Allo USBridge Signature network player and network bridge

Allo produces all kinds of ‘sound cards’
of better quality for the Raspberry Pi. The USBridge Signature differs from earlier
products in that it uses the Raspberry Pi 3+ Compute Module while still offering HAT
board extensions like the DigiOne Signature. The Raspberry Pi has become the standard for
small board computers – SMB’s for short. As a result up-to-date Linux versions are
available as are many programs for music playback. But when using the Raspberry Pi for audio,
it has limitations too. Since it was never intended for serious audio
applications, it generates lots of electronic noise that deteriorates the digital signal
and thus the analog signal after conversion to analog. For those that think that digital can’t
go wrong, watch ‘Connecting your DAC #2: how digital can go wrong’. Allo has tried every trick in the book in
previous products to overcome the limitations of the Pi. Like using another, more suited small board
computer and using an isolator board between the Pi and the audio board. With the USBridge Signature, on review here,
they made a clever move. It maintains the software flexibility and
robustness of the Pi while at the same time opening the possibility to design audio-optimised
interfacing hardware. They use the Raspberry Pi 3+ Compute Module
on an audio-optimised circuit board. The Compute Module is the heart of the Raspberry
Pi on a circuit board the size of about a DDR2 memory module. This module is also used in non-DIY products. Explaining where to use the USBride Signature
is slightly more complex than usual since the functionality depends on the software
you install. This being a hardware review, I have limited
myself to the use of Volumio 2 and RoPieee. Volumio is a full fledged software music player
that will play your own music files from hard disk or network share, is a DLNA and Airplay
renderer, plays internet radio stations and renders music from Qobus, Tidal and Spotify. RoPieee makes the USBridge Signature a certified
Roon Endpoint, with optimally also DLNA and Airplay rendering. To use it as Roon Endpoint you do need a computer
with Roon server installed. I have reviewed both Volumio and Roon, see
the notes below this video in YouTube for links. DLNA, Airplay and Roon need a computer for
the server software while programs like Volumio only need storage containing music, like a
USB drive or network share. Regardless of the software used, you do need
to connect the USBridge Signature to a DAC, a digital-to-analog converter or an amplifier
with a built-in DAC. The standard version of the USBridge Signature
has a special USB output to connect to the USB input on the DAC. This signal has been cleaned up to keep jitter
low. If your DAC has no USB input, you can add
the DigiOne Signature board to it that adds SPDIF outputs. The DAC has to be connected to an amplifier
that drives a set of speakers. On the other side the USBridge Signature needs
to be connected to your home network over a network cable. Unless you order the optional Wifi dongle,
then you can use your Wifi network to connect it. Over the network you access the internet,
when needed. Like for streaming services or internet radio. It also provides a connection to your computer
or NAS containing for instance the DLNA or Roon server and your music. Depending on the software used you use a smartphone,
tablet or computer for remote control. The USBridge Signature needs to be powered
by an external power supply, preferably one of audiophile quality. As always with Allo products you can order
just the circuit board to build it in a case of your liking or order a case from Allo. You can also order a completely built unit
with the music player of choice already installed on the MicroSD card. I review the completely built version here. You also need a power supply. That can be any power supply suited for the
Raspberry Pi 3 or 4 – meaning 5 volts, 3 amps – but if you go for audio quality, you better
use an audiophile class power supply. I used the new Allo Shanti power supply on
which I will post a review later. The USBridge Signature case is of simple design,
measures 125 x 154 x 55 mm and weights 550 grams. On the front left we see two USB A sockets,
intended for Wifi and Bluetooth dongles. Further to the right two LED’s to indicate
network activity and power, with right of that the slot that holds the microSD card
with OS and software. On the rear we see the power input in the
shape of a USB C connector, an HDMI connector for connecting a monitor or TV, a USB A connector
to connect the DAC and the network connector. In the standard configuration the USBridge
Signature has one circuit board with the piggy back Raspberry Pi 3+ Compute Module.To keep
it compatible with HAT boards – the expansion type boards for the normal Raspberry Pi – there
is an expansion slot, called GPIO connector. GPIO stands for general purpose input/output. It also has four mounting holes for a HAT
board. The interfacing with external devices is not
provided by the Compute Module, this is where Allo wanted to make a difference. They use a Texas Instruments 4 port USB 2
interface chip and used techniques to make all four ports isolated from each other. For instance by using low drop voltage regulators
all over the place – more than 30 according to Allo. One USB port is fully optimised for audio
– the so called Clean USB -, two USB ports can be found on the front for Wifi and Bluetooth
dongles and the fourth port goes to this chip which is an Asix USB 3 to Gigabit ethernet
interface. It can also handle USB 2 signals – like used
in this case – and then is limited by the USB 2 speed. According to Allo the data throughput is at
least 330 Mbit per second. And that is far more than is needed for any
2-channel audio signal. If your DAC doesn’t have a USB input, you
can add the DigiOne Signature HAT board to the USBridge. If you want to use the case, you need a different
back plate, with holes for the BNC and RCA connectors and the second power input. I reviewed the DigiOne Signature earlier,
mounted on a normal Raspberry Pi. See the link in the notes below this video
in YouTube. In short it is a high quality SPDIF interface
board for the Raspberry Pi that uses separate power lines for the computer part and the
SPDIF interfacing. This is where the Shanti power supply comes
in handy since it offers not only a 5 volt 3 amp output but also a separate 5 volt 1
amp output. The latter can be used to feed power to the
clean power input of the DigiOne Signature. To start using the USBridge Signature you
only have to connect the network cable, DAC and power supply. You then insert the microSD card holding the
OS and player of choice in the slot on the front. If you have to make your own software SD card,
see the instructions on the site of the software supplier. I would order a ready to use card with your
USBridge Signature. Allo doesn’t offer RoPieee pre-installed
cards but the instructions on the site are clear. You can also watch my review of RoPieee. If you want Airplay, DLNA and Spotify rendering
next to Roon Endpoint functionality, install RoPieeeXL. The USBridge Signature is a step up from the
original USBridge that, by the way, did use a Sparky SMB instead of a Raspberry Pi. Using the Allo Shanti power supply the Signature
does outperform the original USBridge. It’s a pity I don have the original SOtM
sMS-200 anymore so I couldn’t do a direct comparison. But they can’t be far off. The sound quality is clearly on the top end
of my setup 2 or even the low end of my setup1. The same goes for when the DigiOne Signature
SPDIF board is added. It offers a slightly more relaxed sound, more
speciousness than the same board on a normal Raspberry Pi 3+ To say it in simple words:
it’s a lot of sound quality for the buck. The Allo USBridge Signature is a complex product
to explain to you for it is enormously flexible. If you just want a network player and no fuzz,
order the ready to use USBridge Player in it’s aluminium case plus the SD card with
the operating system of choice and the Shanti power supply. US customers pay $ 398 ex sales tax, Europeans
pay € 497 including VAT. Want the DigiOne Signature added, add $ 220
ex sales tax or € 270 including VAT. If your DAC has both USB and SPDIF inputs,
try the USB only version first. There are, however, DAC’s that sound better
when connected over SPDIF. As I have said many times, it’s not the
chip or interface but the way they are implemented. Right from the start Allo tried to produce
a good sound quality digital player based on the Raspberry Pi and they kept improving
at a high pace. I also like the switch from acrylic cases
to aluminium. Allow me to once again point at the progression
in digital audio, offering more and more audio quality at lower prices. That doesn’t mean that anything cheap performs
just as well but if you select your products with care, there are clear steps to make. That’s it for this week. There will be another video next Friday, as
always at 5 PM central European time. If you don’t want to miss that, subscribe
to this channel or follow me on the social media so you’ll be notified when new videos
are out. If you liked this video, give it a thumbs
up. Many thanks to all that support this channel
financially, it keeps me independent and thus trustworthy. If you also feel like supporting my work,
the links are in the comments below this video on Youtube. I am Hans Beekhuyzen, thank you for watching
and see you in the next show or on And whatever you do, enjoy the music.

