Project CD Box RS2T and Pre Box RS2 Digital
At a price of £2,200 and £1,900 respectively, Vienna-based Project Audio System’s CD Box RS2T transport and Pre Box RS2 Digital DAC are undoubtedly pushing at the upper limits of what many audiophiles are prepared to pay in order to listen to CDs. But while the transport is unapologetically designed – more on that in a moment – just to spin CDs, the DAC is an example of the current genre of multi-function hubs, combining digital to analogue conversion, analogue preamplification and headphone amplification in a single chassis.
Thus, while the DAC will accept a PCM data stream from the Project transport, or any other make of CD spinner for that matter, it will also handle inputs from a streamer or network player up to 32bit/768kHz, with full MQA unfolding and support for DoP and native DSD, depending on the input used.
Inside, low power consumption versions of ESS9038 Sabre DACs chips – one per channel – do the heavy lifting. There’s Bluetooth, plus the usual set of wired digital inputs including HDMI I2S, as well as analogue inputs via RCA and XLR sockets. Notably, the DAC has separate solid state and tube output stages, both fully balanced and both run permanently ‘hot’ so users can switch between them on the fly. In addition, there are seven optional digital filters and two analogue ones, along with switchable upsampling to 384/352.8kHz, giving users even more ability to tailor the sound output to their own preferences.
Project makes much of the fact that the top-loading CD transport uses a physical drive and electronic servo designed by Michael Jirousek, once a member of the CD design team at Philips. Lineage aside, the drive is certainly a technical tour-de-force, featuring a solid aluminium body which incorporates spring, silicon and carbon fibre vibration damping as well as Jirousek’s latest thinking on control circuitry. On the back of the transport are S/PDIF, AES/EBU, Toslink and HDMI/I2S outputs. If connected to the Project DAC via HDMI/I2S, the transport slaves to the DAC’s clock. Both the transport and the DAC are powered by SMPS bricks connected via umbilical cords to the rear panels, allowing Project to give the boxes a remarkably compact form-factor that would not look out of place as part of a desktop stack.
I tried the DAC as a stand-alone device, feeding it streamed and stored digital files via USB, and got results that, unsurprisingly, were indelibly printed with the sonic signature of the ESS DAC chips; a uber-detailed and somewhat insistent presentation of the kind that ESS Sabre fans – and there are a lot of them – love, but others, who prefer FPGA or R2R DACs, find rather wearying. It was an interesting diversion, and led me to conclude that the RS2 Pre DAC represents excellent value, given its all-formats digital capability, the degree of sonic shaping it allows, and its refined implementation of the popular ESS DAC chips.
However, it was not the reason that I had asked Project’s UK distributor Henley Audio for the loan stock. What I was really curious to see was whether Project’s claim to have produced a new flagship CD transport stood up to examination. On first inspection things did not look too promising; it was tempting to think: ‘small, lightweight, that’s how it’ll sound’. The first thirty seconds or so of the first disc reminded me just how dangerous it can be to draw such hasty conclusions: the already run-in sample, connected via AES to a Mola Mola Tambaqui DAC, sounded anything but a lightweight performer.
The keyboard pulses in the opening track of Ibrahim Maalouf’s album Red & Back Light were rendered with almost overwhelming weight and emphasis; a startling shift in tonal balance away from what I was used to towards the sonorous and brooding. Into the Tambaqui the RS2 proved to be a beast of a transport, delivering Massive Attack’s Unfinished Symphony with a low end power that had listeners boggling in astonishment and amusement. Even so, upon extended listening, it became clear that while it does exhibit an unusual degree of lower octaves emphasis, it does not do so wholly at the expense of midrange and top-end detail. That’s still there in the transcription, perhaps just not as prominently as some transports show it to be.
The experience prompted me to remove the Tambaqui, reuniting the Project Pre DAC and CD transport, and led to the discovery, who’d have guessed it, that Project has voiced the two components very much to partner each other. Paired, they exhibit a much more even-handed tonal balance and it was as such that the rest of the evaluation was conducted.
