DALI CALLISTO 2C active speakers / Soundhub wireless streaming controller
+ Detailed, expansive sound stage, with very fine treble textures and shading from the integrated super tweeter; good rhythm, pace and timing – nimble yet full upper bass; very flexible digital and analogue inputs on the Soundhub, especially with BluOS module which turns it into a full-fledged network streaming solution; good convenience features such as auto sensing for inputs, and a visible volume indicator; MQA support via the BluOS module adds the ability to stream high res from TIDAL; nicely crafted RF remote which does not require line of sight to work.
– No DSD support, no asynchronous USB digital input, no adjustment of the speaker output to suit your room; KEF LS50 Wireless also a formidable pair of active speakers – may suit your room better.
DALI has been a reliable purveyor of sensible speakers, from budget to the high end, but has always stuck to its knitting with passive designs and a house sound, winning plaudits at each price point for being well-engineered, well-built and nicely-finished. But there has been a move towards active speakers in the last few years – a concept which music professionals have adopted already for many years.
In the consumer space, more home-friendly designs have come to the fore, from the quasi-active speakers at the lower end to the mid-range designs from ELAC and KEF, to name but a few. And at the other end, Kii Audio’s Three active speakers truly deliver high-end performance.
Many of these have integrated streaming into their design, making them complete solutions with the addition of a smartphone or tablet, and an Internet connection. Thus, active speakers have the potential to deliver a fully-integrated system with minimal box count.
With the launch of the Callisto range in 2018, Dali took a step into a bold new future with active speakers, and has done so in a very convincing way. Not content to simply add some amplification to warmed-over passive designs, Dali has dug deep into its engineering capabilities to come up with all-new designs which incorporate a number of innovations and some curious choices.
The Callisto 2Cs are a handsome pair of bookshelves with three drivers a side. A 6.5-inch bass driver takes on the bass and mid duties from 47Hz up; interestingly, there are two tweeters – a 29mm soft-dome tweeter taking things from 2kHz up to 15kHz, and a ribbon super tweeter from 14kHz to 32kHz, making it a very wide-band design out of the box.
Behind these drivers are a pair of Class D amps per side – one for bass duties and the other for treble duties driving both tweeters through a simple analogue crossover. The crossover between the treble and mid/bass is executed in DSP before the Class D amps which are good for 250W apiece, making this a true active design, albeit with a simple passive crossover to mate the two tweeters. The rationale for the two tweeters is not only to extend the response above 20kHz, but also to provide a smoother dispersion of high-frequency information and hence, superior imaging and a larger sweet spot.
On the back of each of the speakers are a USB port for service, a single phono input which you can connect to an analogue output preamp, a simple display to show where the speaker is oriented with respect with the listener and a pairing button. There is also a power switch with a two-prong non-grounded IEC mains inlet, along with a bass reflex port, the last suggesting that these speakers should not be sited too close to a back wall or on actual bookshelves.
The finish on the white review pair was good, but not as “high end” as one might expect from the price. On the front are a pair of smart-looking grilles which use a combination of pegs and magnets to snap into place.
Of greater interest is the Soundhub, which is the raison d’etre for this system. It utilises a proprietary wireless protocol which streams a 24-bit/96kHz I2S (Inter IC Sound) signal to each speaker. The Soundhub has a lot of built-in connectivity – digital inputs include co-axial and Toslink. The only missing digital input is an asynchronous USB one. There are also two analogue stereo inputs – one pair of phono inputs and one 3.5mm TRS mini-jack input.
In addition, there is a Bluetooth streaming input and two expansion ports. There are also two outputs – one stereo pair of phonos and a mono subwoofer out which sends out bass information from 100Hz down.
The review unit came with a BluOS card in the first expansion port, which makes the Soundhub a full-fledged network streaming unit. On the back of the BluOS unit are a RJ-45 network jack, a Wi-Fi dongle in a USB port and a second USB port to connect a USB disk with music files on it. On the rear, there is a pairing button, and on top, a display to show the speakers connected to the Soundhub. Curiously, there is space for additional speakers on the display, suggesting that there might be a home theatre module with HDMI inputs in the works.
