Inside the earcups, the Q701s offer the same flat-wire voice-coil technology, 'Varimotion' multilayer diaphragm, and neodymium magnet system that AKG developed for its studio headphones. The result is a claimed frequency response range of 10 Hz to 39.8 kHz - on a par with headphones costing north of £1,000 including the much-lauded Sennheiser HD800s and Grado GS1000s. That should explain why Quincy Jones believes: ‘These are the only headphones I’ve heard that bring out the true sound we were striving for on records like “Billie Jean”‚ “Thriller” and “Give Me the Night“. It’s the best-quality sound I’ve heard, ever.’
The AKG Q701s come with both a 3m and a 6m length of detachable cable. Considering these are headphones that you'll want to hook up to a proper Hi-Fi set-up while lounging in an armchair, the inclusion of a longer cable is a particularly useful on - saving an otherwise inevitable extra purchase. It's worth noting that these cables use proprietary connector at one end, so replacement - if necessary - will prove a pain. At the far end from the headphones, the Q701's cable terminates in a 3.5mm jack, and a 3.5mm to 6.25mm adaptor is supplied, which screws into place keeping it secure.
The decision to make the default connector on the cabling compatible with portable media players isn't the best indicator of where the Q701s perform best. The Q701s aren't easily driven. Trying to use them directly from an iPhone the result was decidedly lacklustre - even at full volume there simply wasn't enough power - which isn't necessarily a problem, but is worth considering, bearing in mind that the likes of Grado's SR325s are easily driven enough that, if you do want to use portable player, they'll try their hardest to make it sound at least half-decent.
Attached to a more suitable source device, the Q701's really shine. AKG makes big claims about the accuracy of these headphones, and we're not about to dispute them. Even with just 320kbps MP3s the Q701s draw an impressive amount of detail out of recordings. Listen to lossless files, or good old-fashioned CDs and the results are nothing short of astounding, given the price of the Q701s.