Years ago, using Db Audio Lab’s earlier discoveries, their NOS Tranquility DAC fed by a carefully tuned Mac Mini, many of us heard that 44K/16 bit files could be much more musically complete than thought. Extracted eloquently and with minimal damage, Redbook could be very musical indeed.

Now, the Revolution Server modifications, with the correct models of Minis, have taken digital front end potential to levels I did not know were possible. Continuing Db Audio Lab’s commitment to refined digital-to-analog development, digital music that was great here feels like it has come to maturity.

Again...the great importance of source is made clear. If the source can’t show it, it does not exist! No matter how good the system, the dexterity in which a source extracts and conveys digital data defines the potential of the musical experience.

Even now, many DACs, transports, and servers sound impressive, but how many truly convey the sense of analog masters? In trying to solve digital in habitual ways, it is easy to lose or mask subtle and critical musical nuances needed to create the feeling of real music. Aside from challenges with servers and DACs, I am finding that virtually everything... power, cables, regeneration tools, filters, vibration…these and more can easily damage the fragile information from a digital file. Alternately, when extracted and conveyed optimally and completely,”digital” does not even come to mind. It can be beautiful music!



After so many years of digital development issues, I think it is hard to adjust our minds to the real possibilities of very high quality digital-to-analog conversion. Then, wading through myriad opinions, and hopefully able to discern what is relevant, we may get close…or maybe not! This is why I love to find people who have dug deeply, and who’s perceptions and analysis I can agree with consistently. It keeps me off the merry-go-round.

Eric Hider, of Db Audio Labs is one for me. His creative interest and ever-expanding listening and technical abilities are always instructive for me. Like Steve at Decware, the need for great music in the home drove him to become a developer. Also a musician and engineer who is comfortable exploring “outside the box,” Eric had a good background for creating the Tranquility DAC and Mac Mini-based Revolution Server. His development was driven by exhaustive blind listening tests in multiple high quality systems, the references, analog masters. From deep focus on front end development, I think Eric has developed pretty impeccable discernment and listening analysis.

Years back, Eric’s Tranquility DAC was “a revolution” itself. This 44/16 Non-Over-Sampling DAC was created in a time when hi-resolution, async, digital lenses, up-sampling, and all kinds of other circuit heavy “refinements” were the trend. Trying to integrate hi-res, and complex jitter and noise solutions, blind testing indicated that benefits often came at a cost, masking subtler qualities from the vast complex of what makes natural music. So they continued to refine a simple NOS circuit, feeling it offered a more real musical experience. To many, the super simple Tranquility seemed crazy until they heard it. And even many years later, by comparison, updated Tranquilities excel at revealing fragile analog musical attributes, particularly spacial and other very fine detail information.

This seems to be a crux of getting digital to sound analog. If the very fine information is preserved and conveyed with resolution and integrity, all aspects of the music benefit.



In retrospect, I think the Tranquility DAC’s ability to convey analog nuance musically was a big player in why my system grew as revealing as it did over time. And as improvements revealed more, the Tranquility’s dexterity as a DAC revealed more. It changed the baseline of perceived possibilities, while showing just how critical subtle information is… with it intact, the more obvious aspects of signal were more complete and beautiful. Like with Decware, the more revealed by system/room refinements, the more became available, potential seeming limitless.

So for years, without buying major pieces, I refined what I had. My Mac Mini/Tranquility DAC reference proved so satisfying, many popular and relatively affordable DACs came and went... Auralic Vega, Schitt Yggdrasil, Chords, etc…..and who knows how many transports and servers.

Then, about 14 months back, with reports of hi-res/DSD DAC advancements, and of player software creating very musical computer upsampling of 44/16 files, I started modifying the very inexpensive (for what it is) Gustard x20pro DAC. Served by my tuned Mini, one mod at a time, the DAC woke up. Running all Redbook files, resampled to 352.8 PCM or DSD 256 with Audirvana Player software, it was so fun to explore refinements through modification, I stayed with it.

