Synthax Audio UK customer Robert Slowley recently visited Synthax HQ to try out the new RME ADI-2 Pro.
Having now spent some time with RME's latest high-end converter and headphone amp, he gives us his thoughts on the device in this in-depth review.
Review of RME's ADI-2 Pro
Robert Slowley
4 months ago I entered the the high end audio world with a pair of Audeze's LCD-3s (2016 Fazor version). Being new to the world of high end audio equipment I knew I needed an appropriate DAC/Amp to get the full experience of the LCD-3s, so I tried a variety of DAC/Amps (Objective2+ODAC, FiiO E10K Olympus, Late 2016 MacBook Pro).
All the other amps I tried were clearly lacking, they don't have enough power to properly the LCD-3s, so the volume was fairly quiet and notably distorted near maximum. I also found that they couldn't resolve the detail and micro detail (also called plankton) in my music as well as I'd been led to believe the LCD-3s were capable of. I began to trawl the internet trying to find out what 'audiophile' grade products would be an appropriate match.
A good friend of mine who is an expert in microchip design, digital signals processing, and an amateur musician to boot suggested I look at the RME ADI-2 Pro because in his opinion RME produce the best professional audio equipment available. Their technical excellence is second to none, and the ADI-2 Pro was personally overseen by RME head engineer Matthias Carstens with the goal of producing the best possible 'no compromise' headphone Amp / DAC.
For me there was no higher praise I could receive for a product, so I called Synthax to ask some questions about the ADI-2 Pro. After answering every question perfectly I was invited to come down and try it out in person in their office just off the M25.
The whole team, Jason (Sales), Rob (Products), and Martin (the boss) were absolutely fantastic, friendly, informative, easy going, and helpful. After a full run through of the feature set, how to use it, what the history and background of it's development was, etc.. I was set up with a cup of tea and the ADI-2 Pro in a meeting room and left on my own to try it out. I couldn't ask for a more friendly or helpful bunch to assist me in assessing the ADI-2 Pro and making a decision about purchasing it.
The industrial sleek design is absolutely top notch, excellently finished in every respect. You can really tell that it was a labour of love for head engineer Matthias Carstens. It looks beautiful, the spectral analyser on the high resolution colour IPS display is stunning, and the use of LED lighting complements the design perfectly.
Unlike the other headphone amps I'd tried there is absolutely no problem with power here, the "Extreme Power" mode will give you over 2 watts per channel! You could totally blow your head off with this if you wanted to (helpfully it has a feature to protect you against overpowering more sensitive headphones). It has plenty enough power for my Audeze LCD-3s, and I can be confident that my investment here will have the headroom to power my future headphones even if they are more difficult to drive than those I have now (as planar magnetic headphones often are).
RME are well known in the professional audio business for their outstanding technical excellence and dedication to measurably fantastic sound. The PDF manual is packed with SNR / THD graphs demonstrating their commitment to achieving the best possible sound quality that can be engineered. This stands in contrast to the often hand-wavy or vaguely defined approach of many 'audiophile' grade Amp/DAC products.
If you look in to the history of development of the ADI-2 Pro (see Youtube etc) you will find that in every engineering aspect RME went totally over the top in their pursuit of perfection (e.g. 768 kHz sample rate support), and it definitely comes through in the sound quality. It is a marvel of German engineering at it's finest. As a no compromise solid state DAC/Amp the sound character is extremely transparent, and is packed with absolutely tons of detail. When paired with high end headphones you will be able to hear detail and micro detail in your favourite tracks that you just haven't heard before. I guarantee it will absolutely blow your socks off as you appreciate your music anew.
"you will be able to hear detail and micro detail in your favourite tracks that you just haven't heard before.
I guarantee it will absolutely blow your socks off"
For me the audio quality of the ADI-2 Pro has been an absolute game changer to the extent that it's actually pretty dangerous. It is very easy to get totally lost in the music, if you have your eyes closed you can lose all sense of the world around you and really believe you are there in the performance.
When I first got it I often found myself listening for 8 hours straight to music in bed with it (something I never did before), or falling asleep through exhaustion with it still playing away because it is just so good that when you start you won't want to stop listening. As a married employed man with children this is quite hazardous, so now I have to be quite careful when using it!
It is (for me at least) an expensive purchase, but it is one of those purchases I don't regret, it really is more like an investment. So well designed and with so much capability and headroom that it's going to last, and RME are regularly updating the features and improving it with regular firmware updates.
Are there any downsides? To be honest if it fits your budget it's a struggle to find any. It can get quite hot in operation (but continues to work flawlessly), the menu controls are not intuitive (but fine once you've learned them), and although it has a 'dark mode' which dims the IPS LCD panel and puts it in black and white mode, the white LCD rings remain on at full power. If like me, as a guilty pleasure you like to listen in the dark with your eyes closed so you can be fully immersed, you will find you need to put something in front of the ADI-2 Pro to block the light, and RME have confirmed this can't be resolved through future firmware.
An unexpected omission is that it does not come with a USB cable, so you will need to separately buy a USB 2 type A to type B cable (often referred to as a 'printer cable'). As there is no established standard for headphone balanced cables you may find as I did that it does not support the balanced connector your headphone uses (4 pin XLR in my case). The manual includes a wiring diagram to show how you can make an adapter, but as far as I can tell there is no UK source for these adapters premade so you'll need to get the soldering iron out or ask someone to custom make one for you.
"The ADI-2 Pro is jam packed with every feature you could imagine,
and a few you probably haven't even considered"
If you're a tinkerer obsessed with audio you're going to fall head over heels in love. The ADI-2 Pro is jam packed with every feature you could imagine, and a few you probably haven't even considered (ever wondered how different D to A filters alter the impulse response? well you can switch between 4 different algorithms to find out!). There is a gold mine of features and ports (including 2 headphone jacks so you can compare headphones easily or share the audio love with your better half) that I haven't used (e.g. the DA converter, running it from a battery, etc..), and a plethora of software capabilities (5 band parametric equalisation, loudness, crossfeed, etc..) that I have yet to fully explore. The 88 page manual is filled to the brim with technical information, block diagrams, circuit diagrams, graphs, and figures – showing RME's devotion to technical excellence and design. Support from RME is outstanding, if you go to their online forum and ask a question you'll quickly get an answer from the engineer who designed it.
If you're someone who just wants the best possible headphone audio quality but doesn't want to spend an eternity reading manuals and configuring things you will find it's pretty much plug and play. On Windows and Mac you just plug it in via USB and it 'just works', start playing your music, plug in your headphones, turn the volume knob, and you will be in audio Nirvāṇa.
The ADI-2 Pro is a phenomenal no-compromises AD/DA headphone amp, a marvel of German engineering, it is absolutely worth the investment. If you love audio and want the best possible 'end game' headphone amp designed by the best engineers in the business then look no further. Be careful though, it's not just good, it's almost too good, your life will be permanently changed.
"If you love audio and want the best possible 'end game' headphone amp
designed by the best engineers in the business then look no further."
Our thanks to Robert Slowley. You can find out more about his work as a photographer by visiting his website here.
Find out more about the RME ADI-2 Pro
If you'd like to know more about RME's pro audio solutions, give us a call on 01727 821 870 to speak to one of our team or to arrange a demo. You can also contact us here.