Let’s check the compatibitility of the two circuits that are integrated in the assembly. In this assembly, when we are at the printed circuit board vision, just by pressing the icon a ground plane will be created. If you don’t know how to make a ground plane, consult our tutorial about how to create a ground plane with Eagle. Doing this, you can manage a better shield against the buzzing. As you can see in the photo, we made a ground plane on our printed circuit board, that is, we covered the negative pole with a large quantity of copper on both sides. Since we didn’t have enough space, we had to tumble the 1.500 uF electrolytic condenser so that it doesn’t hit the lid of our turntable. That is to say, our filter (the R.I.A.A) correction actually amplifies deep frequencies and tones down the high-pitched ones.Ī photo of the assembly of our previous stereo R.I.A.A. This filter is nothing more than a curve on the following graphic. The resistors and the condenser R2, R3, C5, C6 form the filter of the R.I.A.A correction. The only requirement is that they are empowered with 15 volts. The integrated circuit can be a NE542 or a LM387, each of them will do, they are double operational low volume amplifiers. An electronic scheme is quite simple it consists of an integrated circuit and some other components. The circuit is integrated in the interior part of the turntable, and we have used its power source to empower our circuit, which consumes merely 20mA. Now we can connect the exit of our circuit to the amplifier’s auxiliary entrance. So, we rolled up our sleeves and this is the result. The problem is that our amplifier doesn’t have a turntable input, which means that it doesn’t have the R.I.A.A correction either. We suddenly had this idea since we wanted to listen to our vinyl discs from last year. Therefore, all turntables had to be made according to this correction.

This association proposed certain corrections to be made at the time of recording and reproducing vinyl discs so that their sound quality could be better.

Avalon preamp diagram