There are few things in the AV market right now that excite me quite so much as the melding of high-end two-channel audio with the latest in video connectivity. Let's face it: those of us who build wall of separation between our two-channel and AV rigs are dinosaurs at this point (though, in my defense, I mostly do so more out of habit, lifestyle, and the necessities of testing than anything else).
That's why a product like Krell's K-300i Integrated Stereo Amplifier makes my bits tingle. The K-300i undoubtedly follows from a tradition of two-channel excellence on Krell's part. The unit employs the company's proprietary iBias technology to deliver the sonic benefits of Class A operation without doubling as a space heater, and without the crossover distortion typical of Class AB designs. All in all, the K-300i delivers 150 watts RMS per channel into 8Ω and 300 watts RMS per channel into 4?.
The K-300i also boasts a respectable number of stereo inputs, including a pair of balanced XLR ins and a trio of single-ended stereo RCA inputs. The optional Digital Module, which tacks $1,000 onto the $7,000 price of the base analog integrated amp, adds a Toslink optical input (with support for PCM up to 96/24), a coaxial digital input (192/24), and a pair of HDMI 2.0/HDCP 2.2 inputs (and one output) with support for HDR10, Dolby Vision, Audio Return Channel, and 4K video up to 60Hz, as well as PCM up to 192/24 and DSD up to double-rate. The Digital Module also adds two USB inputs (one Type A and one Type B) and support for USB and network streaming of MP3, AAC, WMA, WAV, FLAC, and ALAC up to 192kHz, as well as Bluetooth with aptX, with support for A2DP, AVRCP, HFP, and HSP profiles.
In addition, the Digital Module unlocks connectivity via the mconnect Control app for iOS and Android, which adds support for vTuner Internet radio, Tidal, Deezer, and QoBuz. The K-300i with Digital Module is also a Spotify Connect device, is Roon Ready, and decodes MQA.
Aesthetically speaking, the K-300i shares a lot of DNA with Krell's Illusion II Preamplifier, save for the missing vertical cove in the front of its semi-cylindrical bulge, and the fact that its façade is monochromatic, either silver or black, not the two-tone design that dominates the rest of Krell's lineup. With dimensions of 4.12 by 17.25 by 18 inches (hwd) and a weight of 52 pounds, the chassis is beefier than it looks at first glance, mostly a result of its gargantuan power supply and husky internal heat sinks.
Being the binding-post fetishist that I am, the first thing I noticed about the K-300i upon unboxing it and prepping for installation in my two-channel room were its gorgeous, meaty speaker connections, which are designed to accommodate spades (5/16-inch), bare wire, or banana plugs, the latter being my preferred connector.
The back panel also includes an RS-232 port, an RJ45 Ethernet port (10/100), a RC5 3.5mm input for 5-volt IR from advanced control systems, and 3.5mm 12-volt trigger input and output.
Setup in my stereo system proved to be easy and straightforward. In my two-channel audio room, I primarily rely on my Maingear Vybe media and gaming PC as a source, with a USB connection. No driver installation was required on Windows 10, and I was up and running within minutes. Speakers in this system were a pair of GoldenEar Triton One towers connected to the integrated amp via a pair of ten-foot ELAC Sensible Speaker Cables.
Moving the K-300i into my bedroom AV system proved to be a little less plug-and-play. While the integrated amp does provide stereo preamp outputs, which can be used to drive a subwoofer, it offers no internal crossover for sub/sat situations. And my go-to subs for this system, a pair of RSL's Speedwoofer 10S, don't feature speaker-level outputs. So, I swapped in a GoldenEar ForceField 3 sub and a pair of RSL's CG25 LCRs. I connected the K-300's HDMI output to my old Samsung JS9000 UHD TV, ran my Oppo UDP-205 into one of its HDMI inputs, and a Roku Streaming Stick+ to the other.
