I’ve gotten the general impression that French hi-fi gear sounds sweet, with a tuneful, relaxed, enjoyable character that doesn’t impose itself on the music. So when offered an opportunity to audition YBA’s Passion PRE550A DAC-preamplifier, I eagerly accepted. YBA is a French company founded in 1981 by Yves-Bernard André, whose initials it bears.
The Passion PRE550A ($8000 USD) is a modern line stage in having both analog and digital inputs. Since all but the most die-hard analog fans today have some sort of digital source -- a CD player, a dedicated server, or a transport -- it makes sense for a line stage to include DAC circuitry. This saves you the cost of a separate DAC, connecting cables, and a shelf on your equipment rack. The PRE550A is a line stage, not a full preamplifier; YBA will soon offer a separate, matching phono preamplifier, the PH150. The PRE550A’s several analog inputs make it flexible -- in addition to your digital sources, you can connect to it a phono preamp, a tuner (remember those?), or a tape deck.
Several things distinguish the PRE550A from other digital/analog preamps. First, you can turn off its digital section when you play an analog source. Second, it has a direct input for an Apple iPod (or, presumably, iPhone) that bypasses the Apple’s internal DAC and uses only the YBA’s DAC. In addition to an unusually wide assortment of digital inputs -- I2S (RJ45), AES/EBU (XLR), S/PDIF (TosLink, coaxial, BNC), and USB -- there’s a network input (RJ45) that accepts signals from a 10 or 100Mbps network. Built-in Apple AirPort Express support enables the PRE550A to work via a wireless AirPort Express network. There’s also an S/PDIF output jack, should you want to send a digital signal to another component. All that’s missing is a Bluetooth connection.
Not unique but unusual is the PRE550A’s three cylinder-shaped feet, which should make the PRE550A stable on the rack and couple it to the shelf surface almost as well as fancy cone footers, without scratching the rack’s finish. The two rear feet are rubber-tipped; the front foot is metal, to enable the grounding of vibrations. Another vibration-reduction measure is the use of a heavy bottom plate of 9mm-thick aluminum. The thick, sculpted aluminum front panel should further reduce vibration, and it looks cool.
As you can see from the photo, the PRE550A comes in stylish silver, with a display window shaped like a New England Patriots football (a flattened ellipsoid) that shows the volume level and the input selected, in large, yellow characters I found easy to read from about ten feet away. Actually, the photo doesn’t do justice to the PRE550A; it’s among the most elegant-looking components I’ve had in my rack, with an appearance comparable to that of such audio jewelry as is made by Jeff Rowland and Dan D’Agostino, if less flashy and more elegant.
The PRE550A measures 16.8”W x 4.6”H x 14.8”D and weighs a hefty 27.5 pounds. Two knobs flank the display: on the left, Source; and, on the right, Volume. The Source knob, which has click stops, selects among the digital and analog inputs. The freely rotating Volume knob begins with a setting of “-80,” and goes up in increments of one to “0,” to provide a wide range of volume settings. Two small toggle switches between the display and the Volume knob let you reverse the output phase and mute the PRE550A. A small light below each indicates when the function is turned on. All of the PRE550A’s front-panel functions are duplicated on its remote control.
The remote control isn’t the heaviest I’ve used, but at 9.25” it may be the longest. It’s actually a universal control that works with all YBA models; to use it with the PRE550A, first press the button labeled Amp. Unlike some other metal remotes I’ve used, YBA’s has smoothly rounded edges. You’ll appreciate that if you drop it on your coffee table -- or your foot.
The asynchronous USB 2.0 connection for a computer requires a driver if you’re running Windows, but not with a Mac or Linux computer. No big deal -- that’s true of most high-resolution DACs. Inside the PRE550A are two Cirrus Logic CS4398 DAC chips. A small switch on the rear panel next to the AirPort Express device turns the digital section off to minimize noise. The internal DAC plays PCM files up to a word length of 24 bits and a sampling rate of 192kHz. Unless they’re first converted to 24/192 PCM streams, or below, which many servers can do, the PRE550A can’t play Digital eXtreme Definition (DXD) files (352.8kHz PCM) or Direct Stream Digital (DSD) files, though such files are still somewhat rare. Whether that’s important is up to you; personally, I’ve vowed to avoid all arguments about religion, politics, the audibility of Ethernet cables, and the sonic advantages of DSD.
The analog section has three inputs -- one balanced (XLR), one unbalanced (RCA), and one video pass-through (RCA). The analog inputs have an input impedance of 10k ohms, which should work with most solid-state units, but might be too low for compatibility with tube units. There are two sets of RCA outputs and one set of XLRs. The output impedance is less than 56 ohms, which should have no trouble driving any amplifier I know of.
