Affordable and Transparent: The OPPO HA-1 Headphone Amplifier/DAC
WHAT DO WE HAVE HERE?
My previous review here on InnerFidelity was a large black box with a forest of vacuum tubes rising up from its surface, and nary a digital function to be found. Almost diametrically opposed to that, the Oppo HA-1 ($1199) took up residence immediately thereafter in my review cuegleaming silver, LCD display, remote control, and as modern an integrated DAC/Headphone amp as one could imagine. And yet at the risk of spoiling the surprise, or lack thereof, I will tell you that the Oppo is also outstanding, and represents somewhat of a bargain. More on that later.
The HA-1 is pretty loaded with features. Loads of inputs and outputsoptical and coaxial digital, XLR and RCA analog, USB DAC (of the better Asynchronous type), and a USB input on the front meant for an iOS device. I used this input with my iPad quite a bit and that worked very well. The included remote control provides basic transport functionality for iOS devices in this mode. Headphone outs are both unbalanced RCA and balanced 4-pin single XLR. Power output for the headphone amp was ample for my Audeze LCD-3 headphones, which were what I used primarily for this review. The Oppo's LCD display aids in source selection and some other menu functions, and then will provide either a spectrum analyzer or VU meter display while listening, which I found to be very fun and cool. If you don't like it though, you can turn it off.
Build quality is pretty impressive as well. The unit is heavy and solid, and looks very nice. The DAC chip used is the ESS Sabre 32 Reference, which is very highly regarded, although like everything it has its detractors. I am not one of themI own an Oppo BluRay player that uses the ESS DAC and its sound quality has always impressed me. It supports pretty much any digital data rate you could reasonably want to use, which uncommonly includes DSD 64, 128, and 256 (although I was unable to test this). Technically speaking, its all the DAC one could ever really need.
THE SOUND OF NOTHING
OK, OK, so it's got a lot of cool technology and it looks neat. None of that would matter a hoot if it didn't sound good, that's for sure. Well I'm happy to report that the HA-1 sounds better than good. It sounds terrific. I have been able to review a pretty large number of high-end headphone amps over the years, and typically what I find is that while they all have some great strengths, they also have a few things I wish they did differently. In the case of the Oppo HA-1, that wasn't true. The words I kept thinking of during my listening were "balanced", "neutral", "even"...this is really what I get from the Oppo.
When I listened for details, they were all there, in spades, and I didn't have to work hard to hear them. But they were not pushed at me, and I never felt the treble was unnatural, which will sometimes provide a false sense of an amp being detailed. There was no unwanted etch or unnatural vocal sibilance. I don't think anyone would ever describe the Oppo's sound as laid back, though, and if you want an amp to tame an aggressive headphone, the HA-1 is NOT the one to get. But with a good headphone that doesn't need "correcting", the balance between treble presentation and smoothness is excellent. The treble is very clean, with no grain, but it's not in any way rolled off or shelved down. The HA-1 also really feels like it has limitless top end extension, something much more expensive headphone amps do not always accomplish.
A good example of this comes from the song "Carie" from the Spock's Beard album "Snow". The cymbals are not high in the mix in this song, but through the HA-1 you can hear them and their delicacy, without causing the acoustic guitar to sound etched or strident. In fact the guitar sounds incredibly natural, as do the cymbals, which isn't always an easy trick to pull off. Yet the HA-1 does this effortlessly.
The bass is also spot on. There is plenty of bass weight and extension when called forreally as much as one could ask for. I never wished for more bass weight, but I never felt the bass was overweight either. Plenty of amps have bottoms that are just plain too big, but not the Oppo. It was just right. One of my favorite bass test tracks is "Russia On Ice" from Porcupine Tree's phenomenal "Lightbulb Sun" (if you like progressive rock even a little bit and you don't have this album, run and buy it). The 96/24 version of this album from the DVD-Audio is just stupendously good sounding, and this track has some of the heaviest, deepest bass around. The Oppo nailed it, providing not only great bass weight and extension, but at the same time, excellent bass definition. Attack and decay were impressive. "Russia On Ice" is a sinister song, and if the bass isn't right, some of that sinister feel is lost. Here, it was downright spooky!
