 When a manufacturer wants you to review a digital output board for the Pi and almost triple the price they normally go for, you wonder if he really has something special or is just bold, for I will not compromise on integrity. Every few days people tell me that since digital signals are digital, there is no difference between digital sources. All kinds of arguments follow, sometimes well thought out, though wrong and sometimes simply ignorant. Point is that if I only change one digital source for another, I hear a clear difference on my three reference sets or if the difference is small, primary on my big set of one. And I hear these differences for decades now, as do a lot of my colleagues. If you don't hear any difference, you might buy better gear or watch my series on audio hygiene just to improve your stereo. Or just don't bother, that's your choice. I bring this up here since the subject of this review is a relatively expensive digital audio output board for the Raspberry Pi and the big question of course is does it sound better than the clearly lower priced competition? So buckle up for this one. LO sent me a board and a housing and as with almost all Pi housings, it came as a flat pack without instructions and made me long for IKEA instructions. But on the LO's side there is a clear instruction video that will help you out. After assembly you end up with an elegant looking housing that especially with the current non-spring loaded microSD slot makes it somewhat difficult to change the microSD card and the same goes for the network connection. But then again, that's mainly a reviewer's thing. Normal people will insert a microSD and network cable only once and leave it there. According to LO, there are 10 low dropout voltage regulators. These have the advantage of having no switching noise at the expense of some heat dissipation. Having 10 of them on a board means that they must have been rather careful to supply clean power to the different parts and, for instance, keeping the noise from the Pi out of the digital onboard. Added to that, they also claim to use DC-DC converters that do the same but have switching noise and lower dissipation. There furthermore is extensive filtering, galvanic isolation and then reclocking using the Wolfson WM8805 SPDIF receiver to output the digital signal. There is no optical digital output for LO considered that to be a waste of quality and they are right. I advise to use Tosslink only when I suspect that galvanic separation is needed. The Tosslink connector has low bandwidth and if no galvanic separation is needed RCA is a better choice and BNC the best. Since LO has provided galvanic separation it would be wasteful to provide Tosslink. But they do offer BNC. Remember the SOtM-SMS-200 Ultra review I did? No, the LO-DG1 is not that good but it has the same charm as the SMS-200, the basic model. It performs clearly better than any digital output board for the Pi I have tested up till now, regardless the power supply used. And I used the Digi-1 mounted on a Pi 3B with the normal cheap wall wart connected to the micro USB on the Pi. The highs are surprisingly clean, there is more tonality in the lows compared to the competition and the stereo image is also clearly bigger and more defined. The SMS-200 with S-Booster power supply offers more detail and sounds more relaxed but then we are talking about €750 of gear as where the complete Digi-1 setup, Raspberry Pi, Digi-1, MicroSD card, power supply and housing is under €200. Compared to the HiFiBerry Digi Plus Pro, the Digi-1 has clearly superior highs, better sibilance control, more openness and somewhat deeper and better defined stereo image. It better have, given the price difference you might say, but I used the HiFiBerry Digi Plus Pro the way I described in the video HiFiBerry Digi Plus Part 2. The link is in the show notes. That is about the standard Digi Plus transformer version but the modification I did on the Pro is the same. And I used the Audiophonics linear power supply that cost €89 making the total cost of the HiFiBerry Pro setup the same as the Allo with the cheap wall board. Then I came across an interesting phenomenon. At the end of the day I wanted to enjoy some music so I selected the USB input on the MiTech Brooklyn to listen over the SOtM SMS-200 Ultra that now is standard in my setup 1. I left the Pi with the Digi-1 board connected to the SPDIF input of the DAC and kept it under power but not selected. I started playing one of my favorite albums, Urk by the Knits, a Dutch band and immediately noticed something was seriously wrong. The album contains strong sibilance but playing it over the Ultra and the Brooklyn, that's no problem. But it was now. Since I always will change only one thing at a time in my reference setup, I knew it must be the Pi Digi-1 combo so I disconnected the SPDIF and took the wall board from the socket. Immediately the sound as I know it was back. It appeared that the switching mode power supply was the problem so I replaced it with the Audiophonics linear power supply and that solved the problem. It also generated the question. If the switching mode power supply has so much influence on the main setup, how would the Digi-1 sound with the Audiophonics power supply? Well, slightly cleaner on the high end and more relaxed and certainly worth the 89 euros the Audiophonics cost or, if you like, slightly less for the iFi iPower, that is a switching mode power supply done well. I now couldn't resist to try the sBooster power supply too. That again gave an improvement but only slightly, audible on my setup one but not on the other two setups. And given the alternatives nowadays, it is not wise to equip a 20k stereo with a Raspberry Pi and Digi-1. Although it's fair to say that three years ago I would have been very happy with the Digi-1 on a Pi and fed by the sBooster. In my setup two, costing around 3k, it is a very fine solution when used with the Audiophonics or iFi power supply. And clearly the better choice than the competition. Whether it's worth the money in my setup three, a 1k set, I find hard to say since I was stupid enough to start with my setup one and once you have heard the artifacts of a device, you will hear them everywhere. My guess is that it will be noticed by some but not by all. For a simple digital output board for a Pi, the price of 99 US dollars seems steep. Rather steep. But it's no simple digital output board. It is of very high quality compared to the competition. Sure, use a microRendu or an SMS 200 and you get an Audiophile power supply and you get even more openness, more detail, cleaner highs and so on. But the testers setup with the standard power supply running the Rope A image and Rune came at about 65% of the SMS 200 sound quality using an sBooster power supply. Using the Audiophonics linear power supply brought it to say 75% of the SMS 200 with sBooster. And please don't ask me what 75% means. I'm just trying to give you an impression that that judgment will vary depending on your auditory system and your stereo. Let me also put it in another way. If you have a stereo in the same realm or higher as my setup one, the best choice I have found until now is the SMS 200 Ultra at 1700 euros or more, including a proper power supply. Below that the standard SMS 200 would be my choice and then the Raspberry Pi with the LO DigiOne board and the Audiophonics power supply. Please do understand that I haven't reviewed all available products on the market and if there is a manufacturer that thinks its product is better, please contact me. This review started that way and I'm glad LO did contact me. The developments in the digital music reproduction go quickly now, so if you want to stay informed, subscribe to my channel or follow me on Twitter, Facebook or Google+. See the show notes for the links. If you have a question, post below this video but please don't ask me for buying advice. See my About Questions video to find out why. If you like this video, please consider supporting the channel through Patreon and see super exclusive videos too. Just one dollar a month will do. The link is in the show notes and don't forget to tell your friends on the web about this channel. I am Hans Beekhuyzen, thank you for watching and see you in the next show or on theHBproject.com. And whatever you do, enjoy the music.