Datasat RS20i Surround Sound Processor Review
Datasat put the 'cinema' in home cinema.
IntroductionWhilst you might not have heard of Datasat before, you will undoubtedly be familiar with DTS (Digital Theatre Systems) from trips to the cinema, not to mention on DVDs, CDs and Blu-rays. Datasat is a British company that specialises in secure communication and in 2008 they bought the cinema division of DTS to create Datasat Digital Sound. The next time you're at the cinema, take a look at a poster or watch the end credits of a movie and you'll see the Datasat logo. What, you may ask, does a company that delivers professional audio in the cinema have to do with the consumer market? Well, Datasat were constantly receiving enquiries from individuals looking to buy their commercial processor - the AP20 - for their home cinemas. So, using the AP20 as their starting point, Datasat decided to create an audiophile-grade, no compromise surround processor that would truly put the 'cinema' into home cinema.
No expense was spared in developing this new product and the result was the RS20i, the most versatile, customisable and feature-rich audio processor currently available in the high-end consumer space. The RS20i uses Datasat's professional cinema processor as the starting point and then packages it in an elegant chassis designed by the Neal Feay Company. Datasat then added Dolby processing, a feature that's missing from the AP20 for obvious reasons, as well as memory profile settings, stackable multiple EQs, Dirac Live's remarkable room optimisation software and extensive automation controls. The RS20i currently includes four HDMI inputs and one HDMI output, along with up to 16 channels of digital or analogue output, but its modular design allows for easy expansion or upgrade and there's a USB port on the front for firmware updates. The result of Datasat's efforts is a product that could potentially be the Holy Grail for AV enthusiasts - one that truly delivers cinema sound in the home. Let's see if the RS20i lives up to both that promise and its illustrious heritage.
Design and ConnectivityThe RS20i has a gorgeous chassis that exudes a minimalist appeal whilst retaining a well machined and engineered construction. This is the kind of solid and robust build quality that only comes from years of experience in the professional arena. The thick metal facia has a control dial on the right and a logo panel on the left, which doubles as the on/off button, and behind this panel is a USB port for firmware updates. The USB port can also be used for storing and retrieving any memory presets and operational profiles. There is a large central touch pad display, where all the RS20i's controls and menus can be accessed, although once connected to a network the processor can also be controlled via a laptop, iPad or smartphone, with the front panel replicated on the device.
At the sides of the RS20i there are grilles for the cooling fans and it's here that we should point out the processor's only real weakness - it's noisy. Of course the chances are that the RS20i will be part of a professional installation and, as such, will be in a separate equipment room but if you're thinking of using it near your seating position, you need to be aware of the fan noise. The RS20i uses eight Analog Devices 400MHz DSPs and Burr-Brown PCM4104 DACs, supporting up to 85 digital and analog inputs as well as 34 audio outputs. This number of outputs allows the RS20i to accommodate all surround sound formats currently available – including true 3D sound. In addition, three expansion slots at the rear allow for the easy addition of extra channels and features in the future.
Also at the rear is a set of connections that reflect Datasat's audiophile ambitions and their professional pedigree, with inputs for no less than 8 analogue and 16 digital channels and outputs for up to 16 channels of digital and analogue audio. To save space the RS20i uses balanced DB25 connectors but there are also digital inputs ( two optical and one coaxial) and two pairs of analogue stereo inputs with RCA connectors. There are four HDMI inputs and one HDMI output - all version 1.4a - which allows the RS20i to pass video, including 3D, completely untouched. The RS20i is clearly aimed at the professional installer and as such it includes RS232 connectors for serial control and servicing, 12v triggers, an Ethernet port and a bi-directional GPIO (general purpose input/output) connection. There is also an XLR connector for a calibrated microphone when performing a basic setup using the integrated RTA, a Monitor Out and Hearing Impaired Audio Out, both using RCA connectors. Finally there is a three pronged connector for the power cable, an access panel for the fuse and a power switch.
Setup and MenusDespite its complexity and versatility, the RS20i is surprisingly intuitive to use and once you've spent some time familairising yourself with the various menus, it all starts to make perfect sense. Obviously the majority of people buying the RS20i will leave the setup to a custom installer but if you're a tweaker then you'll be in heaven. You can access all the controls and menus from the front touch panel but you can also replicate them on a connected laptop, iPad or smartphone. You can also create your own screen saver using an image that matches the 640 x 480 resolution of the front panel.
