SoundField Announces New Digital Surround Products
Following the commercial success of their DSF-2 digital broadcast microphone system launched last year, SoundField have announced two new digital products, the DSF-1, a surround-capable digital microphone system aimed at the discerning concert venue broadcast and recording markets, ideal for capturing classical performances in high-quality surround, and the DSF-3, a digital surround processor for the DSF-2 and the new DSF-1. Both products build on the technology underlying the DSF-2, SoundField's first digital microphone system, the design of which took over half a decade.
The DSF-2 has proved to be a great success; a perfect example of a purpose-designed product that fulfils an urgent commercial need at just the right time. SoundField's unique microphone technology, which was first pioneered during the 1970s and 80s using analogue electronics, allows the space around a single, specially-designed microphone to be captured in three dimensions and reproduced in a variety of formats simultaneously, including mono, stereo and 5.1 surround. At the turn of the Millennium, SoundField recognised that their technology would be of great interest to the broadcast industry once a standard multi-channel surround-sound audio format had been determined to accompany high-definition video transmission. In 2001, the company thus began development of updated, all-digital versions of their existing analogue technology aimed specifically at the broadcast market. This foresight ensured that the product was ready in time for the launch of the first regular HD transmissions in Europe just over five years later. The DSF-2 was eagerly picked up by Host Broadcast Services, the company responsible for the coverage of the Soccer World Cup, when they took the decision to cover the 2006 Cup matches in high definition with 5.1 surround sound. Shortly after that, European satellite broadcaster Sky made the DSF-2 one of the standard pieces of equipment for their new HD sports transmissions, where it was subsequently used on golf, cricket and UK Premier League soccer coverage. DSF-2 systems were permanently installed in the grounds of many UK premier league football clubs, positioned high up in the eaves to capture as much stadium ambience in surround as possible.
But the original SoundField microphone was envisaged as a music recording system, and it was inevitable that once the DSF-2 was a success, SoundField would adapt the design to produce a version optimised for music recording. At the same time, an all-digital processor was needed to convert the signals captured by the DSF-2 into multi-channel 5.1 surround sound for broadcast without first passing through the analogue domain. The DSF-1 microphone system and the DSF-3 processor are the respective results of these latest design efforts.
The DSF-3
[Download preliminary data sheet]
All SoundField microphone systems consist of a single multi-capsule microphone head and a hardware or software decoder unit which converts the microphone signal into a four-channel, phase-coherent signal. Known as the SoundField B-format, this signal is what really sets SoundField mics apart from other surround-capable systems. With the right proprietary decoder, SoundField B-format signals may be further decoded into any existing mono or multi-channel sound format, including stereo, M&S, and 5.1, simultaneously if required, and with perfect phase coherence. During this decoding process, which can take place long after the original event if the four-channel B-format signal is recorded to a multi-channel storage device, the audio may be post-processed to create the effect of the microphone being rotated, moved, inverted or having its pickup pattern changed, all without physically handling the mic and merely by turning controls on the decoder. Although SoundField have offered B-format decoders with this degree of flexibility for some years, the DSF-3 is the first such all-digital unit, making it the perfect companion for the DSF-2 or the new DSF-1 digital microphone systems.
A 1U, 19-inch rack hardware processor with an all-digital signal path, the DSF-3 allows decoding of SoundField microphone or B-format signals to digital 5.1 surround or stereo audio (or both simultaneously) at any sample rate. Five-segment LED displays on the left side of the front panel act as input level meters, and each 5.1 channel's output level control has separate green 'signal present' and red Clip LEDs for further peace of mind. Controls on the front panel of the DSF-3 allow a degree of freedom to alter the audio being decoded that only a SoundField system can offer: there are separate output level controls for each of the six channels in the 5.1 signal (Left, Centre, Right, Left Surround, Right Surround and the LFE sub-bass channel), and further rotary switches and buttons allow users to alter the virtual pickup pattern and orientation of the microphone without physically handling it. The perceived front and rear width of the 5.1 pickup pattern may be continuously altered with two more rotary controls, and a Focus control allows the user to vary the localisation characteristics of the 3D soundfield. The entire 5.1 soundfield can even be rotated through 360 degrees by means of a rotary encoder with a live front-panel readout in degrees. This last control also affects the independent stereo soundfield, for which separate front-panel controls are offered to adjust the stereo polar patterns and perceived stereo width.
Separate rear-panel outputs are provided for broadcasters for each of the five main channels and the sub-bass channel in AES3 format on 75Ω BNC connectors, and the B-format inputs to the decoder are on the same connectors. An additional rear-panel BNC provides the separate Left/Right Stereo output, which can also be used for Mid & Side signals. The six surround channels and the independent stereo channels are simultaneously sent out via a single digital ADAT lightpipe connector for those users with compatible equipment. Word clock inputs and outputs, and a USB port for software upgrades complete the rear panel. The release of the DSF-3 completes an all-digital SoundField surround sound production chain, and, together with a DSF-2 microphone, provides a simple means of creating surround sound from a single microphone for broadcast.
The DSF-1
[Download preliminary data sheet]
The DFS-1 system, which comprises a SoundField microphone and hardware digital control unit, benefits from much of the techniques employed in the established DSF-2 system, but with various changes to reshape it for the performance broadcast and recording markets. Thus the output signals are all 110Ω AES-EBU on XLRs, the digital format more common in the recording and concert broadcast markets, instead of the DSF-2's BNC connectors. In addition to standard 48/96/192kHz sample rates, the DSF-1 can also handle audio at the CD mastering standard of 44.1kHz, as well as 88.2kHz and 176.4kHz. Both word clock input and output are provided as standard. The DSF-1 also offers all of the features of the established DSF-2, including the ability to change the pickup pattern, output the results in mono, stereo, Mid & Side or surround sound, and to rotate and invert the mic without physically handling it. The DSF-1 is perfect for capturing performances by artists of international standing in world-class concert venues, whether for broadcast or release on disc.