In addition to the issues detailed above related to the operation of the K-300i in a 2.1 system, other potential aggrievances start to raise their heads when employing the integrated amp in an AV system. We'll touch on these in more depth in the Downsides section, but suffice to say here that the system's remote isn't well-laid out, and navigating its setup menus is less than intuitive. Another potential gripe is that the K-300i comes with CEC (Consumer Electronics Control) turned on, and indeed, CEC is required for Audio Return Channel functionality, but the amp doesn't actually used CEC for any control functionality. If you're connecting the unit to a display via HDMI and you're not using ARC, you should probably turn CEC off to avoid any errant input changes.
As mentioned above, though, the unit does support RS-232, IP, and IR control from advanced control systems and Krell provides a list of IP and serial command codes on its website. Unfortunately, I could not locate any pre-written drivers for Control4 systems, but Krell could conceivably develop those pretty easily to enhance the K-300i's appeal for dealers.
Setup and control issues aside, I found the Krell K-300i to be both a blessing and a curse in terms of its performance. A blessing, because it delivers some of the purest, least colored output I've experienced from any integrated amp. A curse, because, seriously, how in the hell do you describe the sound of a component that imparts no appreciable sonic attributes of its own? It's like trying to review a glass of distilled water for a wine magazine. There simply aren't that many synonyms for "transparent."
That's not the say that the K-300i is flavorless. It's simply that any spice comes from the music you feed it. With "Rock Steady," for example, from Aretha Franklin's 1972 album Young, Gifted and Black (Rhino Atlantic, downloaded from HDTracks in 96/24 ALAC), I was absolutely blown away by the bottom end, from the water-drop bass in the intro to the funky bassline that drives the song. More impressive, though, was the delineation of all track's densely mixed elements, from the stank-nasty rhythm guitar and washboard off on the left side of the soundstage to the higher-pitched percussion leaning hard toward the right. Through it all, though, Aretha's voice remained rock-solidly centered in the middle of the downright massive soundstage. The Krell K-300i presents it all, with no editorializing, no coloration.
I know I'll probably get booed right out of the comments section for admitting this, but one of my go-to tests for digital-to-analog conversion is to compare high-res and CD-quality versions of the same master and listen for appreciable differences. In my experience, the better the DAC, the fewer differences there are. And indeed, when I compared the 96/24 ALAC version of "Rock Steady" to a 44.1/16 file I converted myself, I honestly couldn't hear any appreciable disparity between them.
I also fed the K-300i my standard 192/24 and 96/24 "Warbles" tests, stolen unapologetically from Xiph.Org, to test for intermodulation distortion. Both "Warbles" tests did result in some audible artifacts, but very quiet ones. Quieter, in fact, that the softest parts of Lisbeth Scott's "Charmed," from her album of the same name (AIX Records, 96/24).
This track may not fit the traditional notions of "dynamic," but Scott's voice does go through ebbs and punctuated bursts of volume that the K-300i delivered with aplomb. What really stood out, though, was the purity of tone, especially with the piano accompaniment and Scott's falsetto vocals starting around the one-minute mark. I hate to use words like "sweetness," as that would connote some sort of tweaking in the upper frequencies, and no such is evident. But there's no denying that the integrated amp handles these delicate flourishes exactly as well as it does the punchy sizzle of Aretha's "Rock Steady."
After moving to an AV setup, I cued up the 4K HDR Vudu stream of Avengers: Infinity War to prep for the upcoming home video release of Endgame, and found the K-300i to be more than capable of keeping up with the film's dynamic action and dense sound mix, even with that mix limited to stereo. Of course, this integrated amp doesn't decode any form of Dolby (or DTS), so the audio was output from my Roku Stick+ in PCM, but that had no bearing on fidelity. All in all, I found the movie-watching experience wholly satisfying from a sonic standpoint.
It's been ages since I've watched the Blu-ray release of Cloud Atlas from front to back, mostly because I've been holding out hope for a UHD release with HDR. But no such seems to be on the horizon, so I settled down with the film again in boring old 1080p.
