Tone control / pre-amplifier with volume / treble / midrange / bass control.
Tone control block is built according to the widespread and well-established scheme.
The principle of timbre adjustment is based on the limitation of the capacitance in the NF of the operational amplifier, in connection with which, the capacitors in these circuits are audible and ceramic capacitors are significantly inferior to film capacitors in sound quality.
The main difference between this Tone control and similar circuits is the FULL refusal to use ceramic capacitors, which in turn significantly improves the sound quality.
At the output of the module, high-quality polypropylene film capacitors are installed. If at the input of your UMZCH there is a separation capacitor, then these output capacitors can and should be rejected by shorting them.
To avoid earth loops, and as a consequence of the background, the board requires a separate AC power supply from the main amplifier. In extreme cases, (the procedure requires working with a soldering iron and knowledge of the basics of radio electronics), the power of the main amplifier, if it is not higher than -35 ... 0 ... + 35V, can be applied to the legs of the filter capacitors (1000 μF 35V) with the correct polarity !!
Power supply 2x12 ... 23V AC
The module is equipped with two op-amps
NE5532 or TL072 to choose from.
For audiophiles, it is possible to equip with original ones:
2xLME49860
2xOPA2134
Includes 4 racks with bolts and nuts M2 for mounting in the housing.
In the presence of a transformer for powering the tone block