A transport intended to facilitate CD replay faces some notable technical challenges. Not only does the process of retrieving the data encoded onto the encapsulated foil in the silver disc turn out to be surprisingly susceptible to interference from vibration and electro-magnetic interference, but the rotation of the disc platter needs to be linearly reduced as the data are read from the centre of the disc to the outside edge. The more the error correction circuity is forced to intervene as noise hampers data transfer, the harder and glassier becomes the resulting sound. It’s why, when manufacturers realised that early transports actually were a long way from the much heralded ‘Perfect Sound Forever’ designers started to pay closer attention to the business of rotational accuracy, electrical noise and vibration.
One technical response to this trilemma has been that by Japanese company CEC whose commercially successful series of belt-drive transports are notable for extremely low electrical noise levels. In part, CEC’s scheme results in such low noise - and hence superior data retrieval accuracy – because using belts rather than direct drive allows the potential noise and vibration of the rotation and laser sled motors to be kept away from the sensitive read head.
But putting distance between the motors from the read head is not the only route to low noise; other manufacturers, including Philips back when it dominated the global market for OEM CD drives, have concentrated on noise reduction through among other strategies, rigorous quality control of motors, electrical screening, physical suspension and exceptionally smooth power supplies.
That Jirousek has indeed advanced CD replay, if not quite for masses, certainly for a significant well-heeled cohort of middle-tier buyers, is not in doubt. His drive, as implemented in the RS2T CD transport, is very electrically quiet, able to present its partnering DAC with a level of microdynamic and tonal detail that while perhaps not class-leading is nonetheless an extremely strong performer for the money.
Project’s target buyers for the RS2 combination are likely to be audiophiles who already own sizeable collections of CDs. They have probably dabbled with streamers in the £3-5k price bracket but have found them ultimately unsatisfactory from a sonic performance perspective. Project is banking on them trying the RS2 combination and getting fresh value from their CD collection, hearing from familiar recorded material such a seductive level of un-forced naturalness and detail that they whisper a silent prayer of thanks that they had not in a rash moment sold off their collection of silver discs.
Certainly, compared back-to-back with streamers in the sub-£5k bracket, the Project RS2 combination gave an emphatic, unequivocal demonstration of sonic superiority; most notably in the way it transcribed dynamic expression and ‘you are there’ spatial effects. Rips and streamed copies sounded more or less flatter and less engaging than physical CDs of the same recordings and while there may be any number of reasons why this is so, I don’t think the majority of buyers will care overly-much about any of them. If for them the convenience of streamed or network played is still trumped by sonic quality, then the RS2 combination will be the walk-away winner.
Of course, with the Pre DAC, Project is hedging its bets; as already noted, it is a flexible and capable device able to support digital delivered by USB, as well as steam-powered analogue signals too. It is therefore strong value as a stand-alone, but if that’s how buyers treat it, I think they will be missing out. In partnership with the RS2T transport, the Pre DAC’s capabilities are more fully exploited; together the two boxes making a very compelling case for CD as a seriously audiophile option.
Towards the end of my time with the Project pair I was loaned an after-market disc puck, designed as an alternative to Project’s standard aluminium device. The QStab by German company HEADquarter Audio is 3D printed from a bone-like material. The company also makes almost identical devices for transports that use the Philips CDM 4 and CD Pro 2 drives. Placed onto a CD in the Project RS2T, the QStab covers much of the disc surface, the bone-like material machined perfectly flat on its underside, pulled into gentle contact with the label side of the CD. The sonic impact of this apparently simple change was quite marked and I was reminded of a truth spoken by HiFiCritic founder Martin Colloms about after-market tweaks in general: “It’s easy to change the sound, but not always for the better.”
In back-to-back comparison to the standard Project aluminium puck, the QStab gave the transport a slightly greater degree of tonal depth and complexity, apparent through the audio band but particularly notable in the lower frequencies, while at the same time making the transport sound more relaxed, with an enhanced sense of musical flow. With the Project RS2T, the QStab can therefore be said to be a tweak that changes the sound for the better. This finding was not wholly unexpected, since ‘wam reviews editor George Sallit reported a similar reaction when he tried a QStab on his Jay’s Audio CDT2-MK3 transport. HEADquarter Audio seems to understand something useful about the important role of resonance in CD replay.