This is a disc that I often use for dialogue clarity torture tests, especially the futuristic scenes with Tom Hanks, like the one that opens the film. Even without the benefit of a dedicated center speaker (or maybe because of the lack thereof), I found those nigh-indecipherable lines to be delivered with utter clarity and discernibility.
Indeed, that was true of the entire film. From beginning to end, the K-300i passed the audio along with unimpeachable lucidity, utter bass authority, and delightful purity of tone for the underappreciated score. The title sequence in particular moved me in a way I don't quite remember being moved in the past by this same selection. The way the K-300i handled the delicate plucking of strings and the marching bassline of that piece left me so wanting for more than as soon as the end credits rolled, I cued up the score via Spotify Connect and let it play from beginning to end.
Having the Oppo connected to the K-300i also gave me the opportunity to spin my SACD of The Rolling Stones' Sticky Fingers, specifically "Can't You Hear Me Knocking," which isn't exactly an audiophile darling, but it does make for a great test of stereo imaging. But more than that, what I really came away impressed by was the Krell's ability to really unlock the sense of space captured in the recording--the subtleties of depth in the soundstage that often get obscured by lesser gear.
The same was true of "Spoonman" from Soundgarden's Superunknown (streamed via Qobuz in 192/24). Yes, the authority and clarity of the bass absolutely blew wind up my skirt, but more than that, what kept me coming back to this track time and time and time again (so much so that my American Staffordshire Terrier, Bruno, who is normally a constant presence in my lap, grumbled, got down, and stomped out of the room) was the way the K-300i delivered the swirling cacophony of clattering spoons that kick in around the 2:30 mark. Despite numerous play-throughs of the song, the only note I managed to scribble on my notepad was "holographic," and I'll withhold, out of pride, the number of exclamation marks that followed that singular observation.
It's also worth noting that, throughout my testing, the K-300i never got overly toasty. In fact, it's a lot cooler to the touch even after an afternoon of music listening than most new Marantz AVRs are after a few hours of casual TV-watching.
The biggest beef I have with the Krell K-300i is its remote. While the main body of the remote is hefty as heck and quite substantial feeling--what with its solid metal construction and grooved back panel--the metallic buttons don't feel quite so substantial. In fact, they feel a little flimsy.
But that's not the biggest problem. Worse by far is the un-ergonomic layout of the remote. The volume up and down buttons are centrally located, no larger than any of the rest of the buttons, and difficult to locate by feel alone, even if they are somewhat set apart by being on a row to themselves.
Navigating the setup menus is frankly more difficult than it should be via the remote. To access the menus, you logically press the MENU button, but that's where all logic ends. To navigate the menus, you press the volume up and down buttons and the balance left/right buttons above and to the left, not the nav buttons toward the bottom of the remote. To confirm choices, you press the ENTER button in the top portion of the remote, not the select button in between the four-way nav buttons mentioned above. In weeks of playing around with the K-300i, I simply never got used to this.
For what it's worth, those nav buttons, as well as the transport controls, cannot be used to control any music played through the K-300i. They're intended for use only with Krell CD/DVD players, which are no longer manufactured.
Simply put, I feel like a product that delivers so much on the performance level deserves a better remote than the one we're given here, although this is of course less of a concern if you're using the K-300i with an advanced home automation and control system.
My other concerns are pretty well documented above, but if you're the type to skip straight to the criticism, here's a brief recap: Although the K-300i is positioned as an AV device, not merely an audio one, its utility on the video side is somewhat limited by the fact that it doesn't decode Dolby or DTS audio, nor does it have any internal bass management. You'll need to use your subwoofer for that, although thankfully there are still plenty of subwoofers with internal crossover capabilities and speaker-level outputs.
The Krell K-300i also lacks any form of room correction. Even a basic parametric EQ would have been welcomed, as there are room modes to be overcome in my bedroom AV system that cannot be ameliorated by subwoofer positioning alone. My recommendation: if you're planning on using the K-300i in a 2.1 AV setup, make sure your subwoofer not only has speaker-level outputs and crossover capabilities, but also some form of auto room EQ or parametric EQ.