There is also a very nicely designed RF remote control which is made of metal and has a nice heft on it. Simple controls for volume are on the remote, as well as mute and source switching. Volume can be adjusted on the remote, with the knob on the Soundhub itself and also interestingly, using swipe control on the upper front edge of the speakers.
There are no other controls for the speakers themselves unlike the KEF LS50 Wireless – the only app available is the BluOS app which interfaces with the BluOS module.
I listened to the 2C and Soundhub combination principally through the included BluOS module, which integrated easily into my existing BluOS and Roon set-ups. In addition, I also connected my Denon DP80 turntable via an EAR 834P phono stage into the analogue phono inputs.
I also tested Bluetooth streaming from an Astell & Kern Kann, which can connect using the apt-X HD protocol (nominally a 24/48 signal). In addition, I also connected my own Chord Hugo 2 DAC via single-ended phono connections directly to test the speakers without the Soundhub.
I set up the Callisto 2Cs on a pair of steel 24-inch four-pillar stands with a pair of ISOAcoustics Isolators under each, about 2.5m apart and about three metres from the main listening position, toed-in a little to face almost square to the listening position. Walls were more than three feet away from the rear and the sides of the speakers. I took the grilles off for most of the listening.
As with my previous reviews, I kicked off the proceedings with analogue playback from the Denon DP80, starting with a few known favourites such as the Great Jazz Trio’s live recording at the Village Vanguard (East Wind EW 8053), where the dimensionality of the soundstage was evident, with good width, height and depth from the cues in the recording. Tony Williams’ drums were superbly reproduced, the super tweeter adding a touch more refinement to the cymbal textures.
Moving on to some pop, on a Japanese 45rpm 12-inch pressing of Frankie Goes to Hollywood’s Relax, the 2Cs showed good pace, rhythm and timing, taking on the 1980s production and “hot” cut in its stride. Bass was ample with a hint of warmth in the upper registers, certainly more than enough for most people, unless your tastes run to very bass heavy music which demands a much bigger low end.
I also hooked up my resident Sony HAP-Z1ES hard disk player to the analogue inputs of the Soundhub, and first played Radka Toneff’s Fairytales (Single DSD rip from SACD). Her vocals were palpable, imaged solidly in the centre of of the two speakers. Switching to Red Book material, on Tsuyoshi Yamamoto’s Blues for Tee (TBM CD 2541 – FLAC rip 16/44.1), the speakers again took on the rhythm and pacing well, with the double bass and drum combination set well with the leader’s percussive piano style in a live setting.
It is evident that the analogue input is not an afterthought – the analogue-to-digital conversion is done well and is transparent to the source. I could discern the difference between the different sources and even detect the “house sound” from the HAP-Z1ES, even through an analogue-to-digital-to-analogue chain.
I now switched to the BluOS module to stream digital files from my resident Bluesound Vault as well from my Roon Server (BluOS components are also Roon Ready devices). This was the most convenient way to listen to a variety of music. Via BluOS, the Soundhub is able to access almost all music streaming services – Spotify Connect is onboard, whilst TIDAL, Qobuz, Deezer, Murfie etc. are available via the BluOS app on your phone or tablet. In addition, the module allows you to stream from any NAS or from a hard disk plugged into the USB slot in the back. Note that the BluOS module is able to stream up to 24/192 PCM, DSD is not supported. Via Roon, the endpoint is set up correctly and DSD music is transcoded to PCM on the fly as needed.
I started out with the same files as from the Sony player to see if there was a difference in presentation. Although the speakers’ qualities are evident, there was a notable difference given the different input chain. Streaming via the BluOS module showed a different voicing than from the Sony, which can be a little polite in nature. The BluOS module was a bit bigger and bolder, if not quite as open in the midrange than than the Sony via the analogue inputs.
