How small can a CD player be? If it's a portable with a flip lid and just one mini-jack output, the answer is little more than ten millimetres thick and a fraction bigger than the diameter of a CD.
But we don't reckon front-loading players will ever come much smaller than this Pro-Ject Projectbox, which has a top surface just 50 per cent bigger than one CD jewel case and height (including feet) equivalent to four of them.
What's the trick? The transport is of course a slot-loader, which saves a lot of the space that a tray would take up and the electronics portion is a single board, about 15mm by 150mm – with a grand total of six integrated circuits on it, including power regulators.
The slight cheat is the external power supply; Pro-Ject's usual wall-wart which outputs 16v AC. But the key really has been finding the right chips to make the thing work without larger components.
In turn, the crucial part of that process was selecting the DAC chip, which is a part intended for portable audio duty, including output circuits and everything else on board.
Time was when such components had a distinctly dodgy specification from an audiophile point of view, but the data sheet on this one suggests it is very capable – 96kHz compatible, good signal-to-noise ratio and so on.
True, it has a slightly less sophisticated digital filter than top-end parts, but the only real concession Pro-Ject has had to make is in maximum output: the DAC runs on a maximum 3.6v supply and as a result outputs just one volt, instead of the usual output of normal CD players. That means you'll need to wind up the volume control a bit further than usual, but any regular integrated amp will be driven well by one volt with volume set near maximum, so realistically this isn't a big sacrifice.
Operation is simple and efficient, with rapid disc-loading (six seconds), although searching is a bit slower. The tiny display (colour!) is highly legible and the matching tiny remote works well.
You don't necessarily expect the last word in refinement from a £300 component such as this, but we found a lot of detail and insight on offer. Perhaps, even more significantly, there's a lot of energy in the sound and it's easy to keep listening for a long session.
Play a well-recorded rock track and you'll revel in the powerful drum kit, or play a big opera chorus and get swept up in the excitement of dozens of voices and instruments in harmony.
Smaller-scale music is well served too. There's a touch of coloration on male voices, which adds some apparent resonance, but that's not unpleasant and it doesn't seem to affect female voices much.
The admirably neutral upper midrange is great for vocal intelligibility and, as a result, simple vocal tracks are really very communicative.
Above its weight
Deep bass is an interesting one. It seems very extended and has good weight to it when heard in isolation, but sometimes when there's a lot going on it fails to make quite the impact one has come to expect from a familiar disc.
Bass 'drive' is mostly a function of upper bass and that's consistently fine, but really low sounds from orchestral bass drum, the bottom string of a double bass and suchlike, can be a little underwhelming.
Treble, on the other hand, is sweetly extended with a good sense of 'air' and very natural decay into silence. In the lab, the player is very well-behaved, though with some noise-floor modulation (amplitude jitter), which may explain the bass effects noted.
Subjectively, it punches above its weight and will give good results in more than just office, PC and bedroom systems.
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