On a more personal, subjective note, I'm also a bit bummed that the K-300i features no headphone amp.
Comparison and Competition
As I said in the intro, video connectivity is starting to become more and more common in the two-channel world, and there are a handful of competitors that you might consider if you're in the market for something like the Krell K-300i.
Lyngdorf's TDAI-3400 comes to mind as one potential alternative pick. At $7,199 fully decked out with all its optional modules, it offers many of the features of the K-300i with its own Digital Module, including single-ended stereo analog inputs (five in this case), balanced XLR stereo inputs (only one), USB Type B, coaxial digital (two), optical digital (three), as well as similar control functionality. It adds an AES/EBU XLR digital input, and ups the HDMI inputs to three (2.0 with HDCP 2.2 and support for 4K/HDR). It also boasts similar network connectivity, support for a similar array of apps, and is Roon Ready, but as best I can tell it doesn't decode MQA itself.
In my estimation, given that I only have hands-on experience with the Krell, the two most significant differences between them are amp topology (the TDAI-2170 is fully digital) and EQ/filtering/bass management (the Lyngdorf features the company's advanced RoomPerfect room correction software and digital crossovers). The Lyngdorf also seems better supported by advanced control systems.
If your needs lean a little more heavily toward the video side of the equation, and you don't mind a much bulkier chassis, I might also suggest that you take a look at Arcam's SR250 Stereo AV Receiver ($3,600). The SR250 goes big on HDMI connectivity, with seven 4K/HDR-capable inputs (HDMI 2.0 with HDCP 2.2) and three outputs, although it follows the silly convention of other Arcam/AudioControl/Lexicon receivers built on this same platform of having an HDMI input labeled "VCR."
It lacks a USB-B input, and features no balanced inputs. It also lacks Roon support or MQA decoding, and its output is limited to 90 watts per channel. But the SR250 does boast Class G amplification (which I absolutely adore), and features Dirac Live room correction (ditto). In many ways, you can think of the SR250 as an updated, two-channel version of the Arcam AVR750 I reviewed a few years back.
If, on the other hand, you're way more of a streaming music aficionado, I think you would do well to check out the NAD M10 Masters Series ($2,750). This petite unit doesn't offer HDMI inputs except for its HDMI eARC port, so you would need to connect any additional video sources directly to your TV and use it for input switching. There's no fancy room correction here, but the M10 does feature a dedicated subwoofer output with bass management, and of course it supports BluOS, and all that goes along with that streaming platform, including support for all the major music streaming apps, as well as multiroom functionality. It decodes MQA, supports Siri via AirPlay 2, and comes out of the box with Amazon Alexa voice control integration.
Here at HomeTheaterReview.com, we primarily have two types of readers. On the one hand, we have the "sound quality is all that matters" crowd. On the other, we have those who sling poo at the screen if I don't obsess over ergonomics, features, and usability in my reviews.
If you fall into the latter group, what can I say? This probably isn't the product for you. The poorly designed remote, combined with some missing features that many may consider essential (headphone output, bass management, parametric EQ, possibly even room correction) probably put this one out of the running, despite its undeniably pure performance.
For those of you in the first group, I encourage you to locate your closest Krell showroom and audition the K-300i at your earliest convenience, assuming it fits your needs and budget. Of course, it needs to be said that I need to partition you lot into another two groups: those who are looking for a distinctive sonic signature, and those who want to get as close as possible to the impossible goal of "a straight wire with gain." If your tastes lean toward the latter, the K-300i probably comes as close as I've ever heard from an integrated amp.
• Visit the Krell website for more product information.
•Can Krell Make a Comeback When Other Legendary AV Brands Could Not? at HomeTheaterReview.com.
• Krell Solo 375 Mono-Block Amplifier Reviewed at HomeTheaterReview.com.