Audio Technica have already established themselves as one of the élite amongst manufacturers of professional studio microphones, and now it is evident they intend to continue their marketing thrust into the professional studio by building headphones.
The two pairs of headphones under review, the ATH M40s and the ATH D40s, are similar in most respects, the only real difference being that the M40s have a wide, flat frequency response, while the D40s have a degree of bass enhancement built in to accommodate the needs of musicians using the phones for performance monitoring (see the 'Phoning Around' box for more information on headphones).
Both sets of phones follow the enclosed format, and each phone can swivel through a full 180 degrees, which makes it easier for people who like to work with one phone on and one phone off. The comfortably padded earpads sit on the ear itself rather than enclosing it, and the padded headband is fully adjustable.
On the outside of the phone enclosure is a small downward-facing port (presumably associated with the tuning of the acoustic system) each phone is embossed L and R so you know which way round to wear them. A Neodymium magnetic system is used to drive the 40mm diaphragms which are wound with copper-clad aluminium wire to maintain a low mass. The maximum rated input power is 1.6 Watts, but I think that most people would be well on their way to a serious headache by then. A clean SPL of 100dB is available, but for extended use it is probably unwise to exceed 90dB.
Considering that these are studio headphones, a couple of points surprise me. First of all, there's no manual, just a few brief facts printed on the back of the box. Secondly, the cable entering via the left headphone is fixed, rather than being connected via a plug, which means that if you trip over the lead, you may well damage it beyond repair. On a similar note, the ear pads don't appear to be removable for cleaning.
When it comes to performance, both sets of phones produce a smooth but highly detailed sound, with excellent stereo imaging, and good bass extension. As expected, the bass on the D40s is hyped up slightly, but not to the extent where it feels unnatural. For drummers and bass players, this characteristic will probably be very welcome.
In conclusion, while on the performance side the ATH D40 and ATH M40 are extremely capable and nice-sounding headphones, they don't have the serviceability that we've come to expect from the established players in the studio headphone marketplace. I've already mentioned the fixed cable, but with professional headphones you also expect to be able to replace the majority of the parts while in the field. In short, I feel these phones are built more like a high-end domestic product than a pro audio tool, which for an RRP of almost £120 may be, in the words of our (current) Prime Minister, "rather inappropriate".
Since headphones require very small amounts of electrical power to produce massive SPLs at the ear, the diaphragm assembly can be made sufficiently light that a single transducer can cover a far wider frequency range than a loudspeaker monitoring system. While a studio loudspeaker system might go from 35Hz to 22kHz, the ATH M40s under review here run from 5Hz right up to 28kHz. What headphones don't provide is the physical impression of bass -- you only hear the sound, you don't feel it in other parts of your body. Furthermore, as achieving an accurate bass response depends on how well the phones couple to the ears of the listener, people with differently shaped heads or ears may perceive varying levels of bass. This being the case, I've always advocated that when it comes to mixing, headphones should be used in conjunction with loudspeakers, and never alone.
Traditionally, open-ear headphones produce the most neutral sound, though at the expense of a less impressive bass end than fully-enclosed models. Enclosed models can deliver surprising amounts of true bass, but the fact that they are enclosed can produce a slightly coloured sound. However, they are useful when several musicians are playing together, as they help shield the wearer from external sounds and are used for performance monitoring, where absolute fidelity isn't usually as important as volume and freedom from sound leakage.
Open phones are more likely to be used for mixing or qualitative analysis, and while they offer relatively poor isolation from external sounds, some performers still prefer them, because they don't feel so acoustically cut off.
Smooth, detailed sound.
Low sound leakage.
Not field serviceable.
Fixed cable connection.
Technically impressive and well-suited to private studio use, but the
lack of field serviceability could be a problem in a commercial environment.
£ £119.95 inc VAT.
A Audio-Technica, Technica House, Royal London Industrial Estate, Old Lane, Leeds, LS11 8AG.
T 0113 227 1441.
F 0113 270 4836.