When you turn on the RS20i, the first thing you see is the Home page; here you can choose between the user-assigned audio inputs and see the user-assigned channel names, along with any EQ settings, Output selections, Sources and whether Dirac has been activated. It also shows you volume bars for all the output channels associated with the current audio input and watching the bars going up and down can be interesting, informative and slightly addictive. The volume is controlled using the front dial and there is a mute button, along with a separate monitor control for any connected external powered speaker. You can also access any manual automation controls that have been created and enter the Setup menu.
The Setup menu allows you to then access System Info, Access Control, save and restore presets from a connected USB stick and run any software updates. You can also access the Automation and Network sub-menus, along with the Inputs sub-menu. Here you can select the source, depending on what's connected, and set the Channel Names. Although in the case of HDMI, the first eight channels are already set by the HDMI standard itself. It's worth pointing out that the RS20i has full EDID over HDMI, allowing the processor to give you all the available information about a connected device.
So far, so pretty standard, but where the RS20i starts to move into a field of its own is in terms of the flexibility with the input/output routing and the crossovers. There is a matrix that allows you to map any of the 16 input channels with any of the 16 output channels, although again if you are using HDMI, the first 8 input channels are fixed. However you can map any of those eight channels to any of the sixteen output channels, which was handy with the RA7300 power amplifier we were using because it only identified the speaker terminals using the letters A to G. For the Hearing Impaired output channel, the first three input channels (L,R, and C) are mixed in a ratio of 50% Center channel, 25% Left and 25% Right channels. It is here than you can set the low and high pass filters for each individual output channel. Once assigned, you then move on to the Channel Delays page where you can set the delay in milliseconds for all 16 input and output channels.
After assigning the inputs and outputs, mapping them, naming them, setting any low or high pass filters and setting any delay, you can move on to setting the audio levels using a sound pressure level meter with the microphone at the sweet spot. It is important to perform the basic setup before running the Dirac Live room optimisation software. The RS20i has a highly sophisticated bass management system that allows for a genuinely impressive level of customisation. After selecting the appropriate speaker configuration you can - along with the selecting the low and high pass filters for each individual speaker - also assign the frequency crossover for each speaker. The RS20i officially supports up to four subwoofers but if you only have 7 main channels and run the subs routed in mono then, in theory, you could run as many as 9 subs using individual delays. The result is a degree of bass management that is almost unheard of in a consumer product - as we said, it's a tweaker's dream.
Dirac Live Room OptimisationThe RS20i comes with 31 bands of third octave and three user-adjustable bands of parametric equalization on every channel. The Parametric EQ is an optional adjustment and is in addition to 1/3 Octave EQ. It is only available with low frequencies and offers more control than 1/3 Octave EQ. The Parametric EQ screen looks similar to the 1/3 Octave EQ screen but displays a frequency range from 20 to 200Hz only. The RS20i can also use Dirac Live room optimisation software, which isn't included with the processor and although you can buy Dirac Live separately, it costs around £2,000. However your dealer should perform a full Dirac Live calibration during the installation, as part of the overall cost of the RS20i. Dirac is calibrated via an Earthworks microphone attached to a laptop via a USBpre2 sound card. The laptop sends PN calibration tones and commands to the RS20i via IP and, given the number of calculations that are required, it is best to use a suitably powerful one. As is always the case with room optimisation software, the more measurements you take, the more accurately the software can map the environment. The ideal number of measurements is around nine, taken at varying heights and positions around the sweet spot.
The RS20i is the only home cinema audio solution to feature Dirac Live room optimisation technology. This software is the result of years of research into digital sound optimisation and room correction. Rooms, amplifiers and loudspeakers inevitably distort the sound both in the frequency domain and in the time domain. By digitally optimising the audio signal prior to sending the signal to the amplifiers and by measuring the output from each speaker of the audio system such that it is perfectly adjusted to the acoustical behavior of the listening environment, a much more transparent and true-to-the-source sound can be delivered. Dirac Live is a state-of-the-art digital room correction technology which optimises the sound both in terms of the impulse response as well as the stationary frequency response. The result should be a substantially improved musical staging, clarity, voice intelligibility, and a deeper and tighter bass, not just in a small sweet spot but in the entire listening environment.
