standby. Which makes the correct configuration for Multiroom much more difficult, because you have to include all the delays. So that the Denon can participate reliably in the Multiroom setup at all. In addition, it happens every now and then that the Denon over Airplay plays nothing and I must then first pause and then press play again.  The Mn Cast is immediately from standby there and plays the music reliably. Therefore, I have now decided that one of the Mn Cast comes to my Denon only for Multiroom. The switching of the right audio output on the Denon then takes over my Smarthome server on ioBroker basis. Because with that I can, thanks to the LMS plugin, reliably monitor when the Mn Cast plays music and then automatically switch to the correct output of the Denon. And all the delays of the Denon when switching on, are then completely irrelevant. Because the Mn Cast is already syncron with all other ESP32 players. It would be nice if everything would work directly with the Denon. But I do not have this hope at first, or rather long ago given up. Since all the major audio manufacturers, with their own multi-room solution (including Denon), only properly support their own completely overpriced closed multi-room solution.

 

Display, buttons, power supply & energy consumption

The monochrome 1.3" OLED display built into the Mn Cast, with a resolution of 128x64 pixels, is a very good choice. I already knew it from the Makerfabs ESP32 audio player and the Makerfabs MAKT32 board I own also. Which is why I bought the display also separately for my various DIY projects. It can be dimmed and also switched off completely. Depending on the operating mode, adjustable in LMS. Thus, a brightly lit Display also does not interfere when it gets darker and the player is in standby, and consumes virtually no power.

The aluminum volume control with push function works well and also seems high quality. You must not turn it too fast, because the software does not quite keep up with it! ANd when I say fast, I mean really fast.

The small button between the 3.5mm audio output and the power connector is too far inside to operate it with bare fingers. Also the position between the mostly with cables occupied neighboring inputs, make it rather unusable. It also seems to have only one fixed function, standby ON/OFF? That's all it does, at least for me. So more less useless.

The power supply is established via a USB-C cable. A cable or power adapter are not included, which I like. Becasue I own a whole box of micro USB cables and USB-A power adapters, from old devices. By the way, all the other ESP32 developer boards/dev kits I have. all of them have the outdated micro USB connector. This is where the Mn Cast also clearly stands out in a positive way. Since you no longer have to worry about plugging the cable in the wrong way and possibly breaking something. This has certainly happened to everyone. To me in any case. "Why doesn't the stupid cable go in ... Berserker USB cable mode on ... Ouch!. (laugh)
The USB-C 2.0 port also serves for data to flash the firmware.

The power consumption of the Mn Cast and also all other ESP32 boards/kits are in the absolutely mega hit suspicious range of 0.5 - 0.7 watts. I will not go into more detail here and now. Because there will be a separate article here on SqueezeESP32 - Info on that.

Quality defects and inconsistencies

With so much positive, there must unfortunately also be something negative. It would be too good to be true if everything was perfect. Unfortunately, I had to find out during my test that my display is defective. Already at the beginning I noticed that something is different with the display, as I know it from the other players.

After I turned the view of the display by 180°, it was very obvious to see. There are quite a few pixels already on the graveyard and celebrate their own party now. Hopefully with good music. (laugh)

Then I noticed that the volume control is not quite centered on the pin, because it slightly wobbles when you turn it. The cap is probably glued to the base unit, because you can't pull it off. Also not as nice as the aluminum shine would suggest.

Then I noticed that the LED2 that is used for the SPDIF output still lights up slightly even when the player is turned off with the main switch. Really strange. The power consumption is then 0.031 watts. But since the player doesn't have a built-in battery anyway, it can't be slowly drained even though everything is actually set to off. A USB power supply also switches off at such a low power load, or doesn't switch on at all. The same is applicable for an external powerbank. In each case tested with several different ones. Therefore, it can not be reproduced with a power supply or power bank. But by connecting the player to a computer to e.g. flash the firmare, because there is always power, no matter how big the electrical load is. Because exactly when flashing the firmware I noticed the problem.