16 thoughts on “Allo USBridge Signature network player and network bridge”

  1. Great review, Hans! Question: I have a Schiit Yggdrasil DAC which has both S/PDIF and USB inputs and I'm currently using an Allo DigiOne Signature with the S/PDIF input. Do you think the upgrade to the USBridge Signature would give me a better result?

  2. I'm stuck with PLEX at the moment. It's not bad, but I can't control the plex server with a phone or tablet (i.e, use them as a remote control) and I can't choose what room to send the music to a la Roon . I'm guessing this Allo wouldn't help at all because it's a plex software issue. Ideally I'd like to have sonos/roon capability without sonos or roon. I have a bunch of computers, tablets, phones, multiple amps and speakers, and about 4TB of music on an external drive, but to get close to what I want (send music to whatever room I'm in and control it all with a phone or tablet remote) seems like it's going to cost quite a bit more money. I'm thinking about going back to KODI with YATSE and then just buying a cheap streamer for each stereo system, but sound quality will suffer.

    Not sure what the best approach is. This stuff isn't that complicated, but it gets a lot more complicated when trying to cobble something together that sounds decent and won't cost much more money. The Bluesound Node 2i is very tempting because it solves (in theory anyway) the Roon. Plex, and streamer problem, but that would mean $500/room. That is not even close to being affordable.

    Lately, I've been running the Plex app on my phone (which accesses the plex server) and just plugging it into the stereo system of whatever room I'm in – or just listening to the phone by BT or wired headset. It works, but it's awkward and obviously doesn't make the audiophile grade. If anyone has any suggestions, feel free to reply.

  3. Thanks for the review ?The SD card reader can be ordered with eMMC card functionality which should improve speed / reliability. Nice if you could test this some time. BR, Per

  4. thanks. i wonder if what os is the my best os of mood audio, dietpi allo + GUI volumio, max2play. which one ? volumio?

    my system : [1 communication company router +1 my router, jriver jplay femto, only DLNA through 1 cell phone(mconnect)] + [only 1 pc(windows10 64bit)] + [Allo USBridge Signature] + [curious evolved usb cable] + [ifi micro iusb 3.0] + [Audiocadabra Ultimus3™ Plus Solid-Silver Dual-Headed USB Cable (New 22 AWG Design)] +[ifi ipurifier usb 3] + [rme adi2 dac] + [ genelec 8040bpm speaker]

    please, what os is the best ? mood audio or volumio?

    I`m gonna make my visa card payment now because of ur youtube channel…….

  5. A little disappointed that very little was said about the sound quality. A vague comparison to your memory of the SoTM SMS-200? Surely a better comparison would be to the more recently reviewed Project S2 Ultra which is conceptually very similar (custom board with RPi 3+ compute module). The Project review had a fairly detailed comparison to the higher end SMS-200 Ultra which I believe is a permanent part of the system; surely this could have been used here as well, even if just to show how good (or not) the USBridge Sig is.

  6. Thanks for this video Hans. From a pure sound quality perspective, should someone have a DAC with both SPDIF and USB inputs and willing to enter the streamers world using internet streaming services only, would you suggest to go for USB Bridge signature or Digi One signature? Or is there a reason to go for the combined option?

Leave a Reply

Your email address will not be published. Required fields are marked *