Having had the Tranquility DAC as reference, I knew the modified Gustard was good at conveying the more fragile aspects of the music, the finest detail and space. Also, I think the Tranquility had helped me learn the subtler language of more elusive analog qualities, making awakening these qualities with modification choices easier. Whether the tuned up Gustard is better than the latest Tranquility is another test, but it is very good! With recent versions of Audirvana really stepping up, the Mini/Gustard became my reference source as I worked on progressive amp modifications and cable development.



Fast forward to about six months ago. While looking at digital converter sound https://www.decware.com/cgi-bin/yabb22/YaBB.pl?num=1510063488 the thread segued into some popular new servers. My amps and DAC mods had reached amazing levels of musicality, and relaxing a bit from the immersion of that exploration, I got the server bug!

I can get overwhelmed trying to seek reality through the lens of so many forum threads and reviews, and have never been to an audio show. So knowing Eric’s level of knowledge on digital front ends (and everything else audio), I figured I should get his view on the relatively affordable state of the art.

Even after years of listening to his Revolution Server, and always careful not to be pushy, I could hear in Eric’s voice a sense of awe at how good the Revolution sounded. Digging more, it seemed others felt the same. Having released the Revolution mostly to his customer base, feeding the Tranquility DAC, a “feedback loop” with known references developed. Asked how users responded, Eric said he is unaware of any finding server setups that beat the musical finesse of their Mini-based Revolution Servers. Considering advancements in high-end servers, and that many of these clients world-wide are cost-no-object audiophiles, that got my attention!

Also, the few years they showed at Rocky Mountain Audio Festival, Eric’s dB Audio Labs, with Pi Audio, Dodd Audio amps, and GR Research speakers...the room won:

- Best Sound for the money, 2012, 2013, 2014
- Best Digital for the money 2012, 2013
- Best Digital against all including cost no object 2014

The Revolution Server, feeding the latest NOS Tranquility DAC, won Best Digital three years in a row, including best Cost-No-Object Digital in 2014...And Best Room Sound for the Money all three years they attended!



The Revolution

In previous Mini work, limiting Operating System processes along with effective hardware modifications were highly beneficial. Then, in developing the Mini-based Revolution Server, they discovered that deeper OS process cutting could produce logarithmic benefits. Finally more than 200,000 lines of OS code were removed! Narrowing down to the best Mac Mini models for music, and continuing refinement of hardware mods, the Revolution Server was born.

Though difficult to quantify with our limited knowledge of digital, it did not take long for folks to hear that this OS, in an already great server platform, was a game changer. Still a Mac OS, the musical qualities from the adjusted OS were shockingly analog. Amazingly, they found the OS itself was as powerful for natural musical creation as all the other Mini optimizations together. These included the best sounding: battery power, fast memory, SD drive, external drives, vibration reduction, USB regeneration and noise reduction, dedicated USB cables….How could an OS do so much to solve long befuddling digital-to-analog bottlenecks? Though the earlier Mini refinements were really important, this OS’s purer, truer, realer “analog” presentation brought the rest to fruition.

Analyzing and enjoying the Revolution for 12 weeks or so, I agree. It offers amazing beauty, the more refined front end making the rest of my system/room much better! The same music files I know so well, using the same Mini, the same setup and settings… By adding the Revolution OS, every single musical attribute is notably improved, almost to a point of impeccability in my system. The data from the Revolution clearly retains enough integrity to advance the music to notably more complete levels! And this is all in the digital domain, before the DAC cable!



For me this brings to question our real knowledge of digital music creation. These files were “bit perfect” before the Revolution upgrade, yet the OS delivers deep refinements in the musical experience. Not only are digital/electronic artifacts unheard or more deeply resolved, the revelation and resolution are sort of shocking…..seemingly endless...very smooth and complete; empty space and ambient space more clear and present; fine detail and harmonics more complex and complete; and speed, dynamics and density took me aback! In fact, at first I found the Revolution overstated in dynamics and signal density on many recordings. By the way it delivers data, it increased density and dynamics enough that my previous system balancing was too much!

