Get past the star rating if you can. Yes, the EF5 is flawed, but we have no doubt there are some people that will like what this headphone amp does.
Your £300 buys two boxes: one is a dedicated power supply and the other contains the amplification circuitry.
The amplifier stage is a hybrid design: part valve (the valve sticking out of the top panel is a big clue, of course) and part transistor. The idea is to combine the sweetness of valves with the grip that they so often lack.
The EF5 lives up to all the valve stereotypes: it's smooth, full-bodied and organic sounding. Take a listen to Charlotte Gainsbourg's IRM set and we have no doubt you'll be impressed with the passion, intimacy and midrange fluidity on offer.
In fact, feed the EF5 anything small-scale or acoustically based and it'll impress with its warmth.
However, things soon change for the worse when the material is changed for something that provides plenty of punch and requires a decent degree of rhythmic precision.
Soft centre is hard to swallow
Play Timbaland's Shock Value II – or even Beethoven's 5th Symphony for that matter – and things start to fall apart.
The EF5 is soft-centred, lacking the tautness and dynamic reach to make music like this work well. The result is a notable drop in excitement, and no matter how pleasant a product sounds, any loss in this department isn't a good thing.
Move away from sonic performance and you'll find the feature count is limited. There's only one input and a single headphone output. There's also a gain switch.
The EF5 is a smooth, refined listen. We're pleased to hear that, but we want more bite to our sound, and that's something this headphone amp doesn't deliver.
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