By digitally optimising the output from each speaker of the audio system such that it is adjusted to the acoustical behaviour of the listening environment, voice intelligibility is improved and music becomes clearer. Acoustic room modes distort the character of the bass and loudspeakers continue to ring even after a bass punch has been delivered due to mechanical restrictions. Dirac Live effectively prepares the loudspeaker for the sound that is coming and reduces the settling time of the loudspeaker, thereby achieving a tighter, deeper and more defined low end. Dirac Live also restores the sound stage so that the localisation of sound events become much more detailed. Time-domain distortions, caused by diffraction, cross-overs, and early reflections, make it difficult for our brains to interpret the sound. A smooth frequency response and an aligned phase response make the sound more natural and prevent listening fatigue during prolonged listening sessions. The phase response correction and magnitude response optimisation of Dirac Live, is designed to reduce fatigue and make listening more pleasurable.
Dirac Live provides impulse response correction over larger listening areas, which is critical for multichannel and stereo perception. Localization and stereo listening, in general, depend on the similarity between and the quality of the channel impulse responses. Dirac Live improves the precision and the clarity of the audio imaging using proprietary technology that takes the stationary frequency response correction and looks at the variations between different measurement positions and carefully makes a correction based on spatial variations. Dirac’s mixed-phase filter technology also helps because loudspeakers measured in rooms are mixed-phase and consequently only a mixed-phase correction can restore the intended impulse response.
Audio PerformanceSo once the RS20i had been installed, setup and calibrated using the Dirac Live room optimisation software, we got down to the important part - the actual performance. We used the processor in conjunction with Datasat's own RA7300 7-channel power amplifier, along with B&W speakers and SVS subwoofers. The result was the best audio experience we have ever had at home, with the combination of the RS20i, the Dirac Live software and the RA7300 amplifier delivering a truly immersive experience. The audio on movie soundtracks wasn't just heard, it was felt and experienced in a genuinely visceral way. The RS20i's flexibility in terms of setup meant that every aspect of the system was performing at its very best. The Dirac Live software equalised any characteristics inherent in the speakers or the room itself, causing them to melt away leaving a suitably transparent delivery. The slight dip in the mid-range of the B&Ws, which gives them their distinctive sound was eliminated and a wicked room mode at around 50Hz was also dealt with in ruthkess fashion.
The result of this acoustic transparency was that there were no distractions and the sound designer's art was allowed to shine through. The room optimisation was only part of the story, of course, but there is no doubt that the equalisation resulted in all the speakers perfectly matching each other tonally. We were actually quite impressed at how similar all four surround speakers were when measured but the software easily fine tuned any minor differences in their responses. The audio performance was totally engrossing, with the RS20i perfectly steering sound effects and utilising the power of the RA7300 to its full extent. The result was a truly remarkable combination of detail, control and dynamic range, which made the overall sound totally immersive. Musical scores had a wonderfully expansive front soundstage, whilst dialogue remained perfectly clear and effects precisely localised, with seamless pans around the soundfield. The bass management was exceptional and when the low frequency effects kicked in, the impact was almost overwhelming at times.
Since it was the first DTS cinema release, it seemed appropriate to start with our Blu-ray of Jurassic Park and the RS20i didn't disappoint. The T-Rex attack was as powerful as ever but the refined bass management made for a true sonic assault. From the rain hitting the car windows to the initial bass thuds that accompany the ripples in the glass of water to the full-on roar of the T-Rex itself, the RS20i was a masterclass in control and precision. All the sounds, from the music to the dialogue to the effects were perfectly rendered and the entire scene benefited from the soundfield filling the room. The processor took full advantage of the power on offer from the RA7300, resulting in a breathtaking level of dynamic range. This effective use of dynamic range was perfectly demonstrated in the soundtrack to Oblivion, which is in itself a superb piece of acoustic design. This was superbly replicated by the RS20i, from the tiniest flicker of a candle over a quiet dinner scene to the utter sonic bombardment of a nuclear explosion, the processor didn't put a foot wrong.
It was this ability to combine detail, control, bass and dynamic range that makes the RS20i so impressive and film after film the processor showed that it could deliver the goods in spades. We tried different audio codecs, including DTS-HD Master Audio, Dolby TrueHD and LPCM, along with 2-channel, 5-channel and 7-channel mixes, and the processor handled them all with ease. The bass driven soundtrack to Danny Boyle's Trance was beautifully recreated thanks to the tight and wonderfully integrated low end. The recurring motive of one of the characters tapping on a pane of glass was effectively rendered, it's impact gradually increasing as the film progressed. However it wasn't all bombast and the Datasat could be subtle as well, as we found with Nick and Nora's Infinite Playlist. Here the RS20i delivered this dialogue heavy comedy with skill, capturing the atmospheric sound effects of New York at night, whilst also superbly reproducing the film's extensive use of music superbly. The simple fact is that whatever your taste in films, the RS20i will deliver the soundtrack exactly as the creators intended, and make it hugely enjoyable at the same time. Home cinema indeed.
