Click to see the AKG N5005 YouTube presentation video.

On March 27, I attended an introduction to the new AKG N5005 reference class in-ear headphones taking place in London, UK. These new headphones, first unveiled at CES 2018, use the Harman IE Target Curve, as discussed in the recent Audio Engineering Society papers by authors Sean Olive, Todd Welti, and Omid Khonsaripour (   www.aes.org/e-lib/19237- part 1 dedicated to on-ear headphones and    www.aes.org/e-lib/19275- part 2 , which measures in-ear headphones) from Harman International.

 

A small group of journalists was invited for this rather special event, planned essentially for the lifestyle press. Of course, the AKG N5005 will get attention from all the more marketing-oriented press, but they are not exactly the audience for the stage set by Dr. Sean E. Olive. Simply because his presentation, or better yet his lecture, was about the science behind the development of the AKG N5005, which inspired me to write this brief report for the more technical-minded audience of The Audio Voice, even though I was there on assignment from Dutch magazine HVT, for which I write regularly.

 

The first thing Olive stated was that there was hardly a correlation between user preference in terms of the frequency response of a headphone (in-ear, on-ear, or around ear) and its price. The graph with the results of the research conducted by Harman, based on a large selection of headphones, was very clear about that. Worse, the correlation between perceived quality and price, based on listening tests, was definitely not good. In the past, Olive and his team defined the so called "Harman target curve," a frequency response curve that fits best with perceived quality. For further study on this subject no less than 283 headphones were compared to this Harman curve. 

 

Listening tests were done with listening groups, and a large controlled variety of listeners (trained, untrained, sex, age, countries, culture, etc.). Besides the variety in the listeners' sampling, careful attention was given to perfect fitting, as leakage can greatly influence the results. After a lot of statistical work on all the collected data, a model emerged in which accurate, statistically relevant predictions could be made with respect to frequency response and perceived quality. The results of this study were applied to the development of the AKG N5005.

Sean Olive during his presentation, detailing the extensive Harman research on user preferences and target frequency response curves for in-ear headphones.

The N5005 is a customizable reference class five-driver configuration in-ear headphone. That means everything is special with this product. From the high-gloss piano black ceramic, chosen for its strength, durability, color depth, and scratch resistance, to the choice of drivers, with a 9.2 mm paper membrane driver selected for the lower frequencies, complemented with two mid-range- and two high-range balanced armature drivers, providing a 10 Hz to 40 kHz frequency range.

 

From the Harman research, it was clear that younger people prefer a bit more bass. Therefore, the N5005 comes with four filters, which enable the customization of the frequency curve. The factory response corresponds to the reference curve. The remaining four filters are described as Bass Boost, Reference Sound, Semi-High Boost, and High Boost.

 

Another issue is the proper fit of in-ear headphones. Not only is this a comfort issue, but also leakage will alter the perceived quality, making the fit extremely important. The N5005 comes with four ear-tips in different sizes and three SpinFit ear-tips also in different sizes, ensuring a perfect fit for different usage scenarios. 

Designed to reproduce high-resolution audio sources, the N5005 uses a hybrid of one dynamic and quad BA drivers to create an extraordinary five-way in-ear experience.

Unlike the previous flagship AKG K3003, the N5005 comes with high-quality detachable twist cables. The detachable cables make replacement easy if a cable gets damaged and enables cables to be easily adaptable to the user's preference. The same MMCX cable connection is used throughout. The two twisted wire cables include a balanced 2.5 mm version and a 3.5 mm Android and iOS cable with control unit. With this unit, which incorporates a microphone and controls for music and speech, there is also a switch to choose between Android and iOS. Another important added feature is a Bluetooth 4.1 dongle with aptX and AAC audio support, which features a three-button universal remote mic. The AKG N5005 delivers up to eight hours of battery life in wireless mode.

 

Also handy is the included two pin flight adapter and a cleaning tool, provided to keep the N5005 in optimal condition. Each individually serial numbered headphone comes at a price - $999.95. According to Harman, the N5005 is targeted at users who want the best in every aspect and who will be able to appreciate the product quality.