Released in October 2012, Sony MDR-1R bears the number "1" in its model name, which indicates the manufacturer's current reference sound signature. Starting from the classical MDR-1, the naming has been passed on to Q010-MDR1. As Sony's new reference model, 角田直隆-san, who is in charge of acoustic design & the mastermind behind the development of E888, D777, and Q010, implements the wide-bandwidth HD driver, and the BRC(beat response control), which is perhaps the most intriguing feature of 1R.
"特に低域の使い方に違いがあり、80から90年代にかけては100Hzにピークがあったものが現在のエレクトロニカなどの音楽では30～40Hzにピークが来るのです。このベースの音色をきちんと再生できないと音楽そのもののバランスも崩してしまう。これまで手本としてきたMDR-CD900STよりもさらに下の帯域にピークがあるので、音の設計に関してもだいぶ考えを改めなければとそこで気付いたんですね。" http://www.sony.jp/headphone/special/park/products_m1/tech1.htmlConventionally, Sony's target frequency of interest has always been at 100 Hz, as that is where the majority of low frequency contents have been located with traditional music. However, the time's changed: In order to accommodate the current music industry's demand of low frequency reproduction at as low as 30 - 40 Hz, 角田-san develops a special damping system.
"さらに低域再生という点ではハウジング上に設けたポート（通気孔）によって低域の過渡特性を改善させるビートレスポンスコントロール（Beat Response Control）を導入しました。振動板の動作を最適化することで30～40Hzのリズム感も改善され、立ち上がりや立下り特性も向上しています。" http://www.sony.jp/headphone/special/park/products_m1/tech1.htmlBy optimizing the air compliance within the housing using two rear vents and a frontal resistive opening, a great damping over the driver's transient has been accomplished, according to the manufacturer.
CON: There is an audible ringing at 10 kHz, but it can be knocked off easily with a simple trick. Please refer to the second thought #2.
ON SECOND THOUGHT #1: Few brilliant tweaks are implemented here by Sony in order to increase the perceived the low frequency response: First, there is a time-delayed sub-bass filling up the gap at 20 - 100 Hz. Second, the level of second-order distortion, which promotes warmth, is quite strong, reaching 3 ~ 5% at 20 Hz. A great job done by Sony.
ON SECOND THOUGHT #4: There has been a request of modification with MDR-1R from a friend, as he finds the mid-bass too emphasized, or the sub-bass too weak. So I'll work on the modification of 1R pretty soon. Stay tuned!