AKG's K451 headphones have been around for a few years now, and as such the price has plummeted from the once hard to justify £80 RRP. You can typically pick up a pair today for less than £40, a price that's much easier to swallow. Any reservations I had towards the K451 were based solely around the original RRP and focused mainly on build quality, which didn't quite match up to the price. At £40, however, the shortcomings are easier to accept and the K541 actually becomes something of a bargain.

The K451 is a pair of supra-aural (on-ear) headphones, meaning the cans sit on top of your ears rather than surrounding them, to avoid completely blocking out all ambient sound. The earpads are made from a soft faux-leather, which is reasonably comfortable for short listening sessions, but after extended use I did find my outer ears were becoming slightly fatigued and a little too warm. This is an unfortunate side effect of many supra-aural headphones, however, and not unique to the K451. The earpads slide up and down a metal rail, but this is where build quality concerns begin to arise. The rail feels sharp and rough, and the plastic headband feels cheap. Plastic is used elsewhere, including on the closed earcup backing but, again, it's not a major criticism at this price.

The design is rather inconspicuous, with a predominantly black colour scheme paired with silver accents on the back of each ear cup. The vents on the back are merely for show, as the drivers are closed-back rather than open-back - making sure the K451 stays travel-friendly. The ability to fold to a more travel-friendly size is a welcome one too.

The cable is detachable and locks into the left earcup with a rotating lock, so you'll be confident it won't come out. The earcups rotate on a pivot and can be folded up towards the headband. A sturdy and rigid travel case is included, for stowing the headphones away from harm. In fact, the carry case might be one of my favourites in terms of providing useful protection. You can buy headphones costing three times as much and still not find a better carry case.

^ There's a three-button inline remote control and microphone that works with iOS devices and terminates in a standard 3.5mm jack

The K451 sounds great for the money - pair it with a smartphone and you have a winning combination when on the move. There's a good weight to the lower frequencies, aided by a frequency response that goes from a surprisingly low (for the price) 11Hz all the way up to 29,500Hz. Mids and trebles, too, have decent presence, although are perhaps a little subdued by the lower frequencies. These occasionally have a penchant to impinge over into the mid-range. Still, for the price you're paying you'll be hard-pressed to find a better pair of on-ear headphones. Listening to a Menahan Street Band track, the brass came through with a delightful degree of brightness that belies the bargain-price.

Overall, the AKG K451 is a pair of headphones that isn't targeted towards audiophiles, but at commuters looking for a convenient, portable pair to carry with them. For this purpose I don't hesitate to recommend them. Given the low price, they're tough to beat for sheer value, and the sturdy carry case is the icing on the cake. My other favourite £40 headphones are the decidedly more outlandish-looking Skullcandy Grind , so if you want headphones that make more of a statement, they are also worth considering and also fractionally beat out the K451 predominantly for comfort.

If those don't quite suit your needs either, then be sure to check out our regularly-updated Best headphones list.