October 2011

CEntrance DACmini Digital-To-Analog Converter And Headphone Amplifier
Forget about the component and, instead, concentrate on the music.
Review By Tom Lyle

  On their website, CEntrance proclaims that because they have more than a decade of experience designing equipment for other brands. The DACmini is not only differentiated by its circuitry, but their experience gives them a leg up over other DACs in regards to features. But to be honest, when I first heard about this component with the word "mini" in its name and its petite case in the photo on their website, I wasn't expecting much. But as the saying goes, "don't judge a book by its cover". Or, it seems, its title. The only thing "mini" about the DACmini is its casework, which was made intentionally small to both stylistically match Apple's Mac Mini computer and also to fit comfortably one's desktop with other computer audio gear.

I implore anyone who is even slightly interested in this DAC to visit CEntrance's website and take a look at the plethora of information they provide in regards to this component. I will briefly go over the highlights of its design and features, but there is hardly the space to delve into the detail in the manner they have. Added to this is a white paper that lists the "top ten" design features of the DACmini, and it goes into much detail regarding each feature. The list, without their elucidations:

1. Audio signal path with full galvanic isolation.
2. Digital signal path with JitterGuard technology.
3. Split-ground design, transformer-isolated power supply
4. Tongue-and-groove RF blocking aluminum enclosure.
5. Shielded cavity for source selection circuitry.
6. Smart source selection and power switch.
7. Heavyweight, grounded aluminum volume knob.
8. Drop-protection pot guard rail and EMC barrier.
9. Class A headphone amplifier.
10. Internal anti-vibration chassis stabilizer and EMC barrier.

Even though CEntrance may use their own methods or terms, these ten features should be pretty much standard in any product that markets itself as a high-end audio product. Still, to have all of them in a DAC that costs less than eight-hundred dollars is very nice, to be sure. One would expect the circuits to be properly isolated, a component should have a more than a decent power supply, and every switch and volume control should be high-quality. Its cabinet and innards should be free of outside electrical and radio interference, as well as free from excessive influence from outside vibration. And perhaps most importantly, these days any DAC worth its salt that is sold in the second decade of the 21^st Century should be designed to deal with jitter -- either lowering it to inappreciable levels, or better yet eliminating it altogether. But the DACmini has some boastful internal features, especially for a unit that most audiophiles would consider budget priced. The resolution when using the USB input can be as high as 24-bits with a sample rate of 96 kHz, and through its S/PDIF (coax) input it can decode signals with a word length of 24-bit, with a sample rate as high as 192 kHz.

Not only is the website loaded with informative text and diagrams, the DACmini’s downloadable pdf manual is well written and designed. CEntrance even makes available a custom universal ASIO driver that will aid one in attaining bit perfect performance from a computer's USB output. The DACmini is a driverless unit, that is, there are no discs one needs to install to operate when a computer's USB ports. Even so, the manual includes a number of pages dedicated to ensure one has the correct set-up with either a Mac or Windows computer to optimize the audio settings that one would need to get music from the computer to the DACmini's USB input.

Hold It Against Me
I hope no one holds it against me that I did not use the CEntrance DACmini with any Mac gear. Nor did I use it in a typical "desktop computer system". True to this publication’s audiophile spirit I used it in two different high-end audio systems, one fed from not only from a USB cable attached to a PC music server with FLAC files stored on its hard-drives, but directly from a 75-Ohm coax cable from a disc player’s digital output connected to the DACmini’s  S/PDIF input. The other system, where it spent a great deal of its time used a Logitech Squeezebox Touch as a source, drawing from the wireless network the same FLAC files on these same hard-drives. Although I did test the DACmini's headphone amplifier, I spent the majority of listening time using it as a DAC. Truth be told, I'm not much of a headphone listener when I am at home, ninety percent of the time saving their use for on-the-go listening. But that's just me. Therefore, to be fair to the internal headphone amp of of the DACmini, I will just say that it was good, and blew away the internal headphone jack on the old FM receiver under my desk. But it wasn't as good as my dedicated Headroom headphone amp, but that might not be a fair comparison.

I appreciate that these days many desktop computer systems, not to mention the people who listen to them, are much more demanding of high quality sound than ever before. My testing "only" included dedicated two-channel high-end systems, yet my use of both USB from the computer and a Logitech Squeezebox fed to the DAC's coax and optical digital inputs should ensure that these desktop listeners are happy listeners when seated in front of just about any computer’s music system that includes a CEntrance DACmini.