Then there is the half-eaten PIN connector for the display. It works without problems. But quality conscious people and a proper QA would have to notice something like that immediately and not release it for sale. Best to alert the exterminator in the Fabrikc that they have small plastic-eating monsters in the halls.



As soon as my second white player arrives, I will check it for the same issues and report back here. Hopefully there is not a general quality problem with the Mn Cast. Would really be too bad.

By the way, the white one was shipped yesterday and should arrive on Thursday. Must now only check what I do because of the defective display of the black. Because that's what bothers me the most out of all the little problems here.

Things that the SqueezeESP32 world no longer needs, or for which it is not yet ready.

Finally, a few words about the hardware specs that I haven't mentioned yet. The board has very good possibilities to use it for other things, like an old school MP3 Player.  The Mn Cast looks under the hood somehow, like a slimmed down developer kit. Because a connector for a microphone and a SD card slot make no sense for the use with the SqueezeESP32 firmware. Even Apple has recognized the signs of the times and buried its iPod. And here are still SD slots built-in so that you have a fancy MP3 player solution? Seriously!

The opinions about the IR port are certainly divided. For my part, I don't need a medieval infrared remote control in my hands anymore. The future belongs to wireless technology, which is already well represented in the ESP32 with WiFi and Bluetooth. With this you can control the player much more reliably. Even without any visual contact. So what's up with the completely outdated IR? Let it go into its well-deserved old age. It has served mankind for decades, often well, sometimes very badly. But it has fully and completely fulfilled its purpose. So let him finally have a good retirement. Cheers!

And then the RGB LED, which is currently not supported by the SqueezeESP32 firmware, is already the future. Because it replaces all the single LEDs by being able to shine in all possible colors and thus display all possible congestion messages in one place. TOP, but currently useless, not supported by the firmware.

Conclusion

Is the ESP MUSE Mn Cast now the BEST SqueezeESP32 player?

Yes, definitely, because it is currently the only real player for SqueezeESP32 and on top of that it has a very good audio quality, without any pops!

OK, apart, in parts, from the SqueezeAMP player. But that's another story, not told here and now. The Mn Cast is despite the small shortcomings of my black copy, a full-fledged and good casting player that I can recommend to everyone. However, it is not the angel I was waiting for. But it is already very close. Closer than all the others. Because all my other boards are not finished players, but all just developer boards/kits with sometimes way too much unnecessary stuff that drives up the cost. And they lack a case anyway. But that's not what the Baords are built for. So no product that costs only what it should cost. And certainly nothing for the great mass of normal music lovers who do not even know how ingenious SqueezeESP32 + LMS actually is.
And everyone who says now: that's nonsense, I have a Raspberry Pi. It can do just as much, if not even more. Well, you have not understood. Because I have them too, but I will replace them all with ESP32 boards. The Pi will be given away together with the ESP32 I own too much. So that the presentees then also have a thrifty server for LMS. Because only with LMS SqueezeESP32 is really fun. BTW Because a Pi uses much more power than an ESP32 SoC and costs many times what they are actually worth. When will the chip crisis actually end?  Or does it go on and on like this?


//EDIT - UPDATE
Here you can find part#2 of the review, where I took a closer look at the white version of the ESP Muse Mn Cast.

Epilog: My wish for the future

The one perfect angel (ESP32 player). For me, there are two variants that would certainly inspire and fully convince the great mass of mankind.

Angel#1: In the form of an ESP Muse Mn Cast Mark II.
Without the completely unnecessary old pigtails, such as SD card reader, IR port, Mic connector and more or less unusefull standby button. The ESP32 SoC automatically goes into standby when no music is played. Seriously, nobody needs that kind of Futures. The rest can stay as it is. But it could be a bit smaller and a bit cheaper, because less useless hardware must be solderd to the pcb.

Angel#2: in the form of an ESP Muse Mn Cast Lite.
Same as Mark II above, In addition, however, without display and without the large volume control. Only two or three small buttons, ore like the 3 button jogdial the Makerfabs ESP32 Audio Player uses. So even smaller and cheaper than the Mark II.

Dream mode off!

Finally, something for the ears, including French flair. Becasue this is all about music.