Designing A Guitar Tube Amp: Part 2

Defining Amp Specs

As stated in part one, reading up on the subject of tube amp building is a great place to start when you want to build something. If you use web resources, bookmark them in a folder in your browser because there will come a day when you’ll want to reference it. Sometimes I have an idea in my head, and I forget where I saw it. Having your stuff in order will help you locate something should you need it.

After you’ve become familiar with the process of building an amp, the next step is to figure out what kind of amp that you want to build. The easiest guitar amp to build is one with a single-ended output. I’ve build four of these in the last few years of which three still exist; I turned the parallel 6DG6GT into a single 6DG6GT in 2013, and I updated it in 2014.

The Specs of My Build

I’ve started a new project that will take me quite some time to complete due to the complexity of the build (in both the design and the cost). Here is where I started on this build. Every part of the project will be based on these findings. These specs may change over time given the availability of parts or feasibility of design, but this gives me a good starting point.

  • EL84 Push-Pull Class AB power amp
  • 15 to 20 watts power output
  • Fixed bias on power tubes
  • 8ohm output
  • 300V power supply
  • Single channel input
  • Single 12AX7 preamp
  • 12AX7 phase splitter
  • No effects (tremelo, reverb)

Based on this I have my starting point. Now I have to decide what I want to design first. In the next post, I’m going to start by using the EL84 datasheet to draw load lines, and find the operating point of my power amp section.

About robbie

I am an electronics enthusiest and a ham radio operator (W1RCP). I like to play with electronics. It's fun and educational. I looked forward to working in the engineering field in the future. I have a BS in Electronics Engineering Technology from DeVry University. I also have an Associate's degree in Marketing Management from Moultrie Tech, and a diploma in Electronics from MTC.