Fostex ET-TH4.4BL
Complementary products
Overview
A short, flexible cable designed for 4.4 mm balanced connection. The ET-TH4.4BL uses 7N-grade OFC copper and a gold-plated source-side termination. It connects to Fostex TH-series headphones via the range’s proprietary 2-pin bayonet connector system. With its 2-meter length and PVC sheath, it follows the logic of Fostex optional cables: same materials, same manufacturing philosophy, different termination.
Why a 4.4 mm balanced version
Fostex has long offered 6.3 mm jack and 4-pin XLR cables for its premium headphones. The ET-TH4.4BL completes this lineup with a 4.4 mm TRRRS Pentaconn termination, a five-pole format developed in Japan and adopted by Sony, Sennheiser, FiiO, and TEAC on their high-end amps and DAPs.
Balanced connection separates the left and right signals with their own ground returns, eliminating the shared conductor found in a conventional single-ended connection. The fifth pole of the 4.4 mm connector serves as overall shielding; it can also be used to establish a common ground when the headphone is connected to a mains-powered hi-fi system, reducing the risk of ground loops.
Construction and materials
The conductor is OFC copper rated at 99.99999% purity (7N grade). This designation, common in the Japanese audio industry, indicates oxygen-free copper with very few residual impurities. Fostex uses this same grade across all its optional cables for the TH series, from jack to XLR versions.
The outer jacket is PVC. Fostex describes it as supple and easy to handle, a pragmatic choice for a 2-meter cable that will often be used with a portable player or a desktop amp. The total weight is 90 grams, less than the 3-meter cables in the range (120 to 130 g depending on the version).
Headphone-side connectors
The ET-TH4.4BL uses the Fostex proprietary connection system: two 2-pin plugs with quarter-turn bayonet locking. This system has equipped all TH-series headphones since the move to detachable cables. The connectors are gold-plated with rhodium finish, identical to those on the brand’s other optional cables.
Usage and positioning
A 2-meter cable is suitable for desktop use or portable use with a player worn on a belt or in a pocket. For armchair listening with an amp positioned further away, the 3-meter cables (ET-H3.0N7BL in XLR, ET-H3.0N7UB in jack) are still more appropriate.
The 4.4 mm format requires a compatible balanced output. You’ll find this format on Sony Walkman players (NW-WM1A, NW-WM1Z, NW-ZX300 and successors), on some FiiO, iFi, TEAC, or Sennheiser (HDV 820) headphone amps, and on a few recent desktop DAC/amps. Owners of amps with only 4-pin XLR outputs will need to choose the ET-H3.0N7BL cable or use an adapter.
Technical features
Cable
- 7N (99.99999%) pure OFC (oxygen-free copper) conductor
- 5-pole balanced configuration
- 4.4 mm jack connector
Connectors
- Gold-plated plug
Construction
- Flexible PVC jacket, easy to handle
Dimensions and weight
- Length: 2.0 m
- Weight: 90 g
Compatibility
- Compatible models: TH1100RP, TH1000RP, TH909, TH900mk2, TH808, TH616, TH610
Frequently Asked Questions
Can this cable be plugged into a standard 3.5 mm or 6.3 mm headphone jack?
No. The 4.4 mm Pentaconn plug is physically incompatible with standard jack outputs. You would need a 4.4 mm to jack adapter, but that would negate the benefit of the balanced connection since the source output would remain single-ended.
What sound difference can be expected compared with the stock jack cable supplied with the headphones?
Balanced connection can offer better channel separation and a lower noise floor, especially with amps whose balanced stage is of higher quality than the single-ended stage. The improvement is highly dependent on the quality of the upstream amplification.
Does the cable work with the older TH900 (first generation) or TH600?
No. These older models had a hardwired, non-detachable cable. Only the headphones listed in the product sheet (TH1100RP, TH1000RP, TH909, TH900mk2, TH808, TH616, TH610) feature the 2-pin bayonet connector system.
Is the 7N copper grade measurable or verifiable?
Fostex uses this designation across all its optional cables for the TH series. The “N” grade (number of 9s in the purity percentage) is a common convention in Japan, but options for independent verification are limited once the copper has been processed into a finished cable.
Is there a longer 4.4 mm version of this cable?
No, Fostex currently offers only this 2-meter version with 4.4 mm termination. For a longer balanced connection, the 3-meter XLR cable (ET-H3.0N7BL) remains the only official option.
- Eco-contribution included in the sale price.