lesonmulticanal

The growing interest in the records for the 5-channel Home Cinema, Television or pure audio makes more necessary the search for a registration system 'surround' high quality, simple, reliable and immediately operational. The device 4 and 5 segments of equal width described by Michael Williams in the publications of the AES (see note), this growing interest in the audio industry. However, finding a satisfactory configuration of microphones can not ignore the purely mechanical contingencies related to the manufacture of a suitable support.

Williams is the star of such support, simple, reliable and adaptable to multiple configurations of equal segments 4 or 5 segments. The visual impact of this system has also been minimized. Now, only systems with 4 or 5 channels appear to meet the operational requirements' broadcast 'but the possibility of setting up a 7-channel system is also possible to experiment the new format, Blu-ray'.

A circular hub central allows to fix 4, 5 or 7 rays of different lengths depending on the directivity of microphones selected. At the end of these rays, there is a toggle that can receive a Schoeps microphone or series CCM (Compact Condenser Microphone) or Colette program, consisting of a preamplifier CMC and the full range of capsules.

The development of other combinations is contemplated to meet the needs of the audio industry. In fact, the ability to mount a microphone on a vertical rod is already proposed. While the star of Williams may be used alone, it is strongly recommended to add a suspension anti-vibratoins developed in collaboration with the company RYCOTE from the famous model Lyre Series InVision Broadcast '. This is the assurance that handling noise and other vibrations will be effectively mitigated. The fact that the whole system is suspended (and not each microphone) decrease considerably the resonant frequency and provides a much better filtering of the vibrations. One can choose two types of suspensions Lyre: the model is suitable for CCM INV1, and model the CMC INV4 + capsules. As well as in reporting and in the studio, the weight of the whole is often an important factor - with 5 microphones CCM, the set weighs approximately 500g and 950 g with the CMC + capsules. One can of course equip microphones with windscreens or Rycote Schoeps standards.

Note: Michael Williams presented a series of simple configurations in equal segments in an article in the AES presented at the 91 ^th Convention of the Audio Engineering Society in New York in October 1991 (AES preprint 3157). These configurations 4, 5 and 6 channels using supercardioid microphones, cardioid or Infracardioïdes. This publication was made ​​before the term "multichannel" is adopted to describe the systems for recording 5-channel configurations and standardized to 5 speakers that result. The article was updated in 2008 to the 124 ^th AES Convention in Amsterdam (AES preprint 7480) to include systems to channels 7 and 8. These and other articles by Michael Williams can be downloaded www.mmad.info .

The system is now distributed by Areitec, 4 rue Firmin Gillot, 75015 Paris France +33 1 45 30 21 23 areitec@areitec.fr

The Rays

3 sets of rays are provided to constitute a standard star to 5 channels, each set corresponding to a given directivity:

- Supercardioid (the shorter rays) for Schoeps CCM + CMC6 41 or MK 41

- Hypocardioïde (the longest rays) for Schoeps CCM21 or MK21 + CMC6

- Cardioid (rays of intermediate length) for Schoeps MK4 + CCM4 or CMC6

We can provide rays for omnidirectional microphones, but this configuration does not seem to give satisfactory results for optimal localization of sources.

The Star of Williams Standard is designed to channel 5. However the central hub can accommodate 4, 5 or 7 rays as needed. In this case, use a set of different radii for each configuration (4, 5 or 7) and for each type of directional (super-cardioid or hypocardioïde). These rays are available as accessories. The hub has colored markers to facilitate the mounting of: yellow for 4 channels, red and blue channels 5 to 7 channels. The central hub also has a slot for attaching a vertical rod to mount a microphone aditional dedicated to very low frequencies (the .1 of a 5.1 system).

Attaching Microphones ("Microphone Mounting Clip ')

It can fit two different bindings ('microphone clips') at each radius, one for the CCM and the other for the Colette series. Both have a standard thread 3/8 "to attach the appropriate media. However mounting the CCM does not authorize the radial fitting of the microphone position, and therefore the fixing been designed depending on the length of the radius, so that the membrane is correctly positioned. It is therefore important to use the media to set the CMS Schoeps CCM, whereas the CMC can be used interchangeably support Schoeps SG 20 or other equivalent fitting. It is only with the latter support that the position of the membrane can then be adjusted according to the specific configuration required. The cylinder that supports the mounting clip can rotate on the axis of radius to align the axis of the microphone with that of the Department.

Attaching the star microphone stand with swivel mount

The Star of Williams attaches to a standard foot by a standard thread of 3/8 ". If you must use an articulated support of the kind that is used in photo or video, you can return the hub and use the other thread 1/4 ".

Suspension

In general, it is preferable to use an anti-vibration suspension with the Star of Williams. The proposed suspension was developed in collaboration with the Society Rycote system and uses the "Lyre" of 'InVision1' or 'InVision4'. Depending on the total weight of the system, different flexibilities of mounting are necessary. For CCM, the model "Lyre" InVIsion1 is recommended, while for the series Colette, you should use the model "Lyre" of InVision4. You can also use an enhanced version of the Lyra InVision4.

This suspension system can also be mounted on a tripod with a standard screw thread 3/8 "or on a tripod by simply inverting the base. Support "Lyre" must then be rotated 180 ° to be aligned with the rays of the star.