- Reference audio performance
- State-of-the-art room correction
- Superb bass management
- Staggering level of flexibility
- Professional build quality
- Superior connections
- Fan noise
- It ain't cheap
Datasat RS20i Surround Sound Processor Review
The short answer is yes it does, and then some, but we figure you'll want a more detailed conclusion than that, so we'll go through what it is that makes the RS20i so good. It's worth pointing out that the RS20i is so flexible and has so many features that even in a detailed AVForums review we can only scratch the surface of its full capabilities but we'll cover all the main points. Let's kick-off with the outward design and here the RS20i immediately scores with a gorgeous but minimalist chassis that still manages to incorporate the kind of solid and robust construction that only comes from years of experience in the professional arena. The thick metal facia has a control dial on the right and a logo panel on the left, which doubles as the on/off button, and behind this panel is a USB port for firmware updates. There is a large central touch pad display, where all the RS20i's controls and menus can be accessed, although once connected to a network the processor can easily be controlled via a laptop, iPad or smartphone.
At the sides of the RS20i there are grilles for the cooling fans and it's here that we should point out the processor's only real weakness - it's noisy. Of course the chances are that the RS20i will be part of a professional installation and, as such, will be in a separate equipment room but if you're thinking of using it near your seating position, you need to be aware of the fan noise. Moving to the rear of the RS20i we find a set of connections that reflect Datasat's audiophile ambitions and their professional pedigree, with inputs for no less than 8 analogue and 16 digital channels and outputs for up to 16 channels of digital and analogue audio. To save space, the RS20i uses balanced DB25 connectors but there are also optical and coaxial digital inputs and analogue stereo inputs with RCA connectors. There are four HDMI inputs and one HDMI output - all version 1.4a - which allows the RS20i to pass video, including 3D, completely untouched. The RS20i is clearly aimed at the professional installer and as such it includes RS232 connectors for serial control and servicing, 12v triggers, an Ethernet port and a bi-directional GPIO (general purpose input/output) connection. There is also an XLR connector for a calibrated microphone when performing the Dirac Live room optimisation and three expansion slots for future developments.
Despite its complexity and versatility, the RS20i is surprisingly intuitive to use and once you've spent some time familairising yourself with the various menus, it all starts to make perfect sense. Obviously the majority of people buying the RS20i will leave the setup to a custom installer but if you're a tweaker then you'll be in heaven. The RS20i comes with 31 bands of third octave and three user-adjustable bands of parametric equalisation on every channel. In addition, each channel includes low, high and band pass filters, as well as advanced bass management features including full and user-adjustable bass control on each individual front and surround speaker. The RS20i supports up to four subwoofers, enabling enhanced surround settings such as 11.1, 12.2 or 12.4 and it's the only consumer product to feature Dirac Live room optimization technology. This delivers the most advanced impulse and response correction available to deliver a natural and immersive listening experience. The essential elements of your setup can be quickly and easily saved with up to 20 user-defined set-up and operational profiles and these memory presets can be easily transferred to a USB stick for safe storage and retrieval.
We reviewed the RS20i with Datasat's own RA7300 7-channel power amplifier, along with B&W speakers and SVS subwoofers, and the results were nothing short of spectacular. Thanks to the flexible setup and Dirac Live software, the entire system performed optimally and the presence of the room itself simply disappeared. The impulse and response characteristics of the speakers were perfectly equalised and the bass was seamlessly integrated, delivering the most visceral and enjoyable surround sound experience we have ever had at home. The audio was totally engrossing, with the RS20i perfectly positioning sound effects and utilising the power of the RA7300 to its full extent. The result was a truly remarkable combination of detail, control and dynamic range, from the flicker of a candle to the blast of a nuclear explosion, which made the sound totally immersive. Musical scores had a wonderfully expansive front soundstage, whilst sounds still remained precisely localised and panned seamlessly around the soundfield. The bass management was exceptional and when the low frequency effects kicked in, the impact was almost overwhelming. Ultimately we had no doubt that our audio experience at home was equal to, if not better, than anything we were likely to have at the typical cinema and you can't ask for more than that.
The Datasat RS20i audio processor certainly isn't cheap but then the best rarely is and, for once, a product actually achieves what it set out to do - deliver uncompromised cinema sound in the home. The RS20i sets the benchmark by which all other domestic audio processors will be judged and as such there can be only one conclusion - Reference Status!
Suggested retail price when reviewed: £18,600.00
Value For Money9
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