Sunday, December 29, 2013

My LM1875 Evolution

I've been quite some time away from the DIY world actually, and even decided to give up the idea of building my own sound system. Further, I bought a 2.1 system, an Edifier C3 to be precise, and decided to stop my DIY hobby. Then I started collecting FLAC files from the Internet, listening to some audiophile musics through this nice Edifier C3 which is not bad at all. But the same old nostalgic feeling came across and I started to question my listening experience with Edifier. Later, I started to check my account at and renew my password since I have long forgotten it. The rest is, you've probably guessed that

On December 29, 2013 the schematic was updated as follows:

A fellow DIYer reminded me to route the blocked DC offset to ground through 22 k resistor from entering IN(+) of the amplifier. Another fellow recommends higher value (470 uF) of NFB-shunt capacitor. A zobel of 10 ohm resistor in series with 100 nF capacitor is installed before the output capacitor (4700 uF) near the speaker terminals. Now this amp plays Deep Purple's Pictures of Home, Duran Duran's Rio and Avenged Sevenfold's This Means War very nice. Treble and bass are just enough. :-D