The PRE550A is warranted for three years, parts and labor; reasonable for a product at this price. US warranty service is performed in Chicago; a defective unit won’t have to go back to France for service.
Setup and use
The single-chassis Passion PRE550A slid easily onto a vacant shelf on my equipment rack. I used High Fidelity Cables unbalanced interconnects to connect the PRE550A to my amplifier, and CablePro Freedom unbalanced interconnects to link it to my JL Audio Fathom f110 subwoofer.
I tried the PRE550A with several sources: a dedicated server, a computer-based server, a CD transport, and an analog source. For the computer setup I used the Roon server program running on my Hewlett-Packard Envy laptop. Although the PRE550A doesn’t play DSD files, Roon does a fine job of converting DSD to PCM on the fly, so once I’d set up Roon to make the conversion, I could play DSD files. Remote control of the server was provided by the Roon Remote app running on my iPad Air 2. Downloading and installing the Windows driver was easy and quick. For the dedicated server, I used an SOtM sMS-1000SQ with its sMS-1000 power supply.
Thanks to its easy-to-use Linux-based software suite (Vortexbox and Logitech Squeezebox Server), the SOtM has become my server of choice. Like Roon, the SOtM does play DSD files, and can be adjusted to convert DSD files to PCM. Since the SOtM has a particularly high-quality USB output card, I used the same Audience Au24 SE USB cable for both the computer and SOtM servers, though not at the same time. And I connected my vintage Meridian 500 CD transport with an Audience Au24 SE S/PDIF cable. Although its recommended load impedance is greater than 10k ohms, I used my Sony XDR-F1HD tuner, modified by Radio X Tuners, as an analog source, connected to the PRE550A with Crystal Cable Piccolo unbalanced interconnects. The PRE550A had already been broken in, but I played it a while, getting used to it before I began my critical listening. This gave me a chance to listen to lots of different music, which is the fun part of reviewing.
Along with the PRE550A, tmh audio sent an Audio Art Cable Statement 1 power cord (1.5m, $1030), which they highly recommend for use with the PRE550A. It doesn’t seem unreasonable to use a $1030 power cord with an $8000 line stage. The cord was solidly built, using Furutech carbon fiber-bodied plugs with rhodium-plated metal contacts. I was tickled to see a distributor pay attention to the power cord; all too often, I get something that looks like a $3 computer power cord. That’s why my reviews normally use a third-party power cord; junk power cords can prevent some equipment from sounding its best. Although the Audio Art cord was already broken in, I gave it lots of playing time to relax after its shipment.
Everything was connected, and I was ready to turn on the PRE550A. But wait -- where’s the power switch? After a search, I found it on the bottom plate, directly below the Source label. Users are sternly warned to turn off the power before connecting or disconnecting source components or amplifiers to the PRE550A. I complied.
As expected, the PRE550A was quiet as a tomb. Hold on -- bad simile. I’ve never been in a tomb, and hope to stay out of one for some time. Nonetheless, the YBA was utterly quiet. The highest volume setting I used was “-23,” in the range from “-80” to “0,” for a very low-level recording -- there was a substantial reserve of volume left. Although it freely rotates, the volume control felt solid, with a bit of resistance to keep you from accidentally changing the setting. In use, the PRE550A felt as nice as it looked.
The Sony FM/AM tuner sounded fine through the PRE550A. I wasn’t listening critically to the tuner, only using it to see how an analog source worked with the PRE550A. The remote source selection requires that you cycle through all sources, even those with nothing plugged into them. After I’d listened to the tuner a bit, I shifted through the sources back to the USB input, which began playing with no problem.
During my listening, I committed the faux pas of turning off the PRE550A before turning off the power amp. I feared I’d hear a massive thump, but all I heard was -- nothing. Complete silence. Whew! YBA helped me avoid what could have been a nasty situation.
The first source I critically listened to was the SOtM server. If I had to use a single word to describe the PRE550A’s sound, it would be beautiful. It had a harmonically complete, suave character. Dynamics were powerful, yet subtle when required, and fast. The quietness I’d already noted let me hear a lot of detail -- real detail, not the fake detail created by goosing up the high frequencies. Speaking of the highs, they were open and extended, with plenty of sparkle. In “The Panther,” from Jennifer Warnes’s The Well (16-bit/44.1kHz WAV, Sin-Drome), the assorted percussion instruments near the beginning of the track sounded extremely detailed with abundant high frequencies, but with no trace of peakiness. At the other end of the spectrum, with Folia Rodrigo Martinez, from Jordi Savall’s La Folia 1490-1701 (16/44.1 WAV, Alia Vox), the deep bass drum had fairly deep extension, though with a smidgen less impact than I sometimes hear. But the bass was taut, without bloom or sloppiness.
