Special M/S Equalizer with 5 Bands as Extension for the M/S Matrix W731.
The W785MS is a very special stereo 5-band equalizer with 4 fully parametric bands that has been designed to extent the build in equalizer of the M/S matrix and direction controller W731. The qualities of the equalizer are identical to the standard 5-band equalizer W785; however, this version comes with +/- 10 dB boost/cut range, which is better adapted to the purpose. The equalizer is a 2 channel version for use with the M/S input and output format that is available on the extension insert of the W731 M/S matrix. One of the internal channels processes the M chain, the second the S chain. The orientation of the boost/cut controls ist reversed for both channels, which result in a direct, frequency dependent base width control. Boosting a frequency will increase the base width of that particular frequency band that is determined by the settings of the frequency and q-factor control pots, while cutting reduces the base width in the same way. Since the equalizer compensates the boost in the M-chain with a corresponding cut in the S-chain, the eq setting will not result in a different frequency response as a usual equalizer does, but merely affect the base width in the particular frequency range.
Each of the 5 bands has an additional lever switch that selects the operation mode. When in the center position, the band works on both signal chains in the way described above. In the M or S position, the band is only active in the M or S chain, which results in a combination of both effects; the 'real' equalizer effect and the effect on the base width. Due to the special arrangement of the boost/cut controls, boosting results in increasing the base width in all three positions of the switch.
Appropriate use of these features results in remarkable improvements of the spatial image, that cannot be achieved with any other principle. You need to check this out yourself to get an idea what we are talking about.
As mentioned above, the W785MS is designed as extenter module for the M/S matrix and direction controller W731. It has no input and output stages and can only be used together with Matrix. The inputs and outputs are avaialble on the 25-pin D-sub of the frame. The pinning matches the pinning of the insert port of the W731. The MS Equalizer comes with the necessary special cable. Using the module with the W730 M/S Direction Controller is also possible.
Four of the five eq bands are fully parametric bell filters with independent controls for the center frequency and the q-factor. The sweep range of the center frequencies is 100 to 1. The bands LOW and MID1 with ranges from 20 Hz to 2 kHz and 40 Hz to 4 kHz allow treatment of kick drum and bass guitar with small q-factors, which result in precisely centered bass fundaments when used with the mode switches in the center position and with minus settings to reduce the base width. If the original bass signals are already located in the center of the stereo panorama, it can be of advantage to treat only the S chain.
The sweep ranges of MID2 and MID3 from 150 Hz to 15 kHz and 250 Hz to 25 kHz allow repair work with small q-factors as well as interesting base enhancements with wide q-factor settings. The high EQ can be modified from the default shelving characteristic to a very soft bell characteristic by the two switches 12 kHz and 8 kHz. These switches determine the center frequency of a weakly pronounced bell. Pressing both switches at a time shifts the center frequency to 4 kHz. Using the high band with boost settings result in attractive base enhancements that affect the width and depth of the stereo signal. Of course, care must be taken to maintain an appropriate mono compatibility with all base enhancements. Checking the signal in mono after changing any setting is absolutely necessary.
The hard-bypass switches the entire equalizer in and out. A remote line on the special cable activates the insert relays in the M/S matrix W731 when the EQ switch of the W785MS is pressed.
The M/S Equalizer is a V700 standard, 1 slot module that fits into all standard frames. There is no need to install the device right next to the W731 matrix. Since the mutual connections depend on the cable and not on internal wiring of the frame, it is also possible to install both units in different frames.