DIY Stereo Tube Amplifier Kit

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Using an amp kit is a great way to save money on equipment. You can build an amp to your own specs, or you can select a kit that emulates an iconic amp. Stereo amplifiers have two or more speakers. This configuration enables phase shifting, which is how chorus and delay effects are created. There are two methods of amplification: tube-powered amplification and solid-state, transistor-powered amplification. Tube technology is older than transistor technology, but it still remains popular due to warmth of the tone.

Source your parts. A stereo amplifier has four key components: a preamp, a power amp and two speakers of equal size. You can order a stereo tube amplifier kit online. The "Amp Maker" and "Classic Guitar Amps" websites are two examples of popular online amp kit retailers. The latter sells amp kits that emulate classic designs, such as the Fender Twin.

Set up a workshop. You'll need a sufficiently large work bench to lay out all of the components for inspection. Your workshop must also have a power supply for the soldering iron. Inspect your parts before you assemble the amplifier kit. Look out for loosefitting surface-mounted components, such as capacitors and resistors. If you spot any, melt the solder joint and reconnect them.

Read the schematic. Your schematic illustrates the layout of the circuit and the values of the components. Familiarise yourself with the key surface-mounted components.

Load the circuit board. Amp kit circuit boards typically arrive part assembled and pre-drilled. Follow the schematic and load the capacitors, resistors and potentiometers in order. Fit them to the top of the board but solder them on the underside. Once complete, test the circuit board with a volt meter. If any part of the circuit board returns a zero reading, the board is incorrectly assembled.

Mount the circuit board. Solder the circuit board to the preamp chassis. Solder the input jack to the relevant eyelet on the board. Once complete, screw down the top of the preamp chassis.

Load the preamp. The preamp sits on a shelf inside the amplifier cabinet. The front panel of the preamp must be exposed at the front of the amp. This is where the dials are located.

Install the power amp. Depending on the make and model of the amplifier kit, the power amp will either sit alongside the preamp or below it on a separate shelf. Don't wire the power amp yet.

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Fit the speakers. Screw each speaker into the struts that run horizontally alongside the top and bottom of the cabinet. Typically, each speaker will have a series of four holes that run along the circumference of the cone. This is where you screw them in.

Wire the four main components together. Solder a wire between the output terminal of the preamp and the input terminal of the power amp. Solder two wires from the power amp, one to each speaker. Load the tubes. Test the amplifier.

Enclose the amp. Screw in the back panel and attach the grille to the front.

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