In hi-fi circles, Linn Products needs no introduction – it was the company that revolutionised high-fidelity system-building priorities in the 1970s with its first product, the Linn Sondek LP12 turntable. (See all audio reviews.) Until Linn started promoting the turntable as the most important component in the system – with vested interest of course since that was all it made at the time – it was commonly believed that the loudspeakers deserved the most investment. The amplifier was the second priority, with the turntable chassis distantly down the list. But founder Ivor Tiefenbrun evangelised his source component, with the pithy maxim ‘garbage in, garbage out’. In other words, if you don’t nurture the original musical signal from the record before it’s passed to the amp and speakers, you’ll only be reproducing rubbish. The company has expanded far beyond its early days of mechanical engineering, becoming a one-stop shop for complete hi-fi systems by investing its R&D and manufacturing capability in electronics – first analogue electronics to produce amplifiers; later and controversially by turning its methodical talents to digital audio. (When CD first appeared in the early ’80s, Linn Products ran marketing campaigns that compared the format to a lemon.) After diversifying into multi-room and home cinema in the ’90s the company today is again focused primarily on high-end stereo systems. Its complete systems can be configured with full-range speakers and multiple boxes of amplification easily totalling £20,000 and more. But down at the entry level a one-box music system like the Sneaky DSM can be found for under £2000. (See all digital home reviews.)
Linn Sneaky DSM review: Sneaky does it
The Linn Products Sneaky DSM is an audio streamer designed for connection to an ethernet network, with its own built-in stereo amplifiers. All you need to add is a pair of loudspeakers, and an iPhone or iPad to control it. You can also take more complete control with software applications available for OS X and Windows. From the outside, the Sneaky DSM is a no-frills metal-cased box that can be placed on a shelf, even hidden behind it, or fully installed behind a ceiling tile, for example. There are no user controls on the unit besides an on/off rocker. This DSM version of the Sneaky includes additional inputs – one stereo RCA phono, one each Toslink and coaxial S/PDIF, plus a trio of HDMI for integrating with TVs and set-top boxes. Linn also makes a single-source version without the added inputs for local sources, designated Sneaky DS. Conspicuous by absence is any digital audio output, save that found muxed within the HDMI output. Which is a shame – we were hoping to try the Linn network player connected to different amplifiers to better gauge its capability. Besides playing digital audio files from your NAS or computer server, there is internet radio capability. Three unique high-bitrate stations from Linn Records are already on the default favourites list, along with national BBC radio stations and a few commercial broadcasts. Adding more radio stations requires signing up to TuneIn Radio. You will need the desktop Mac OS X app to configure certain parts of the system, such as arranging which input sources are visible on mobile apps, but subsequently all operations can be controlled from an iDevice using the Linn Kinsky iOS app. (See also: How to make and receive HD phone calls: everything you need to know about HD Voice.)
Linn Sneaky DSM review: Kinsky kontrol
The Kinsky app interface is one of the best we’ve found for running a music system, with easy access to network music files, radio stations and additional sources alike. On the iPhone the more limited screen space means you need to slide left and right between three different screens to access all the functions: leftmost lets you choose your music source; centre screen gives the main transport controls and an illustrated list of tracks in your running playlist; and rightmost lets you navigate the directories of your music server. A neat trick we’ve not seen before is the means of selection of music as you surf around. A tappable button at the screen bottom lets you cycle between Play Now, Play Next or Play Later. Thus you can flit between tracks like a real-time jukebox using Play Now for one-off listening – or select Play Later/Play Next to add any given track to the playlist queue for later. To play a complete album, a more typical need perhaps, you actually need to go back one level to the full album listing; then press and hold on the album folder name to add this to the playlist. On the larger iPad only one is screen provided and in fact required. Here the interface is split down the middle, with server tracks ranged down the left and playlist or sources on the right. While the Kinsky apps worked fine to let us find music on our Synology NAS drive using an iPhone 5s and iPad 3, Kinsky resolutely refused to show the available directories when we tried an iPad Air and an iPhone 4S. Yet Kinsky could work on any of the above devices when using a QNAP NAS. We really don’t know who’s at fault here, and Linn told us it’s not encountered this problem before. With no real knobs or buttons on the Sneaky, you’ll also need to turn to the mobile app to set all-important volume. Tapping the small circular volume symbol (with handy numerical 0-100 level detailed inside) brings up a larger interactive round virtual volume dial, which you can gaily spin with your finger. It’s an intuitive solution that works well. Update: too late to try with the Linn Sneaky DSM, but we’ve been informed that the Kinsky app is to be replaced by a new iOS app named Kazoo.
Linn Sneaky DSM review: Technology
The Sneaky DSM is listed as able to field the usual alphabet soup of audio formats, namely FLAC, WAV, Apple Lossless (ALAC), MP3, WMA (except lossless), AIFF, AAC and OGG audio formats. It decodes digital audio with a 24/192-capable D-A convertor chip, and can play high-resolution PCM audio up to 24-bit and 192 kHz sample frequency. The Sneaky will not play the Scottish company’s once-favoured format of DSD, as found on SACD. There’s no Wi-Fi wireless option, perhaps wisely given that high-resolution audio demands a flake-free and timely datastream. All network data arrives at the Sneaky through an ethernet port on the back panel alongside the collection of audio I/O connectors.