In the überimportant midrange, Savall’s viola da gamba sang out beautifully, with fully developed harmonics, and the sounds of the woodblocks, cascabels, and other percussion instruments were very clear, with well-defined initial transients and decay. The clatter of percussion was much more prominent than usual, which kept their sounds from receding into the background. The instruments were naturally placed within the soundstage, which spread evenly between the speakers. Overall, I heard a natural, organic sound that ever so slightly emphasized the high frequencies.
Orchestral instruments had lots of clarity in James Horner’s (yes, the composer of the Titanic film score and many others) Pas de Deux, a concerto for violin and cello performed by violinist Mari Samuelsen and cellist Hakon Samuelsen, accompanied by the Royal Liverpool Philharmonic conducted by Vasily Petrenko (24/96 AIFF, Mercury Classics/HDtracks). Orchestral color was just gorgeous, with fully developed harmonics making the RLP sound rich and natural. I recently auditioned a DAC that made it difficult to distinguish between the solo violin and cello. The PRE550A had no such problem. Orchestral violins had a rich sheen, with abundant high-frequency extension. Bass drums didn’t display the utmost in bass extension, but provided the foundation of the orchestral sound with natural-sounding impact.
“Texas Rangers,” from Rebecca Pidgeon’s Four Marys (24/96 AIFF, Chesky/HDtracks), showed her in very expressive voice, with tons of detail that let me visualize her enunciating each word. The banjo and fiddle accompaniment sounded particularly realistic. Pidgeon’s voice was spread across the soundstage, not pinpointed at a specific location.
Allegri’s Miserere, in the a cappella recording by the Tallis Scholars (24/96 FLAC, Gimell), is a favorite for soundstage evaluation: at the front of the soundstage is the main choral group, and some distance behind them a smaller group. Ideally, the smaller group is immersed in a reverberant soundfield that makes clear its distance from the main group. Through the PRE550A, this smaller group was obviously singing in a different part of the large venue; the reflected sound was pristinely clean and uncongested, but sometimes the smaller group sounded a bit smeared and distorted. The main group sounded focused and firmly placed on the broad soundstage. The overall sound was brighter than I’m used to, but not excessively so.
To hear how the YBA reproduced a solo instrument, I cued up Ottmar Liebert’s One Guitar (24/96 FLAC, Spiral Subwave/HDtracks). The detailed realism the YBA PRE550A retrieved from this high-resolution recording was amazing. It reproduced the sound of Liebert’s guitar incredibly well -- not only the notes, but also the extraneous noises inevitably produced by a guitar being played by a master. Notes were harmonically complete, attacks and decays were extremely lifelike, and some of the initial transients were startling in their forcefulness. The soundstage seemed slightly more diffuse than usual, however.
I set up my computer-based server with Roon driving the PRE550A and converting DSD files to PCM. It didn’t sound greatly different from the SOtM server, so I’ll focus on areas where they did sound different. With Horner’s Pas de Deux, orchestral harmonics were also rich, but perhaps very slightly less smooth. In Folia Rodrigo Martinez, bass was slightly more extended but no more impactful. There was lots of detail in the percussion, the woodblocks’ harmonics sounding particularly realistic. In Allegri’s Miserere, the distant solo group sounded just slightly more detailed, its sound remaining embedded in the reverberant field that created the sense of depth. The main chorus up front had just as much spread within the soundstage, but with slightly less continuity in the side-to-side image.
One Guitar, on the other hand, sounded slightly more focused, with lots of dynamic differentiation. There was still a lot of “startle” factor. The PRE550A was sufficiently transparent to make it easy to distinguish between the two digital servers. It wasn’t starkly analytical -- if anything, it was the antithesis of that.
Switching to the Meridian 500 CD transport, which I hadn’t used in a while, reminded me of what a pain it is to play CDs; not nearly as much as LPs, but close. Some of that was my fault -- since I’ve started using a server as my principal source, I haven’t been nearly as careful about filing CDs as I used to be. Maybe I should describe my actions as “piling” rather than “filing.” Also, many of the musical selections I currently use in my evaluations are high-resolution downloads for which I lack CD versions. Another factor: the S/PDIF cable had seen little use, and so probably wasn’t broken in. Most of my sources have only USB outputs.
