Fostex TH-909 Premium Open-Back 1.5 Tesla Stereo Headphones

### Editorial Review of the Fostex TH-909 Headphones The Fostex TH-909 headphones are an ambitious take on open-back headphone design by a brand renowned for its closed-back innovations. Positioned as a flagship model, the TH-909 utilizes a striking dual-layer open grille that aims to enhance sound performance while maintaining the hallmark luxurious feel of Fostex's Urushi lacquer cups. Customers have observed that the design closely resembles the acclaimed TH900 but with notable sound tuning changes. The TH-909 shines with a redesigned voice circuit that offers a pronounced midrange boost, effectively bridging the gap between heavy bass and vocal clarity, though it can occasionally veer into 'shouty' territory on certain tracks. This tuning delivers a rich, full-bodied sound ideal for acoustic and vocal music, while retaining a sparkle in the high frequencies characteristic of Fostex. In terms of technical performance, these headphones impress with their phase uniformity—a key aspect for accurate sound staging—boasting superior metrics compared to some competitors in the high-end category. The TH-909 presents a low impedance of 25 ohms, which presents unique challenges when pairing with amplifiers, suggesting that lower power levels yield better results, contrary to typical audiophile practices. Overall, the Fostex TH-909s have received a blend of admiration and caution from audio enthusiasts. They are praised for their engaging tuning and build quality; however, they also come with a learning curve regarding amplification compatibility. For those willing to experiment with pairing, these headphones can provide an enriching listening experience. ### Pros and Cons **