Continuing the listening, I switched to Roon to stream MQA tracks from TIDAL – the Callistos with the Soundhub are MQA certified. I started again with Blue Maqams by the master of the Oud, Anouar Brahem (ECM 2580). The MQA stream was rendered with great delicacy, with his plucking mirrored by Dave Holland’s double bass in the opening track. Then, with the layering of Jack DeJohnette’s ride cymbals floating above both, the sense of height was impressive. I suspect the super tweeter’s dispersion and extension contribute to that effect.
Switching genres, streaming Marianne Thorsen’s Mozart Violin Concertos released by 2L on MQA on TIDAL, the 2Cs put on a great show of the string textures, and imaging was superb (though I felt that my resident KEF LS50 Wireless pulled out a smidgen more detail and imaged a bit tighter, but with less scale).
I also tested Spotify Connect to the Soundhub, which was very pleasant listening. The 320kbps Ogg-Vorbis streams do show some loss of air and presence, but these are largely sins of omission. This makes for a very pleasant way to browse your Spotify connection.
To test the line level phono inputs on the back of the speakers, I pressed into action a Chord Hugo2 DAC/headphone amp driven from a Sonore Microrendu. Bypassing the Soundhub yielded an interesting result – there is a small gain in transparency, but not so much as to negate the convenience of the Soundhub. Again, the speakers show the ability to project the character of the Hugo2 – the crystalline clarity of the midrange was evident as was the dynamism.
I rounded off the testing by streaming via Bluetooth Apt-X HD from the Astell & Kern Kann. As might be expected, there is a loss in transparency, but this was quite slight in most cases and for casual listening would not be an issue at all.
THE LAST WORD
Dali has done a great job on its first foray into the active arena, with a pair of speakers which can integrate well into existing systems as well as being a complete audio solution in their own right.
But I was forced to think hard as to whom this offering is targeted at – the stereotypical audiophile? Or a lifestyle-oriented user? Or someone in between? It’s hard to see how a stereotypical audiophile would want the Dali 2Cs – although they are truly audiophile in quality, the close integration of the Soundhub and the active speakers make them less than appealing to those who relish the endless games of swapping out components.
On the other hand, these speakers are probably over-engineered for a lifestyle user – there exist a number of more home-friendly audio solutions which would probably suffice for non-critical listeners.
So this begs the question – is there a market of users somewhere in between? A user who appreciates a finer sound but also would like ease of use and the ability to integrate the speakers into a domestic environment? I am sure these people exist, but I am not sure how one would identify and market to such potential customers.
Compared to the KEF LS50 Wireless, which are also a formidable pair of active streaming speakers, the Callisto 2Cs outperform them convincingly in most aspects, most notably the scale and dimensionality of the soundstage, though they were not necessarily as detailed as the KEFs. The Dalis also win on a number of usability aspects such as auto-sensing inputs, visible volume indication and fewer wired connections required to each speaker. The KEFs do have an ability to tweak bass and treble levels, and sub crossover and level to suit different rooms and situations. As with all things hi-fi, your mileage may vary, so it’s essential to test both in your listening room.
Recommended with only one reservation: not because of shortcomings of the speaker themselves but rather the suitability of this complete system for the buyer. This could well be the only system you need if you don’t have the need to swap out/mix/match components.
Also note that the 2Cs have a bigger brother – the 6Cs which are floorstanding version with an additional bass driver, allowing for a deeper bass response. If your budget extends to that price point and room requires a bigger sound, those should definitely also be on your audition list.
Sources: Roon server to BluOS streaming card in the Soundhub, Astell & Kern Kann via Apt-X HD, Denon DP80 turntable/Micro Seiki MA505X arm/Audio-Technica VM 540ML MM cartridge, EAR 834P phono amp, Chord Hugo2 DAC driven by Sonore Microrendu in Roon Ready mode.
Price: €2,798 (speakers) / €649 (Soundhub) / 499 (BluOS npm)
Malaysian price: RM13,000 / RM3,020 / RM2,320)
Review units courtesy of Dali A/S (+603-7710 0202) / Find your distributor.