Introduction: What Is This and Who Is It For?

First Watt's Aleph J amplifier

This blog is meant to be a (relatively) step-by-step guide for (relatively) inexperienced hobbyists ("noobs") interested in successfully building an Aleph J stereo audio amplifier. 

The project and this blog is possible only thanks to the contributions of talented and generous folks who hang out at the DIYAudio forums. In fact, before this journey is over, you'll likely have become very, very familiar with DIYAudio, especially the Pass Labs sub-forum and the many threads devoted to the Aleph J. 

What is an Aleph J amplifier? 

Good question! The Aleph J is a low-power (25 watts into 8 ohms), single-ended, class A, solid-state, stereo amplifier dreamt up by legendary amplifier designer, Nelson Pass. Originally produced as a commercial product by First Watt, Mr. Pass subsequently invited hobbyists to build their own, contributing schematics and know-how in the DIYAudio forums. 

What makes the Aleph J special? 

The short answer is that the Aleph J is the last iteration of a family of Aleph amplifiers that have been regarded since their debut in the 1990s as sounding extremely good (see this rave Stereophile review of the Pass Labs Aleph 3). Referring to the Aleph J, Nelson Pass says "I consider it the best of the Aleph series." It's also relatively easy for a DIYer to build, as it's built around a relatively simple circuit with relatively few parts. 

For a more information, you can read First Watt's Aleph J owner's manual, as well as the review at 6moons

I've never built an amplifier before. Should I take this on? 

Maybe? Ideally, before you tackle this project, you will have had at least some introductory experience with soldering, mounting parts onto printed circuit boards, and be somewhat familiar with basic electronics concepts (resistance, impedance, AC, DC, voltage, current, etc.) and vocabulary (resistors, capacitors, heat sinks, transistors, etc.). 

For comparison, here's my prior experience: about 20 years ago, I refurbished a Dynaco ST-70 tube amplifier. About 12 years ago, I built the Amp Camp Amp (another Nelson Pass design, and a GREAT first-timer project). Last year, I built an EL84-based tube amplifier as part of a class offered by my local parks & recreation department. So I've done some soldering, but I'm hardly an electronics veteran. 

What flavor of Aleph J will you be building? 

Our goal here will be a "plain vanilla" US-voltage (120v/60hz) Aleph J, built using printed circuit boards, chassis, and transistors from DIYAudioStore. As I'm located in the U.S., my choices for parts vendors and the like will focus on sources that are convenient for U.S. builders. If you need specific advice for other territories or for more exotic Aleph J variations, you'll find lots of information on the DIYAudio.com Pass Labs subforum.

How much will this cost? 

Approximately US$800-900. That's the budget for parts, including printed circuit boards, chassis, heat sinks, transformer, back panel hardware, hookup wire, and assorted odds and ends. In addition, if you don't have them already, you will need some basic electronics tools, such as a digital multimeter, soldering station, wire cutters and strippers, and a dim bulb tester. A decent set of those tools will probably cost somewhere between US$150-250. So, roughly US$1,000, altogether, depending on what tools you already have on hand. 



Comments

  1. I am going to build a F6 but the Build Notes for it and the Universal Power Supply are too obscure for anyone who is not an electronics expert! Thanks heaps for taking the time and effort to write this blog. Its very much appreciated.

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