The CARTEC EQ-Pre-2A is a high quality transformer-based stereo discrete Op-amp Microphone/Line Preamplifier with full 'Pultec' type EQ, Mid/Side encoding or decoding, and and AUX
The circuit is identical to our Pre-Q5, but with the addition of fully stepped front panel controls for the High/Low frequency boost and attenuation controls. The Line level switch allows all of the features to be used both during tracking and mixing so that you could send pre-recorded sounds to the EQ section and use it as a fully featured perfectly balanced stereo 'pultec' equalizer with the ability to have it's settings recalled exactly.
The Mid/Side selector switch will perform the conversion at the output, so for instance, if using M/S mic technique the signals may be boosted, equalized, and phase inverted separately. It will then output Left and Right signals from the rear XLRs to then chain into another unit for normal Left/Right processing or to save being processed later in a digital workstation. On ther other hand, a Left/Right signal can be fed into the unit, converted, and then fed into a stereo compressor to allow it to be used on the Mid/Side signals separately.
The 'AUX send blend' feature is a third XLR output connector on the rear, and central potentiometer on the front panel (The only control to not be a switch). In its central '12 O'clock' position, this will output an even blend of both channels, and turning it in either direction will proportionately increase/decrease the level of that channel. This could be used for any number of applications, including summing a balance of two microphones on a source such as guitar amps.. between a close and room microphone..
This blend is taken from separate winding on both channels output transformers, which means no extra buffers and very minimal interference with the normal outputs which can still be recorded independantly. This is unaffected by the use of the Mid/Side switching, so if you wish to convert a mid/side microphone setup to record a Left/Right output signal, then by turning the AUX control all the way to the channel with the 'Side' microphone input.. this signal can be recorded and used at a later date to manipulate the stereo width of the recording, allowing you to work quickly and make deciscions, but also provide the option of flexibility if required.
This could be applied to anything. For instance, the same Middle, or Side signal (Or a blend) could be sent to the input of a reverb to only affect which you choose.