It took less than five minutes to unpack the DACmini, set it up in the second system, and begin listening to music. That’s when I took back any preconceived notions I had about this unit – it is only "mini" in that it has a small cabinet. The DACmini is encased in nice thick brushed aluminum case, and seems to be manufactured with as much precision as any other high-end product in my arsenal, albeit with curved corners as to resemble the look of a Mac mini computer. The front panel layout of the DACmini is both comfortably ergonomic and at the same time gave me the feeling that CEntrance really cares about the quality of the controls used in this unit. On the far left of the front-panel is the 0.25-inch headphone jack. To the right of that in the center of the cabinet is a nice large, smooth running volume knob that controls the headphone volume or the analog outputs of the DACmini if a variable output option is installed. On the right is the selector switch, which operates by clicking the switch in either direction, illuminated a small blue LED above the selector. This selects between the USB, coax, optical, or analog (line) inputs. There is a comforting "click" made by the switch when choosing a particular input, but no clicks or any other extraneous sounds or any other anomalies were transferred to the system's speakers due to the operation of the DACmini during the entire review period.

The back panel of the DACmini has on its far left side the input for the external power supply above the USB input. The proximity of the two inputs was not at all inconvenient as the power supply jack was of the miniature variety, and the USB cable's input jack narrowed down small enough at this end of the cable to easily fit into the socket even when handled by my stubby fingers. Next to the USB input are from left to right, the coax, optical, left and right RCA analog inputs, and left and right RCA analog outputs.  The RCA outputs were spaced far enough apart for me to use a rather thick pair of Cardas interconnects without too much trouble. Also, even though the Cardas cables are somewhat unwieldy (at least compared to some others that have graced this system) since the DACmini weighs nearly 4 lbs, these interconnects did not lift the unit off the shelf. The DACmini gets power from a power supply that is not as some might assume via an AC receptacle hugging wall-wart. CEntrance instead uses a unit that I've heard at least one designer describe as a "tabletop" power supply, though in this case I guess we should call it a "desktop" power supply. And since it has a power cord receptacle one is free to attach a power cord of one's choosing to route the AC into this small box.

Even though included in this system are a couple of disc players where I did connect a digital output to the DACmini, but most of the time I connected a Logitech Squeezebox's coax output via an MIT 75-Ohm digital cable to the coax input of the DACmini. I accessed a host of files from my server two floors above this system via a wireless network. The large majority of the files were 16-bit/44.1kHz FLAC files, but I did have some higher resolution files I downloaded from HDtracks as well as some files hi-rez files that I created myself. The system was powered by tubes, with a pair of PrimaLuna monobloc power amps and a Balanced Audio Technologies (BAT) linestage. The stand mounted two-way speakers were by Dynaudio.

The DACmini also spent considerable time in the big rig upstairs. With more powerful solid-state amps by Krell and Edge powering rather large electrostatic hybrid speakers I was able to hone in on the CEntrance's sound a bit more. If one considers the second system listed above a cut above the average desktop computer system, this system was staggeringly better (not to mention that there were a couple of cables in this system that cost more than the DACmini). Here the DACmini was fed from the digital coax output of an Oppo BDP-83 Special Edition universal player spinning DVDs and CDs, but was more often than not was fed from the USB cable connected directly to a 3.20 GHz Dell Studio XPS PC with 8G RAM running Windows 7 with 4TB worth of external hard drives storing the FLAC files. I played these files on Foobar 2000 and MediaMonkey v3. But fear not CEntrance. The DACmini was not embarrassed one iota by being part of this system, and so my comments regarding the unit’s sound quality are in regards to its performance in both.

Zippo
After I let the CEntrance DACmini break by listening to it off-axis for quite a while, the first thing I noticed regarding the sound quality of the unit was its total background silence. I mean zippo, nada, zilch, nix, nyet, zero, no noise coming from this unit that didn’t originate from the source material. Whether this is due to Design Feature #5, the shielded cavity for source selection circuitry, or #10, the internal anti-vibration chassis stabilizer and EMC barrier, a combination of both, or just good design principles put into practice, I'll probably never know. It hardly matters. Most audiophiles are well aware that a  black background adds to not only the subjective impression that music sounds more like music (in other words, lifelike), but there is also no doubt that it increases the sound quality in a host of other areas, not just both the macro- and micro-dynamics, and the soundstage abilities of a product. Individual and groups of instruments floated between the speakers free of the borders of the speaker cabinets when appropriate, and occupied distinct areas within the soundstage. This soundstage was appropriately scaled, and this soundstage contained multiple layers that added to the impression that I was listening not only to the original engineer and recording's intent, but the musician's intent as well. I think it’s also very important to mention that I heard very little, if any, difference between inputs other than what was responsible at the source. Hi-rez through the USB input sounded better than CDs fed through the coax input, not because the USB input sounded better, but because hi-rez signals sounded better than standard CD. Period.

