For some of you, the pitiful whinings of frequent fliers fall on deaf ears (if you'll pardon the expression). Why should you give a hoot about the poor dears when they bitch about in-flight noise as they make their way to the Seychelles? In which case, skip this review, because the product is of interest ONLY to audiophiles who fly with great regularity. Frankly, I can't imagine many other uses for noise-cancelling headphones, when workers in noisy conditions, e.g. jackhammer operators, wear government-mandated protection.

Noise-cancelling headphones aren't new, but Sennheiser's latest are interesting for a few reasons. Firstly, they're not obscenely-priced, at only £89.95 per pair. Secondly, they actually sound OK in headphone-only mode. Thirdly, they work at reducing perceived noise so well that the specification - stated at a seemingly unimpressive -10dB between 100 and 400Hz - is meaningless: you know the instant you switch on the noise-cancelling circuitry that your trip will be that much less stressful.

As with the PX100 portable headphones, the PXC 250 is an ultra-compact, fold-flat model weighing only 65g. The 'kit' includes a carry case with belt loop with a pocket for the supplied headphone plug adaptors and space for a small portable player. It uses the company's advanced Noisegard active electronic noise reduction system in a closed design for even more noise reduction; the NoiseGard element consists of tiny microphones inside each earpiece that 'listen' to the ambient noise. This noise is then reversed in phase and fed back into the earpieces, the out-of-phase signal cancelling the real noise. The closed cups also endow the headphone with acceptable bass yet - surprisingly - still allow you to hear in-flight staff asking if you can stomach a BA cheese roll. Thus claims that speech will still be intelligible are true; the PXC 250 works mainly on the distressing thrumming of the engines.

As expected, the PXC 250 also improves on the headphones airlines supply for listening to the in-flight entertainment. For the first time in years, I actually watched a couple of films on a long flight, finding the dialogue clear enough to absorb; my previous reticence had everything to do with poor sound and not poor (or small) visuals, so, thanks, Sennheiser. The PXC 250 sounds like a good £30 headphone; think of the other £60 as the price of relief.

Halfway down the fitted 6ft cable is a dildo-like cylinder holding two AAA cells, fitted with pocket clip, on/off button and a red-telltale. Switch on, and the noise cancelling takes place instantaneously, so you can do a quickie A/B even in the relatively quiet environment of a hi-fi shop to hear the effect. Hop on a plane and Sennheiser reckons you'll be able to listen at lower levels, reducing the risk of hearing damage, suffer less stress and still hear staff tell you to grab your life jacket and kiss your arse goodbye.

As headphones go, they're very much of the modern school, suitable for both for low-impedance portables as well as high-impedance in-flight entertainment systems. They were designed to take up little space and add little weight, AND they're comfortable enough to leave on for a transatlantic flight. On the noise-cancelling side, the electronics module runs for 80 hours on the two cells, and if they run out, you can still use the NoiseGards as normal headphones.

Sorry to use a cliché, but I'll never leave home without them again. At least, not when leaving home means boarding a plane.