TLDR; Stack to stack, the Benchmark has greater resolution and clarity, resulting in more detail across the whole spectrum, while the RME has a fuller bodied, more saturated sound with wider staging. Although I prefer the sound of the Benchmark, the RME is absolutely the best value in audio I've yet experienced. While $2500 might be a lot, it's the cheapest I've seen for a DAC/amp combo that is amazing at every category of sound and can drive nearly everything. It simply has no shortcomings, no omissions, and no weaknesses, something I cannot even say about the Benchmarks. Add on its DSP features, its tiny footprint, its AIO format, its ADC capability, etc., etc., and it simply can't be beat for price to performance.
Mostly, the differences between the two are rather small, and it's only in direct comparison to the Benchmark stack that the RME sounds like I'm describing. Taken in isolation, the RME is very clean, while maintaining a full sound. It has excellent resolving ability and imaging, and an expansive soundstage.
In the bass, the RME has less impact, but more presence and bloom, giving the bass a fuller feel to it. The bass lingers around longer. The Benchmark has more control, allowing the bass to be isolated by the ear more readily, while also having more focused impact to each bass note. In the mids, the RME doesn't quite manage the instrument separation, layering, and control that the Benchmark has. On the LCD-5, my most difficult to drive headphone, the mids become a bit glaring and harsh, characteristics they don't show when played through the Benchmark. For both treble and mids, the RME isn't as detailed, especially when it comes to perceiving room effects or subtle positional cues. While the RME does seem to have a wider soundstage, it renders less specific imaging. Also, it seems to blunt the decay and reverb trails of sounds. This gives a greater sense of black background, but it doesn't sound as natural. Sort of like turning up the contrast in an image. This also negatively effects the shimmer of cymbals, especially in busier passages.
When paired with the ZMF Atticus, a headphone that I personally find sensitive to amps, the RME sounded better subjectively that the Benchmark. It sounded lusher and more inviting, softened the too bassy FR some, and expanded the soundstage out quite a bit. I enjoyed the Atticus more with the RME than any other amp I've tried, even tube amps. On the other hand, the LCD-2C came off as a slightly muffled, flabby in the bass, and kind of lifeless through the mids on the RME, which is definitely not my experience with the Benchmark. Gone was the impactful but clean bass and detailed mids. This was the worst pairing with the RME. The Arya v2 was an interesting case, as it sounded quite different between set-ups, but it's hard to say which one I ultimately prefer. With the RME, it gained some much needed warmth and fullness in the low-end and lost a little of the crispy, metallic edge it can sometimes have. On the other hand, the Benchmark, as with all my headphones, wrung out the very last bit of detail, control, and clarity. Both takes on the Arya were excellent.
As a standalone DAC, the RME wins easily, but for a weird reason. The Benchmark DAC outputs 24v at line-out, making its ouput out-of-spec many amps (this is the reason I wanted another DAC in the first place). So, I had to compare RCA out on the DAC-3B to XLR output on the RME. With my WA22 as the amp, that was an easy victory for the RME. It just sounds more dynamic and resolving, plus I could use all the DSP adjustments on the RME to tailor the output. It's possible that this all comes down to the difference in inputs on the WA22, rather than the outputs on the DACs, but I can't verify that one way or the other.
For sensitive IEMs, the differences were hard to discern. Also, I am frankly unlikely to use either over my DAP, for practical reasons and for sound quality. Given a choice, I would choose the RME for its more IEM-friendly 4.4mm output (over the Benchmarks XLR).
As a wrap up, I love both the RME and the Benchmark stack, but I give the RME the higher recommendation because in addition to its spectacular sound quality, it is ridiculously versatile. Seriously, it is the only DAC/amp worthy of being called an
all-in-one. Nearly everything else is frankly just a
two-in-one.
. Anyone can contact RME support to ask them outright if the linear supply will improve anything, and here it straight from Rme if you wish to be sure. In the usa it is Synthax in FL. They are very helpful.
