Burson Audio - Conductor SL 1793 - Headphone Amplifier and DAC

Even though these aren't made anymore, they are great AMP/DACs for the price and this is my second one.

It’s surprising to me how little buzz there is surrounding this amp / DAC combo, especially considering the popularity of Burson and their Conductor line in particular. I had literally not even heard of the Conductor SL before it went on sale for HALF its retail price a few weeks ago. Needless to say, I had to jump on that. Now after having used it extensively for close to three weeks, I can honestly say that I might have stumbled onto the deal of the year with this one.The Conductor SL actually comes in two different flavors: the 9018 which contains a newer DAC based on the 32bit capable Sabre32 chipset, and the 1793 which comes with the older 24bit Burr Brown PCM 1793. There are a couple of really good articles comparing the two DAC options, so I won’t go into the differences here considering I have not heard the 9018 version yet. In the future, I hope to purchase the Sabre32 DAC (one advantage of the SL being that you can easily swap the two boards) so I can get a good A/B going, but for now I’ll just have to defer to the general consensus regarding their sound characteristics. The 9018 is generally described as more detailed and analytical, while the 1793 is considered the more musical of the two.Build quality is absolutely top notch, and I’m going to keep this section fairly utilitarian so as not to drag things out. It’s got a nice brushed aluminum chassis and sturdy components. Getting into its insides has also been made remarkably easy to accommodate those who want to switch out DAC’s. It’s as simple as loosening a few screws. There are two gain settings, low and high. If there is any audible noise to be had, then I could not detect it EXCEPT when using my Westone W30’s on the high gain setting. That’s basically a non-issue, though, considering they become blisteringly loud even on the low gain setting. There are ins for Toslink, USB and RCA. At 2W into 8ohms I never really felt the amp section struggle to power any of my headphones. Perhaps a ridiculously difficult to drive headphone like the HE6 would benefit from a more powerful amp section, but even with the HE560’s I did not feel like there was a shortage of wattage.(Unless otherwise stated, I did most of my listening with a “production” pair of HE-560’s with roughly 200 hours of usage.)Again, I can’t speak on the sound of the 9018 yet, but I have to agree that the 1793 does indeed lean toward the “musical” side of the sound spectrum. The lows in particular are just fantastic. Sub-bass performance is some of the best I have heard in this price range, hitting deep and hard, but never becoming bloomy or overpowering. Then into the mid and upper bass you get a very nice, powerful, guttural growl and punch that you can’t help but love to hear from bass guitars and bass drums. It may be perhaps a bit too forward for folks looking for a more neutral presentation, but in all honesty, I can only make that claim in comparison to more analytical amps and DAC’s. My Lyr / Bifrost, for instance, presents lows more neutrally, but I’ve always felt like it was a tad boring for most of the music and games I listen to. The SL 1793 is nice and warm and cozy sounding on the low end, which I think is the main attribute contributing to folks describing it as “musical.” I can’t really disagree with them.I was also pleasantly surprised with the mids. With the HE560’s, the mids, while certainly not lacking, tend to be slightly recessed compared to the lows and highs. The SL 1793 did quite a bit to bring the mids more forward; from three rows back, to one row back, if that makes sense. Indeed, I noticed that the mids were brought slightly forward with most of my headphones. I have generally found that this is never a negative for me. Even with my LCD2’s which already have pretty forward mids, the extra little step up just made me appreciate mids that much more. I guess I’m just a mids man. Like the lows, I would not say that they are ever overpowering in any way. In fact I think the DAC as a whole is slightly “U” shaped (SLIGHTLY) in that the lows and highs are a bit more prominent overall. But where a lot of amps, DACs and headphones tend to turn a blind eye relative to the rest of the spectrum, the SL 1793 shows some tender love to the mids as well, and I really appreciate it for that.Highs are the one area where I think the SL 1793 is marginally less successful. Most reviews seem to suggest that this is a “warm” amp /DAC, but the highs tend to bely that assessment. With certain headphones, there is a bit of stridency that I just cannot handle. My HD800’s would otherwise sound fantastic out of the SL if it weren’t for the constant sibilance it brings in the upper registers. Vocals in particular seem to suffer from an unnatural wispiness thanks to this spike. There is a similar effect with my Q701’s and T1’s. So I don’t necessarily recommend this amp to pair with headphones that have pronounced highs, but I have to say with darker headphones that extra treble energy really, really shines. My LCD2.2’s sound absolutely fantastic out of the SL. The pairing even surpasses the Lyr / Bifrost by a large margin in my opinion, which is a pretty well regarded setup for the LCD2 to begin with. The 560’s sound fantastic too, even with the slight treble edge they have over most other planar magnetics. So it is by no means a glaring flaw. It’s just important to understand that this is NOT a dark sounding combo like the Violectric line, or an OTL tube amp.Detailing is also wonderful. I get a clearer, more detailed and spacious sound than I do from the likes of my G109 / Lyr amps paired with my Uber Bifrost. This might all be relative though, considering the price difference between the two setups. It has been said that the 9018 is a much better performer in the areas of clarity and detailing than the 1793, but for my money the 1793 does very, very well in its own right. Soundtaging, too, is one of its strengths, though I am probably not the best judge of that. I can definitely hear that the sound is slightly more open and airy than the Lyr / Bifrost (I think because of the extra treble energy and clarity), but even between headphones the only time I can detect large differences in soundstage is when switching from closed to open headphones. So, that I can even detect that the SL is fairly large at all might be a testament to its superiority in the category, but I will save any definitive statements for reviewers that are more capable of accurately evaluating this characteristic. For what it’s worth, it is the most “open” and spacious sounding amp / DAC I have ever heard, though not by any degree that I would consider significant.So if it hasn’t become glaringly obvious over the course of this review, I absolutely love the Conductor SL. The 1793 version is just a very fun, musical, capable amp that I can’t help but recommend. At $1200US, you’re looking at a pretty heavy investment, but even the cheaper, still-well-regarded combos like the Uber Bifrost / Lyr cost close to a thousand bucks when all is said and done, and honestly I think the Conductor SL1793 leaves that combo in the dust for most applications. Needless to say, at roughly $600, it is far and away the best deal I have ever stumbled across in this increasingly expensive world of headphones and headphone accessories.

Burson says that the Conductor SL "is the best amp / dac in the world."' I couldn't agree more. The soundstage is huge. The bass and upper bass is very well controlled with my Sennheiser's. Midrange is airy with plenty of separation. There's a hint of delicacy in the treble that is quite amazing. The 1793 dac is a little bit on the warm side so just be aware of that when matching your headphones.