And then there is the midrange. Here I don't exactly have a nit to pick, but perhaps more of an observation. The Oppo favors transparency over lushness in the midrange. The mids are certainly clean, clear, and balanced within the overall presentation. There wasn't ever a time when I felt there was something missing or awry. That said, the Oppo simply doesn't provide the kind of bloom in the mids that a good tube amp will. Is that because tubes color the mids? Maybe in a waynot in terms of frequency response, but in terms of something else, possibly. The best tube amps can provide a sense of breathtaking lushness to the midrange that the HA-1 doesn't have. What the Oppo does have is a breathtaking sense of clarity to the mids. And in the context of the rest of the sound, this works, and works well. The midrange presentation helps to contribute to the overall sense of a very balanced presentation that the HA-1 has.
I want to make it plain that I do NOT consider the midrange of the HA-1 flawed or problematic. Far from it. But if your listening preference is for something on the lush side, that's not what you will find here. The HA-1 is for the crowd that wants no editorialization whatsoever from the amp. There are plenty of audiophiles that say they want that from their amp, but when it comes right down to it, they don't actually buy amps that prove it. The HA-1 will let you hear exactly what your headphones sound like on their own. So you better make sure you like your headphones! The Oppo isn't a "synergy" kind of amp. It's much more about presenting the truth. But please, dear reader, do not assume that what I mean here is that the HA-1 is bright. It's not bright. It's neutralspot on neutral. Listening to Mastodon's "Curl of the Burl" from "The Hunter" never caused me to wince, and trust me, when the system isn't right, it will do that. Instead I could crank it up and really enjoy doing so.
So the HA-1 isn't lush, but can there be beauty in an amp with a truly neutral midrange? You bet. Listening to Transatlantic's fantastic cover of ELO's "Can't Get It Out Of My Head", the beauty was thrilling, and I got goose bumps big time. The same with Peter Gabriel's voice on "The Carpet Crawlers" from Genesis's "The Lamb Lies Down on Broadway". Again I got chills listening to this song played on the HA-1. Gabriel's voice was incredibly lifelike, and when you can plainly hear Phil Collins' terrific background vocals distinctly being behind Gabriel. Suzanne Vega's sultry "Caramel" was also rendered in a way that was almost alarmingly natural sounding. The same was true of Candace Night's voice on Blackmore's Night's "The Dancer and the Moon" from the album by the same nameher voice is high enough that if there is a problem in the mids it will sound harsh, but it was all pleasure and no pain with the HA-1. So yes, in many cases, I did find music via the Oppo to be beautiful. Sometimes amazingly so.
The soundstage presentation of the HA-1 was also first-rate. Width was outstanding, with the soundstage extending well outside the head from side to side. The soundstage is also a little out in front (and good thing), and had good depth. And image specificity was top notchI consistently felt I was getting all that the LCD-3 headphones could give me in terms of soundstaging, and frankly that's saying something, as I consider the Audeze exemplary in that regard. Soundstage freaks, the HA-1 will float your boat.
All of the above comments refer to the sound of the HA-1 as an integrated DAC/AMP. I did also try the HA-1 as just an amp, connecting the analog outputs of my Pioneer N-50 Network Audio Player to the analog inputs of the HA-1. Oppo makes a big deal about how the analog inputs are kept in the analog domain all the way through the HA-1. And the Pioneer DAC did sound a little different than the Oppo's. I was forced to admit, though, that if anything the DAC in the Oppo is a little better sounding than the one in my N-50. The N-50's 384/32 capable DAC I think is excellent, but the HA-1's internal DAC was just a little bit more transparent, I thought, and has just a little better apparent resolution. That said, the sound was just slightly warmer with the N-50 serving as the DAC. Very slightly. The HA-1's DAC is so good, though, that not only would I not want an external DAC if I were to own an HA-1, but I wouldn't hesitate to use the HA-1 as a stand alone DAC.
AND IN THE END
Speaking of owning one...I intend to buy the review sample if I can. I think the HA-1 is good enough to use as a reference, and in fact, because of its preternatural neutrality, it makes a good reference indeed. But more than that, I just plain enjoyed listening to music on the thing. And I enjoyed it frequently. I also enjoyed looking at it. In fact there wasn't anything about it that I didn't enjoy, and I guess that's really the highest compliment I can pay it. It's also very high on the value scale, competing very well with headphone amps that are in and above its price range that have no DAC at all. When you consider the whole package, the Oppo HA-1 definitely belongs on InnerFidelity's list of "Stuff We Like". I wouldn't recommend it to people who are looking for an amp to solve a "problem" they have with their headphones (and from what I read on several headphone boards this is a very common thing, sadly). But if you like your headphones and just want them to sound their very best, the HA-1 will deliver that, big time. Good stuff, indeed.