Circuits of devices and assemblies for stereo and hi-fi

Complete stereo tube amplifier with tone control and signal source selector

At the earlier as a beginner self-construction project much described stereo amplifier with only two tubes ECL86 bothered me, that with the existing high and low tone control no increase but only a reduction of the respective frequency components was possible. In addition, the balance controller left a lot to be desired and the circuit for the auricular frequency correction (loudness) could not be turned off... read more

Homemade stereo mixer amplifier for mains and car battery operation

The DIY mixer amplifier shown here has a maximum output of approx. 2x40 watts. It is suitable for 230 volt mains operation and for connection to 12 volt vehicle electrical systems. There are four mixable stereo inputs to which e.g. keyboards, outputs of stereo guitar effects devices, MP3 players or notebooks can be connected. It is therefore well suited for field days, outdoor parties and street music performances... read more

Components for building stereo or hi-fi amplifiers:

• Circuits for equalizer preamplifiers for magnetic pickups
• Stereo preamplifier circuits equipped with tone control
• Graphic nine-band equalizer with conventional LC series resonant circuits
• Transistor power amplifiers for power outputs from 15 to 120 watts

Other content related to audio and hi-fi:

• FM broadcast superheterodyne in IC technology
• Requirements for high-quality audio equipment according to the HiFi standard DIN 45500