TH909(SB)
Premium HeadphonesThe proprietary BioDyna diaphragm. The TH909 open-type premium headphones, with acoustic tuning that brings out its high potential, are now available in a limited number of limited color versions.
Newly developed open-type high-end headphones based on Fostex's most acclaimed headphone ever, the TH900mk2
Features
![](https://www.fostex.jp/cms/wp-content/uploads/2018/09/TH909_main-text-980x407.jpg)
![](https://www.fostex.jp/cms/wp-content/uploads/2018/09/bio-dyna-300x191.jpg)
BioDyna diaphragm made of ultra-fine bio-cellulose fiber material is used.
Utilizing know-how accumulated over many years, bio-cellulose fibers are blended with other fibers and other materials under optimal conditions. Low specific gravity, high Young’s modulus and high internal loss are realized. In addition to reproducing delicate, high-resolution and beautiful mid-high frequencies, the free edge with good linearity faithfully reproduces low mid-range frequencies with large amplitude.
BIODYNA” and “BIODYNA” are registered trademarks of Foster Electric Co.
What is Biocellulose Fiber?
Bio-cellulose fiber is made by advanced biotechnology and is an ultrafine fiber with a thickness of 20 to 50 nm (nanometer), about 1/1000 of natural plant fibers (such as cotton). These fibers are extremely pure α-cellulose, with almost no harmful impurity components, and exhibit the highest level of crystallinity. The ultrafine bio-cellulose fiber has excellent reproduction ability in the mid and high frequencies. When various fibers are combined with this fiber in an appropriate blend, a sound quality that combines the characteristics of each fiber can be obtained, enabling sound creation of a higher level. We have established a technology for mass-producing high-performance diaphragms by blending bio-cellulose fibers with other fibers under optimal conditions, utilizing the know-how we have accumulated over many years.
● Magnetic circuit with repulsive magnetic field is equipped with an ultra-strong driver unit with a magnetic flux density of 1.5 Tesla.
A low distortion, ultra-strong, high-performance magnetic circuit with a magnetic flux density of 1.5 tesla using neodymium magnets provides a vast dynamic range.
Housing with lacquer and Bordeaux finish that satisfies the pleasure of ownership along with high quality sound
The surface of the wood part is finished with a lacquer craft originally developed by SAKAMOTO Otsuzo Shoten, a company founded in 1900 that applies traditional Japanese craftsmanship to today’s industrial products. The lacquer used is black lacquer for the base and adhesive lacquer for the foil application. In order to express a prestigious sense of depth, various kinds of colored silver foils are smoked with sulfur and pasted like chigiri-e (tear-off pictures).
Wood quality: Mizume cherry
Mizume-zakura is a variety of birch, a specialty of Japan. The wood is handcrafted by skilled craftsmen exclusively for TH909.
Dual aluminum etched parts in the housing opening
The aperture has an ingenious design with a double arrangement of etched aluminum parts that give a different impression depending on the light and accuracy of the light. The aperture ratio and the numerous fine-tuning of each internal part reproduce a natural sound field that is comfortable and comfortable to listen to.
7N grade high-purity OFC unbalanced cable (ET-H3.0N7UB) included
The unbalanced cable comes with a 7N (99.999999%) grade high-purity OFC (Oxygen Free Copper) unbalanced cable, which is essential for achieving high resolution and expressing the glossiness, and has high transmission capacity by eliminating impurities to the utmost limit. The plug sleeve is made of highly durable duralumin.
The unit is equipped with a detachable connector port and uses 7N grade cables for internal wiring.
Features a detachable connector terminal with rhodium-plated treatment for high hardness, abrasion resistance, and corrosion resistance, and a detachable contact terminal on the headphone body side. Balanced connection is also supported with an XLR-terminal cable (ET-H3.0N7BL) (sold separately).
Ear pads with low-resilience cushions to reduce sound leakage
The earpads are specially designed with low rebound cushions that cover the back of the ears to reduce sound leakage, and carefully selected high-grade synthetic leather to provide a pleasant feel and comfortable fit even after prolonged use.
Bio-cellulose fiber is made by advanced biotechnology and is an ultrafine fiber with a thickness of 20 to 50 nm (nanometer), about 1/1000 of natural plant fibers (such as cotton). These fibers are extremely pure α-cellulose, with almost no harmful impurity components, and exhibit the highest level of crystallinity. The ultrafine bio-cellulose fiber has excellent reproduction ability in the mid and high frequencies. When various fibers are combined with this fiber in an appropriate blend, a sound quality that combines the characteristics of each fiber can be obtained, enabling sound creation of a higher level. We have established a technology for mass-producing high-performance diaphragms by blending bio-cellulose fibers with other fibers under optimal conditions, utilizing the know-how we have accumulated over many years.
![](https://www.fostex.jp/cms/wp-content/uploads/2018/09/548843_assy-300x115.jpg)
● Magnetic circuit with repulsive magnetic field is equipped with an ultra-strong driver unit with a magnetic flux density of 1.5 Tesla.
A low distortion, ultra-strong, high-performance magnetic circuit with a magnetic flux density of 1.5 tesla using neodymium magnets provides a vast dynamic range.
![](https://www.fostex.jp/cms/wp-content/uploads/2018/09/TH909_housing-300x191.jpg)
Housing with lacquer and Bordeaux finish that satisfies the pleasure of ownership along with high quality sound
The surface of the wood part is finished with a lacquer craft originally developed by SAKAMOTO Otsuzo Shoten, a company founded in 1900 that applies traditional Japanese craftsmanship to today’s industrial products. The lacquer used is black lacquer for the base and adhesive lacquer for the foil application. In order to express a prestigious sense of depth, various kinds of colored silver foils are smoked with sulfur and pasted like chigiri-e (tear-off pictures).
Wood quality: Mizume cherry
Mizume-zakura is a variety of birch, a specialty of Japan. The wood is handcrafted by skilled craftsmen exclusively for TH909.
![](https://www.fostex.jp/cms/wp-content/uploads/2018/09/TH909_etching-300x191.jpg)
Dual aluminum etched parts in the housing opening
The aperture has an ingenious design with a double arrangement of etched aluminum parts that give a different impression depending on the light and accuracy of the light. The aperture ratio and the numerous fine-tuning of each internal part reproduce a natural sound field that is comfortable and comfortable to listen to.
![](https://www.fostex.jp/cms/wp-content/uploads/2018/09/TH909_cable-300x191.jpg)
7N grade high-purity OFC unbalanced cable (ET-H3.0N7UB) included
The unbalanced cable comes with a 7N (99.999999%) grade high-purity OFC (Oxygen Free Copper) unbalanced cable, which is essential for achieving high resolution and expressing the glossiness, and has high transmission capacity by eliminating impurities to the utmost limit. The plug sleeve is made of highly durable duralumin.
![](https://www.fostex.jp/cms/wp-content/uploads/2018/09/2pin_connector-300x265.jpg)
The unit is equipped with a detachable connector port and uses 7N grade cables for internal wiring.
Features a detachable connector terminal with rhodium-plated treatment for high hardness, abrasion resistance, and corrosion resistance, and a detachable contact terminal on the headphone body side. Balanced connection is also supported with an XLR-terminal cable (ET-H3.0N7BL) (sold separately).
![](https://www.fostex.jp/cms/wp-content/uploads/2018/09/earpad_99-300x191.jpg)
Ear pads with low-resilience cushions to reduce sound leakage
The earpads are specially designed with low rebound cushions that cover the back of the ears to reduce sound leakage, and carefully selected high-grade synthetic leather to provide a pleasant feel and comfortable fit even after prolonged use.
Specifications
Main Specifications
Type | Open and dynamic type |
---|---|
Driver | φ50mm neodymium magnet / BioDyna diaphragm |
Frequency response | 5 to 45,000 Hz |
Impedance | 25Ω |
Sensitivity | 100dB/mW |
Maximum input | 1,800mW |
Weight | Approx. 390g (excluding cord) |
Cable | 3m Y-type 7N-OFC wire (detachable) |
Detachable terminal | 2-pin (Terminal: gold-plated base, rhodium-plated specification) |
Plug | 6.3mm diameter gold-plated stereo standard plug |
Accessories | Headphone stand, leather pouch |
Attention
After use, wipe sweat, sebum, hair styling products, foundation, etc. adhering to the earpads and headpads with a dry cloth.
●Ear pads are consumables. Please replace them as needed because they deteriorate due to daily use and long-term storage.
*This product complies with the European RoHS Directive.