One of the first pieces of music I play through the DACmini was "The Robots", by Kraftwerk, the version on The Mix, a compilation released in 1991 which is a compilation of newly recorded versions of tunes from throughout their long career. For the last thirty-five years or so the only acoustic instruments on their albums have been the human voice, and even that’s usually run through a host of processors. So Kraftwerk’s banks of synthesizers aren’t going to tell one much about a component’s ability to reproduce real instruments recorded in a real space. Quite the contrary, but that's not the point. More often than not I use this album just to get a handle on a components ability to reach the outer frequencies in an objective manner. One of the first songs, "The Robots", begins with a bass synthesizer playing the important musical motif that is instantly recognizable by their fans. After the first verse, a second bass synth with a totally different character enters with a more percussive throb, pitched below that bass synth. Both bass lines were reproduced with excellent pitch specificity. The transient response of the DACmini was also admirable; the leading edges of both these electronic sub-melodies were reproduced quite clearly and weren't muddy sounding, or what may be even worse in this case, cut-off before they reached their lowest frequencies. The subwoofer in the main system goes down well below 20 cycles per second, and even though these notes were nowhere near those inaudible sub-basement pitches the harmonic information contained within these bass synths and the synthetic kick drum were able to shake the room and my gut.  The DACmini was also able to sort out the track’s thundering low-end without getting confused by the juxtaposition of the two bass synths underneath the rest of the digital hubbub; I was able to follow both bass lines throughout the entire song. After the Kraftwerk, turning to actual instruments recorded in a real space rather than their synthetic instruments recorded in a synthetic space was not only very informative, but also quite enjoyable, thank you very much.

Of course when decoding higher resolution files such as those that I've been downloading from HDtracks.com during the last year or so, the DACmini sounded better than when decoding "standard" CDs ripped to the hard drive. But the characteristics that made the DACmini worth listening to didn't change, and all its positive traits were still present when decoding these 16-bit/44.1kHz files. I mostly listen to digital with this resolution because a huge majority of my digital is in this format. Still, as much as I love listening to the 24-bit/96kHz file of John Coltrane's A Love Supreme, my enjoyment of this album had much more to do with the material than the sound quality. Yes, I know one would like to know how the DACmini handled this album compared to how I've heard it played through other DACs, but rest assured, the DACmini was able to please the audiophile as well as the music-lover in me. As I've heard with other DACs in my system, the DACmini was able to give Elvin Jones' cymbals the realistically natural sizzle to which I've become accustomed. More importantly, I've become accustomed to Coltrane's tenor being rendered as quite palpable in this digital version, and the DACmini didn't disappoint. Of course, this music recorded on this album transcends the method in which it is packaged, and hardly needs a good system to appreciate. But when the system is good, or hopefully better than good, there is more to enjoy. The DACmini made this possible.

As a good example of how well the DACmini could perform with "only" standard CD-type resolution was with one of my favorite Sibelius albums. I didn't warm up to Jean Sibelius' works as quickly as others back in the day, I guess because they were missing some of the Sturm und Drangof other composers that I gravitated towards in my youth. Not enough blaring horns and bass drum whacks I guess. But those feelings didn't last long after I heard his Fourth Symphony – the bi-tones, tri-tones, and not to mention what some have described as a tonal clash in the finale were enough to get me to listen. Over the years I've come to my senses and realized what was should have been obvious to all that listen any of his works -- that Sibelius can paint an aural picture as good as any composer, and better than most, and often by saying less. I can think of only a few other Sibelius conductors that I enjoy as much as Paavo Berglund, and his version of the Fourth (paired with his Sixth Symphony on Finlandia Records) with the Chamber Orchestra of Europe is one of my favorite versions of this, and remains to this day my favorite of his symphonies. I figure there are only between fifty and sixty members of this orchestra, and Maestro Berglund and the COE manage to unearth so many more details in this work compared to it being performed by a full-scale orchestra.

The bass response of the DACmini was again shown to good effect throughout the CD. At the beginning of the symphony, marked quasi adagio, the lowest strings and winds take the lead with what seems like a tempo-less, or at least a very slow, not to mention very bleak introduction to what my ears hear throughout the symphony as his most somber work. The bass response of the DACmini doesn't disappoint at all in letting one hear the full measure of the double basses combined with the other low pitched instruments creating what many have imagined as the barren northern landscape of his native Finland. It is strange that in an interview with Paavo Berglund in the CD's booklet that when asked of a possible meaning behind the work, that one shouldn't try to analyze it too much because "it is just music." That is at odds with many who feel that when Sibelius wrote this in 1914 he was likely might have been affected by his recent cancer surgery, perhaps the first world war, or even recently hearing other composers' more modern works (and I'm sure many audiophiles would grimace upon reading Berglund's comments after dropping a wad of cash on their most recent hardware or software purchases. Just music? Indeed!). Berglund probably meant that one should not jump to too many conclusions after hearing a piece of music, but still.