Linn Sneaky DSM review: Class of D
Surprisingly, Linn Products has equipped the Sneaky DSM with a Class D amplifier in place of the usual hi-fi Class AB linear design. Linn has previously gone on record saying that Class D amps lack subtlety and suffer performance issues. So the Class D architecture remains an unusual choice in respectable high-quality audio equipment. It does have manifold benefits of cool running, low cost, and high power output with minimal power consumption, yet Class D still suffers from sub-high-fidelity sound quality. This may be apparent as grainy, distorted high frequencies and thinned, emotionless midrange. Some listeners complain of a mechanical lifeless sound, which may be a result of the technology’s amusical distortion products. Additionally Class D designs present challenges in suppressing RF emission, as the radio-frequency switching speed can cause EM radiation that pollutes other audio products. We have no doubt that Linn’s products pass every EMC requirement around the world, but in the world of audio our ears are more sensitive to radio-frequency induced hash than is required to meet safety limits set by international standards. Linn Product’s application here is a little different to the low-fi Class D found in most consumer electronics. It appears to be a ground-up design using discrete power MOSFET transistors; most cheap Class D amps in televisions, Bluetooth wireless speakers and similar low-grade audio products use a proprietary single-chip solution. As testimony to the efficiency and low-cost of executing Class D amplification, Linn has included not two but four complete amplifiers, enabling you to bi-amp a stereo pair of speakers. You’ll need use a special speaker set terminated with the four-pin Neutrik Speakon connectors.
Linn Sneaky DSM review: Sound quality
For a digital music streamer with a switching amplfier the Sneaky DSM could have a remarkably tidy sound. As we might expect from the technology, the bass was extremely well controlled. We heard this in lightning thumps of kick drums and the percussive slam from struck instruments. It gave the whole sound a sense of real control and well-metered timing. Tonally the Sneaky DSM kept a decent balance at most volume settings, with none of the euphonic bloom of some linear amplifiers that initially impress as warm-sounding by letting bass transients linger longer than they ought. Midrange and treble were somewhat dry yet managed to retain the colour of music for part of the time. By the standards of similar amp technology, we were impressed by the reasonably authentic timbre of brass instruments and acoustic guitars, for instance. Vocal lines were heard clearly enough, but not always cleanly. We noticed a trace of huskiness on most voices, as if the singer was working past a sore throat. Move to passionate female vocals like Janis Joplin singing ‘Me And Bobby McGee’ (24/96 FLAC), and the effect was altogether too close to the proverbial gargled glass to enjoy. Robert Plant suffered a similar fate in recent high-resolution reissues of the first three Led Zeppelin albums. We were startled out of our seat by the sheer dynamism the Linn unit could wring from ‘Good Times Bad Times’ (24/96 FLAC) for example, but the mash of splashy cymbals and strident vocal lines later detracted from the otherwise profoundly dynamic experience. Stereo soundstaging was found wanting. Image position was reasonably secure but front-to-back soundstage was drastically reduced from what we know possible with the same speakers in the the same room driven by different systems. In a multi-layered song like ‘Wish You Were Here’ (24/96 FLAC), instrument threads seemed to line along the plane of the speakers only, rather than stretching back in space as mixed. Brass sections and soloists were always rendered with real energy and power. Sometimes too much so, such as the raw horn and Hammond work in Jimmy Smith’s The Cat (24/96 FLAC). And here too, horns were altogether too entangled to discern each player’s contribution. Linn’s own criterion for understanding reproduction quality, the legendary Tune Dem, showed the Sneaky DSM erring decidely toward the tuneless here. Most AIFF tracks we tried refused to play. A BD album with 24/96 audio that we’d ripped with DVD Audio Extractor and converted from WAV to AIFF with XLD was one; but commercially released downloads always failed too, such as Cassandra Wilson’s New Moon (24/192 AIFF) from HDTracks.com, along with the Yes back catalogue in the same format. Linn explained that 24/192 AIFF music sold by HDTracks.com was the problem. ‘We have heard of issues of the music that has been sourced from HDTracks. These have an illegal character within the filename or metadata that causes the Linn DS to reject these Music files.’ Linn’s advice for Windows users is to use dBPowerAmp Music convertor, set to ‘convert’ from AIFF to AIFF. Mac users are advised to install Windows with a virtualisation package like Parallels and using the same program to transcode the files. While there was a huge dynamic soundscape trying to get out, gauged from various reference classical recordings, the sound always seemed just-removed from the room, a little papery, strings just the wrong side of reedy; Beecham’s delivery of Delius’ Brigg Fair (16/44.1 FLAC) strangely majored on tape hiss and creaky chairs and music stands, when it wasn’t dominated by screeching massed strings. We were more impressed that despite these irritations brass minded its manners better here in all its coppery sonority. Low-level playback was another issue. At quiet nighttime volume levels, music simply lost detail, and with it any interest. To sum up our impression of the Linn Sneaky sound, for some of the time the sound of the Sneaky DSM was not especially annoying. It had incredible dynamism, which might be unexpected for ‘only’ 33 W of power per channel. It could play without gross clipping; just with the magnification of HF glare that made us wince. It could play at lower volumes but in doing so lost much of the musical message, and the tone swung toward grey sibilance. It could keep in check the rhythms and timing of most music beautifully, often letting one get a sense of the tune. But in timbral and stereo spatial terms music would become a dog’s dinner that spoilt our appetite for toe tapping. This was a real curate’s egg, sounding to us like a £5,000 amplifier in its control and timing; and a £100 amp in terms of sweetness, tone and overall listener engagement. (See all audio reviews.)