With Jennifer Warnes’s recording of “The Panther,” high frequencies were considerably more rolled off. Percussion instruments, which had exhibited abundant high-frequency extension, seemed much less audible. To check whether the S/PDIF cable might be at fault, I tried a well-broken-in Wireworld Gold Starlight 5 AES/EBU cable and heard the same rolloff. Not only was the treble affected; with Folia Rodrigo Martinez, bass seemed a lot more powerful than from the SOtM server. In fact, I couldn’t recall having heard the bass drum reproduced with such extension and impact. Percussion transients were less defined, but oddly, the opening cascabels were detailed, with perhaps a smidgen less HF information than usual. Savall’s viola da gamba seemed less tonally rich than through the servers.
My standard setup comprises an Audio Research SP20 preamp ($9000), PS Audio DirectStream DAC ($5995), and Clarity Cables Organic interconnects ($1400/1m pair): a total of $16,395, or more than twice the cost of the YBA. Unlike the Passion PRE550A, the SP20 is a full preamplifier with an excellent phono section and a really decent headphone amp, uncommon for ARC. The PS Audio DAC plays DSD in native mode using the DSD over PCM (DoP) protocol. In fact, the DirectStream converts everything to DSD before converting it to analog.
I’ve already compared the sounds of different sources and found the computer-based server running Roon sounded comparable to the others, so here I focus on how that server sounded with my reference system. The strings in Horner’s Pas de Deux sounded almost lush, and quite smooth. The bass in Folia Rodrigo Martinez extended deeper, with more impact and power. It didn’t shake the room, but the difference wasn’t hard to hear. Details were abundant in the midrange and treble, and, as with the other sources, percussion instruments were especially realistic. The choristers’ voices in Allegri’s Miserere sounded slightly smoother, with good but not outstanding focus and localization. The distant solo group was just slightly less detailed than through the PRE550A. Finally, Liebert’s One Guitar showed plenty of dynamic variations, but I got the impression that the guitar had a smidgen more power in reserve. Harmonics were quite realistic, with slightly less HF extension than the PRE550A. I slightly preferred the PS Audio-ARC-Clarity combo, but remember -- they cost more than twice as much as the YBA PRE550A, and the differences weren’t major. I prefer a DAC that can play DSD files without converting them to PCM, and can play DXD files (24/352.8 PCM) -- but neither of those may be important to you.
YBA’s Passion PRE550A lived up to its French origin by producing unfailingly beautiful, realistic sound. Its extended highs were gorgeously smooth, with nary a bit of peakiness. The midrange was very detailed and harmonically rich -- little to grumble about there. I found the YBA’s soundstage slightly less than pinpoint precise, but some might prefer its greater width. Within its limits of 24/192 PCM, the YBA was very flexible, with plenty of digital inputs available for just about any digital source imaginable. And although it won’t play DSD files, I greatly enjoyed listening to the way the PRE550A played converted DSD files. And the YBA has enough analog inputs to make it truly useful as the center of a serious hi-fi system.
The Passion PRE550A looked and sounded gorgeous, is built like a brick privy, has a thoughtfully designed remote control, and no significant vices. I could, and did, happily live with a PRE550A in my system. Very highly recommended.
. . . Vade Forrester
- Speakers -- Affirm Audio Lumination, JL Audio Fathom f110 subwoofer
- Amplifier -- David Berning ZH-230
- Preamplifier -- Audio Research SP20
- Sources -- Meridian 500 CD transport; Hewlett-Packard Envy laptop computer running 64-bit Windows 7 Home Premium and RoonServer software; SOtM sMS-1000SQ server and sPS-1000 power supply; PS Audio DirectStream DAC; Sony XDR-F1HD AM/FM tuner (modified by Radio X)
- Interconnects -- CablePro Freedom, High Fidelity Cables, Clarity Cable Organic, Crystal Cable Piccolo, Wireworld Gold Starlight 5 AES/EBU
- Speaker cables -- Clarity Cable Organic
- Power cords -- Audience powerChord e and Au24 SE LP powerChord, Audio Art Cable Statement 1, Blue Marble Audio Blue Lightning, Clarity Cable Vortex, Purist Audio Design Venustas
- Digital cables -- Audience Au24 SE USB and Au24 SE S/PDIF
- Power conditioner -- Audience aR6-T
YBA Passion PRE550A DAC-Preamplifier
Price: $8000 USD.
Warranty: Three years parts and labor.
PO Box 751681
Dayton, OH 45475