While the piece unfolds, the DACmini's retrieval of the background ambiance was impressive,  so one can easily hear the sonic contributions of the space in which this piece was recorded. The Watford Coliseum might not be an acoustically perfect room, but I for one thought that the sound of this hall as recorded on this album is only a positive sonic contribution. The fact that the recording was engineered by none other than Tony Faulkner more than likely had something to do with this, and those who recognize his name will have no doubt that this is true.  The second movement begins with only a slightly more agile tempo. Yet it has only a slightly brighter outlook, the dotted quarter notes on the strings adding to, and this is only a slight exaggeration, the creepiness that Sibelius portrays through this work. Even though it doesn't have the sharpest transient response, The DACmini has a very natural way with the reproduction of instruments, because it more than makes up for this by bringing the natural timbre of an instrument to the fore. The brass that enters in the second movement and remains present for the rest of the symphony had a warm natural blat, and also mixed nicely with the warm acoustic of the hall. All the instruments had enough definition to draw me into the piece. As things build toward the conclusion of the symphony, details such as the flute solo that occurs slightly to one side of the orchestra, is rather than being a laser etched image  in the soundstage, it creditably floats in space between the speakers. It is a natural rendition of a natural event, and that is more than one could hope for when using any piece of audio equipment.

In both the systems the CEntrance DACmini proved that it can be compared not only similarly priced DACs, but those priced much higher. The only other DAC that I had on hand at the time of this review was the Benchmark's DACPRE. This go-to DAC has become in the years since it was first offered a benchmark (sorry) for affordable USB digital-to-analog converters. The CEntrance DACmini sells for about half the price as the edition of the Benchmark that I own. But it is worth noting that at $795 for the DACmini, the law of diminishing returns has not fully set in yet. This bodes well not only for the DACmini, but for the potential customer of DACs in this price range. One considering the CEntrance DACmini might consider $795 a stretch for a computer's desktop audio system, and the Benchmark's $1600 not even worth considering. In both review systems the Benchmark bettered the DACmini in many areas, but two characteristics that stood out in favor of the Benchmark were its transient response and its extension and power in the lower frequencies. Was the Benchmark twice as good as the CEntrance DACmini because it costs twice as much? No. Should one not buy the CEntrance because of this? The answer to that as well, of course, is no.

Worth And Value
The CEntrance DACmini is a fine digital-to-analog converter that is well worth its asking price. It is actually quite an amazing little box – the fact that it was designed primarily for use in a desktop audio system, yet still held its own in two different dedicated two-channel systems is quite a feat. In both of these systems the DACmini not only didn't embarrass itself, it sounded good enough to forget about the component and instead concentrate on the music. It is not only very good-looking, well built, and can decode not only hi-rez signals, but offers a choice of inputs including USB – and for good measure includes a decent headphone jack. Definitely check this baby out before spending more on a DAC.

Specifications
Digital:
Resolution: 24-bit (also supports 16-bit) 
Sample rate: USB: up to 96kHz, S/PDIF: up to 192 kHz 
Interface: USB1.1 or 2.0, driverless 
Local clock: 10 ppm precision, unmeasurable jitter 
Compatibility: Any computer running Mac, PC, or Linux 

Analog:
Nominal output level: +6.0dBV (RCA outputs) 
Frequency response: 0Hz...40kHz; +0.0dB / -0.1dB (line or digital inputs) 
Signal to noise ratio (A-weighted): 144dB (line inputs); 113dB (digital inputs) 
THD+N: 0.00022% (line inputs); 0.001% (digital inputs)
Crosstalk: -128dB (line inputs); 118dB (digital inputs) 
Output impedance: 25 Ohms (line output); 10 Ohm (headphone output)
Output Power: 1.5W (total), drives 32 -600 Ohm headphones 
Maximum output level: +13.5dBV (32 Ohms load), +18.6dBV (300 Ohms load), +19.0dBV (600 Ohms load)

General Specifications:
Audio Output: Gold-plated RCA line-out, stereo 1/4" headphone out 
Headphone Amp: Direct Class-A, no caps in the signal path 
AC Power: Globally compatible, 90-240V AC power supply included 
DC Power: +9 to +19V DC (1A) for external adapters, car, boat, etc. 
Internal supplies: Ground-isolated, filtered ±15V, super-clean analog rails 
Dimensions: 6.5 x 6.5 x 1.6 (WxDxH in inches) 
Shipping weight: 3.75 lbs.
Price: $795

Company Information
CEntrance, Inc.
8817 Mango Ave 
Morton Grove, IL 60053

Voice: (847) 581-0500
Fax: (847) 581-0901
E-mail: info@centrance.com 
Website: www.centrance.com