Sony SxS

Technical Details

SxS cards utilize the ExpressCard/34 specification with a PCIe 1.0 interface, achieving theoretical transfer rates of 2.5 GB/s. In practice, SxS-1 cards deliver a constant 35 MB/s, while SxS Pro+ cards reach up to 440 MB/s sustained write. The cards measure 75 x 34 x 5 mm and weigh 15 grams. Three main variants exist: SxS-1 (Standard), SxS Pro (higher speed), and SxS Pro+ (maximum performance). All variants support UDMA-7 and feature integrated wear-leveling algorithms.

History & Development

Sony introduced SxS in 2007 concurrently with the XDCAM EX series, starting with the PMW-EX1. The system was developed in response to the limitations of tape-based workflows and the then-slow SD/CF cards. In 2010, Sony expanded the portfolio with SxS Pro cards for 4K recording. From 2019, Sony began the gradual migration to XQD and CFexpress Type B, but continues to support SxS for legacy systems. Over 50 camera models supported SxS in its heyday.

Practical Use in Film

"The Social Network" (2010) used RED cameras with SxS adapters for certain handheld sequences. Documentary filmmakers appreciate SxS for its robust construction – the cards can withstand temperatures from -25°C to +85°C. The typical workflow involves direct recording to two SxS cards (Mirror/Backup mode), followed by file transfer via USB 3.0 adapters. Disadvantages: high cost (approx. €8/GB), proprietary standard, and limited capacity for modern 4K productions.

Comparison & Alternatives

Unlike CompactFlash, SxS offers higher speeds but remains more expensive. XQD cards (Sony/Nikon standard since 2012) deliver double the transfer rates with similar robustness. CFexpress Type B is increasingly replacing SxS in new Sony cameras like the FX9. Panasonic's P2 cards were direct competitors but remained limited to Panasonic systems. Today, SxS is primarily suitable for established XDCAM workflows, while CFexpress is recommended for new acquisitions.