Twin Function Equaliser
A simple box of tricks that offers both 31 band mono and 15 band stereo operation at a very reasonable price.
Equalisers of one form or another are necessary pieces of studio equipment. They can be used correctively - to return a sound to its previous state after it has been undesirably altered by the audio chain, or creatively - to change and enhance the character of a sound.
One useful advantage of graphic EQ is its ability to give an instant visual picture of how and where it is affecting the sound. It can be thought of as a row of anything from 5 to over 30 faders each acting on its own range of frequencies from 20Hz to 20kHz. The greater the number of faders, the finer the frequency tuning and it can be seen at a glance which areas have been boosted or cut, by their position.
One of the disadvantages of graphic equalisers is the amount of physical space they can take up coupled with the fact that only a fraction of its ability is being utilised at any one time. Japanese manufacturers Cutec have come up with an ingenious idea that, to some extent, puts paid to these disadvantages by offering one 31 band mono and one 15 band stereo graphic in one box and only asking you to pay for one set of hardware.
Most of the 19" 2U front panel of the DE2310 is taken up by a row of 32 sliding pots. In mono mode, each of these covers one third of an octave frequency range from 20Hz up to 20kHz (ie. 20, 25, 31.5, 40 etc) with the final slider controlling the overall gain level from -15 to +15 dB. In stereo mode the sliders are used as two sets of 16. The first 15 of each set still controls the audio range but this time in two thirds of an octave bandwidths, with the sixteenth slider in each case independently controlling the overall level of each channel. This dual function capability ol the controls is achieved by a system known as multiplexing, which is basically a way of sending more than one signal through a single wire.
On exposing the innards of the unit, it was gratifying to see that there was actually something inside this graphic equaliser. More of this type of equipment than I care to remember seems to contain a power supply and a large quantity of air! Apart from the power supply this unit consists of a very neatly laid out EQ and level PCB with a smaller double-sided PCB mounted on top. This top board is liberally strewn with CMOS chips and it is this which facilitates the tricky twin functioning.
All the ins and outs for the device are provided on the rear panel as is standard for rack-mounting studio gear. Both phono and standard ¼" jack sockets are provided for channel 1 and 2 inputs and outputs. These are wired in parallel to allow their use in any combination. This is useful for those people who have standardised their studio to one connector format or the other and invariably find that the next piece of equipment they buy uses only the other type of connector. An XLR socket is also provided for channel 2 input and output. Although this channel is the one most likely to be in use as it also provides the input and output for mono 31 band operation, I do not quite see the reasoning behind the provision of an XLR for one channel only.
The 32 sliders on the front panel operate with an adequately smooth and positive feel. As well as a centre detent at the 0dB position, they also have detents at every 3dB point between -15 and +15 dB. This can slightly reduce the ease with which the sliders can be returned to zero, but is an added advantage in selecting any frequently used setting. Level of boost and cut are not, fortunately, limited purely to these 3dB increments and intermediate settings are quite possible. The 2U high front panel permits a larger physical distance over which the sliders can be moved - preferable to a tiny 1U high panel.
31 band mono or 15 band stereo operation is selected via a rectangular pushbutton to the right of the filter switches. When operating in mono, the channel 2 inputs are used and any input to channel 1 is switched out. The frequency indications for mono operation are given above the sliders and those for stereo are given below. This system works perfectly well once you become accustomed to it. The slight drawback it does have is the lack of physical width separation between the two channels in stereo mode, however, if they were separated this would make it a bit odd during mono use.
Beside the mono/stereo switch is the EQ bypass and a green LED situated above this lights up when the equaliser is out of circuit. The bypass switch is very useful during the setting up of the EQ to show, in direct A/B comparison, how the sound is being affected. Unfortunately, a faint audible click is produced by this button. During setting up this is not really a problem and if it is ever required during performance it is not really loud enough to be intrusive. Finally, the mains on/off push switch with associated red LED is situated on the far right of the front panel.
In practical tests the Cutec EQ proved efficient and easy to use. It operates quietly at all normal line levels although I would like to have seen a couple of peak LEDs just to give a positive indication of how hard it can safely be driven. I also tested it driven directly from a guitar pickup. Although not designed for use in this fashion you can get by with it at a pinch, if ever necessary, and this is a fair indication of a low noise floor. Exactly what the manufacturer's noise specifications are I don't know as a book of words has yet to be produced. Suffice to say the frequency markings are accurate enough for efficient use and plenty of boost and cut is available for the unit to function well in any normal graphic equaliser application.
The area most attractive to prospective buyers of the Cutec must be its dual role as a 15 band stereo graphic and a highly selective 31 band mono graphic. To the budget and space conscious studio owner, the unit can offer very precise tailoring of sound as it goes onto tape coupled with effective correction in stereo as it comes off tape during the mixdown process.
It can also provide greater control for recordists struggling with limited EQ on their mixing desks whilst offering still greater freedom and flexibility to those that aren't.
This is a very capable graphic equaliser in both of its modes. It is well designed, inside and out, right down to the dust-covers on its sliders and the signs are that it should give years of reliable service - something we can't really test for ourselves, unfortunately.
At £242 including VAT you would have to go a long way to find this equaliser's equal.
For further details contact: MTR, (Contact Details).
Review by Martin Sheehan
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