As an audiophile always on the lookout for gear that offers exceptional value, I was excited to get my hands on the new Fiio K11 R2R DAC/Amp. This updated version of the popular K11 promises to bring the warmth and musicality of R2R (resistor ladder) DAC technology to a more accessible price point. In this review, I'll share my experiences with the K11 R2R and explore whether it lives up to the hype.

Unboxing and First Impressions

When I first received the Fiio K11 R2R, I was impressed by the comprehensive package. Inside the box, I found:

This complete set ensures you have everything you need to start using the K11 R2R right out of the box, which I always appreciate.

Build Quality and Design

As soon as I picked up the K11 R2R, I noticed its robust build quality. The aluminum shell gives it a premium feel that belies its budget-friendly price point. Fiio offers the K11 R2R in both black and silver options, allowing users to choose the one that best fits their setup aesthetics.

One of the standout design features is the simple interface, controlled by a single push knob. This knob handles both volume adjustments and menu navigation. I found the knob to have a nice tactile feel, providing smooth operation with just the right amount of resistance.

All components of the K11 R2R feel flush and well put together. It's clear that Fiio has paid attention to quality control, as every unit I've come across has exhibited the same level of build quality.

The compact footprint of the K11 R2R remains unchanged from its predecessor, making it perfect for users who need a powerful amp with minimal desk space. This is particularly useful for those with crowded workstations or small living spaces.

One minor gripe I have is with the LCD screen on the front of the unit. While functional, I found it a bit small and sometimes difficult to read. However, given the compact size of the amp, this is a trade-off I'm willing to accept.

Technical Specifications and Features

The main difference between the original K11 and this new R2R version lies in its R2R ladder transistor array and R2R chip. For those unfamiliar with R2R technology, it's known for providing a warmer, more analog-like sound compared to traditional delta-sigma DACs.

The K11 R2R boasts impressive technical specifications:

- True 24-bit decoding

- DSD256 support (requires setting the DSD output mode to Native on the source device)

- Under a 320Ω load, it delivers 1300mW + 1300mW power output with the balanced connection

- THD+N of 0.025% (1kHz/-11.6dB@32Ω)

- Ability to drive headphones up to 350Ω impedance

I appreciate the inclusion of multiple input options, including RCA, USB-C, and Coaxial, as well as RCA outputs. This versatility allows the K11 R2R to fit into a variety of setups.

One neat feature is the LED logo that displays the current bit rate of the audio being streamed. It's a small touch, but one that I found quite useful for confirming the quality of my audio source.

Performance and Sound Quality

Now, let's dive into the most crucial aspect of any DAC/Amp – its sound quality. I tested the K11 R2R with a variety of headphones, including the Audeze LCD-2, a handful of IEMs, Hifiman HE1000 SE, and the notoriously power-hungry Sennheiser HD800s

Power Output and Driving Capability

I was impressed by the K11 R2R's ability to drive demanding headphones. With the Audeze LCD-2, I rarely needed to push the volume past 50% on high gain mode. Even the HD800s, known for being difficult to drive, posed no problem for the K11 R2R. This robust power output makes it a versatile choice for a wide range of headphones. The IEMs and HE1000 SE were completely able to be driven by the R2R.

Soundstage and Imaging

The most immediate difference I noticed between the K11 R2R and its predecessor was in the soundstage and imaging. The R2R version presents a more immersive soundstage, with impressive width and height that surpasses anything I've heard in this price range for integrated amps.

However, this comes with a slight trade-off in imaging clarity. Due to the added emphasis on low frequencies, the R2R has slightly less precise imaging than the previous iteration. That said, what it lacks in pinpoint accuracy, it more than makes up for in overall staging and immersion.

Tonal Balance and Character

The K11 R2R exhibits a slightly warmer overall sound signature compared to the original K11, which was known for its transparent and flat response. However, the difference is subtle rather than drastic.

I found the highs to be smoother and more organic on the R2R version. There's less of a digital character to the treble, resulting in a more natural and less fatiguing listening experience. This characteristic makes the K11 R2R particularly enjoyable for long listening sessions.

The midrange retains much of the clarity and detail of the original K11, but with a touch more body and warmth. Vocals and midrange-focused instruments benefit from this slight coloration, sounding rich and engaging without becoming overly lush or bloated.

In the bass region, the K11 R2R delivers a solid performance. The low end has good extension and impact, with a slight emphasis that adds to the overall warmth of the sound signature. However, it doesn't overpower the rest of the frequency range, maintaining good balance and control.

Comparison to the Original K11

While the differences between the K11 R2R and the original K11 are noticeable to discerning ears, they're not night and day. The R2R version offers a slightly warmer, more organic sound with a more expansive soundstage. However, it trades a small amount of analytical precision for this more musical presentation.

The original K11 might still be preferred by those seeking the most transparent and neutral reproduction possible. However, I find the R2R version to offer a more engaging and enjoyable listening experience overall, especially for those who listen to a wide variety of music genres.

Versatility and Pairing

Throughout my testing, I found the K11 R2R to be a versatile performer that paired well with a variety of headphones. Its slightly warm character complemented analytical headphones like the HD800s, adding a touch of musicality without obscuring detail. With warmer headphones like the Audeze LCD-2, it enhanced their inherent qualities without pushing them into overly lush territory.

The K11 R2R also performed admirably as a standalone DAC when paired with other amplifiers. Its DAC section maintained the same warm, organic character, allowing users to benefit from the R2R sound even if they prefer to use a different amplifier.

Value Proposition

At its price point, the Fiio K11 R2R offers exceptional value for money. It brings R2R technology, typically found in much more expensive units, to a more accessible price range. The combination of its robust build quality, versatile connectivity options, powerful output, and engaging sound signature makes it a compelling option for both newcomers to the audiophile world and experienced listeners looking for a compact, all-in-one solution.

Conclusion

After spending considerable time with the Fiio K11 R2R, I can confidently say it's an excellent piece of budget audiophile gear. Its ability to drive headphones up to 350Ω makes it a perfect match for popular options like the Sennheiser HD600 and Beyerdynamic DT770 250Ω. As users progress in their audiophile journey, the DAC mode ensures the K11 R2R can continue to serve as a capable source when paired with standalone amplifiers.

The K11 R2R's standout feature is undoubtedly its expansive soundstage, which outperforms many competitors in its price range. This, combined with its smooth, organic sound signature, makes for an engaging and enjoyable listening experience across a wide range of music genres.

While it may not be the last word in analytical precision, the K11 R2R offers a more musical and immersive presentation that I believe many listeners will prefer for long-term enjoyment. Its slight warmth and fuller body make it forgiving with less-than-perfect recordings while still retaining enough detail to satisfy critical listeners.

For those new to the world of high-end audio, the Fiio K11 R2R represents an excellent entry point. It offers a taste of what more expensive R2R DACs can do, wrapped in a compact, well-built package with enough power to drive most headphones on the market. Even for more experienced audiophiles, the K11 R2R could serve as a capable secondary system or an introduction to R2R technology without breaking the bank.

In conclusion, the Fiio K11 R2R DAC/Amp punches well above its weight class, offering a compelling blend of performance, versatility, and value. Whether you're just starting your audiophile journey or looking to add an R2R flavor to your existing setup, the K11 R2R deserves serious consideration. It's a testament to Fiio's commitment to bringing high-quality audio to more accessible price points, and it sets a new standard for what we can expect from budget-friendly audiophile gear.