A primary density/clarity tool for me is my modified CSP3 pre. First I turned down its input tube pots from 9 to 8, and the output pots to 7 rather than my usual 8, relaxing punch, clarity and density a bit. Also, madscientist black discuss pieces, and some signal resolving stickers I tested for him (similar in effect to WA stickers), in balance, these had been helpful in enhancing signal density and clarity. I particularly like them for power, but also in some signal areas. Pre-Revolution, I had really nice balance with quite a few of these in strategic places… circuit breakers, cable ends, connections, chokes, over/near power supplies… I started taking madscientist pieces off the computer setup...a black discuss stick I had cut in half and put across the power/fan areas of the computer; then little stickers on cable ends, over each port, over the power supply, I removed about half them.

Density and dynamics re-balanced, I more easily heard the many refinements from the Revolution Server...extraordinary really. It still amazes me that the OS itself had increased dynamic signal integrity so much I had to calm my previous balance of dynamics and clarified density.



As I learned the Revolution Server’s potential, the delicacy and completeness of the signal information became more and more obvious. After many years of computer audio, having upgraded Minis and player software, cables, power, USB, etc, all these were relevant, but this was another level!


Now the resolution is more reminiscent of tape, big and complete, and without excess signal concentration. And in balance with the system, enhanced dynamics, density and flow are powerful and musical enough that I can enjoy music at notably lower volumes, while not feeling unnaturally saturated...a delicate balance in my experience. Each day I continue to hear more beauty, more subtle improvements, and likely many things I have yet to discern.


Taken individually, each Revolution refinement could be heard as sort of subtle. But it so gracefully refines all analog qualities, the whole is far from subtle to me! Having worked so long to create the engaging musical experience, where subtle issues can weaken the feeling...it is difficult for me to even think… But in my setup, this server has gone a long way toward solving digital! Not in the face, its “signal” is so refined it awakens every aspect of what can make music feel and sound like musicians playing. Like the Tranquility DAC had earlier, the Revolution Server will no doubt teach me as its abilities unfold in perception.

More signal integrity, revelation and resolution, it is easier to hear everything in the sound field more deeply and completely. The “analog” resolution is pretty vast, but ingratiating, not unforgiving. Richer...freer...excellent speed, body, complexity and ambient layers, and analog ease, it is more true, more engaging.

The Revolution took a front end that was exceptional into surprisingly more mature territory.
No doubt, all the amp, DAC, and IC work I have been doing helps reveal this. But whenever I pull back from just enjoying the experience, intentionally analytical, I notice what the server has done for the music. Time after time I am amazed. The Revolution’s contribution to smooth resolution, density, and relatively flawless musicality continues to bring to mind tape, but with the speed, dynamics, clarity, transparent adjustability, and convenience of quality digital. It really seems like a new medium to me!

Having nice equipment, a decent room, and very carefully developed synergy, the addition of the Revolution in my setup seriously helped bring the digital-to-analog dream to a waking state! I really can’t believe I am saying that! Sound Revolutionary?


PS: dB Audio Lab's Revolution Server proves (to me) that the computer server is more important than I could imagine...the beginning of it all.

But to hear this fully, it is important that it all works together, front-end and beyond, right? Considering the innate complexity of an audio setup, even with all good parts, depending on configuration, the combined source can be anywhere from decent to truly great. The cool thing is that Eric offers Servers, cables and DACS, but also a vast store of experience based knowledge. He has worked on natural and complete sound for so long, and in such depth, that in my experience, his advice can be quite revealing, open new doors to hearing, and help with effective use of time and money.

I called Eric and had a very good conversation.  He certainly understands the mini and how to make it sound good.

My only issue, and its not that big an issue, is that I would have to roll back to an earlier version of Audirvana, as they don't support Mavericks (which Eric's OS is based off of) in the latest release.

As always, thanks for your insights Will.  

I did have one thought. I was going to see if Eric would consider installing the server on my second (and unused) SSD in my main system mini.  I could keep the best of both worlds by simply changing the boot drive.

I have 3.2.8 so I could easily install it on that drive.

With two drives I could A/B and them first then remove the other drive and see if there is an impact.

Eric believes an external firewire drive with a certain oxford chip set provides the best sound.  I am pretty sure mine has it.

I have been using an SD card to hold my library but increasingly, I have been streaming Tidal.  I'd say that accounts for 80-90% of my listening lately.

I am in such a good place right now, that I am hesitate to change something major.  The bypass caps have seasoned as have my input tubes and I am getting really really good sound.