Simple Pre-Amp with One Transistor

This is a very simple pre-amp circuit which use a transistor as a active component to boost the input signal. Its simplicity makes this circuit easy to built and inexpensive. The microphone used in this circuit is electret type which is very sensitive detecting the sound around its.

Low Noise Stereo Preamplifier based NE5533

This is the circuit diagram for low noise stereo preamplifier based on NE5533 operational amplifier. The circuit uses 2 pieces of NE5533 since there is only 2 op-amp circuits inside NE5533. This circuit is featured volume level, right/left balancing and loudness level adjustment. It will be easy to build this circuit since the components used in this circuit is not much and easy to find at electronic store.

Guitar Pre Amplifier using TL072

The following diagram is the circuit diagram of guitar pre-amplifier. The circuit built using dual op-amp circuit which is already included in IC TL072

Guitar Pre Amplifier circuit notes:

• IC pinouts are industry standard for dual op-amps. Pin#4 is -ve supply, and pin#8 is +ve supply.
• Diodes are 1N4148, 1N914 or similar.
• Op-amp supply pins must be bypassed to earth with 100nF caps (preferably ceramic) as close as possible to the op-amp itself.
• Pots should be linear for tone controls, and log for volume and master.

Guitar pre amplifier circuit source: http://projects.mestcs.com/project27b.htm

Vinyl Pre-Amplifier circuit

This is Vinyl Pre-amplifier circuit. This circuit will make your audio system have a great audio performance.

Detail explanation about this vinyl, visit this page.

Universal Pre-Amp circuit

This is the universal pre amplifier circuit diagram that can be used for common input such us microphone, cd player, tape recorder or other electronic circuit which require pre-amp.

Download the schematic in PDF format

Condenser Mic preamplifier

This is a very simple preamplifier circuit for condenser microphone. This mic preamplifier also can be used for dynamic microphone.

You can replace the BC549 with BC109C. For better audio result, use ultra low noise transistor BC650C.

14Watt Audio Amplifier + pre-amp and tone control

This is the schematic diagram of 14 watt power audio amplifier included the pre-amp circuit and tone control circuit. I think this is complete audio system, just need an input and output (speaker)... :)

Use this power supply circuit: