The stages in any project can vary, but a typical sequence will include the following.

Initiation: The initial circuit idea is developed, either designed from scratch or identified in an existing circuit design.

Concept development and background research: Various questions can help to evolve and solidify the initial idea into a concrete design. Have others built this or similar circuits? What can be learned from their experiences? What worked and what didn’t? What variations on the theme have been described? All of this is likely to mainly involve online research, and possibly reference to circuit cookbooks such as those by Penfold and others (see for example Anderton, 1992; Boscorelli, 1999; Penfold, 1992).

Procurement: A bill of materials (or BOM) is compiled based on the circuit to be built, and all the components and tools likely to be needed are assembled. A well stocked lab may provide all that is needed, but in the early days, building up supplies of useful kit and components can take some time.

Prototyping, testing, and development: It is most likely that a breadboard version of the circuit will be the logical first building phase. Based on the circuit developed over the research phase, a breadboard layout should be designed, and then building and testing can commence. Questions previously formulated can be examined, experimenting with possible circuit modifications until a final design is settled upon.

Final layout design: With the circuit finalised, a stripboard layout can be designed. Circuit building and debugging: Once a detailed design is in place, the building process is a moderately straightforward affair.

Packaging: Questions of mounting and housing a project are beyond the scope of the material covered here.

The following step by step project walk through uses as a case study the ‘Bazz Fuss’ fuzz effect circuit already encountered several times in earlier chapters. The Bazz Fuss is a circuit commonly encountered online, and often recommended as a good first project. Unfortunately, online resources are prone to move or disappear completely, as seems to be the case with the original version of this circuit. References to web sites are generally avoided in this book for this very reason, despite the fact that the internet is an invaluable source of information and ideas.

While the original Bazz Fuss appears to be long gone from the internet, many excellent examinations and modifications of this circuit can still be found, and diverging from the practice adopted in the rest of the book, some of these are highlighted below. The following online resources provide (at the time of writing) a wide range of excellent information and suggested modifications relating to this one modest circuit.

Beavis Audio Research presents the circuit in its most basic form, and directly references a now defunct original source. Some interesting modifications are also suggested (http://beavisaudio.com/beavisboard/projects/bbp_BazzFuss.pdf).

Escobedo’s Circuit Snippets is most often encountered as a collection of simple projects, each presented as a circuit diagram with no more than a paragraph or two of notes. The original source once again seems to be long gone, and the contents of the collection can vary a bit between existing reproductions. One of the most complete versions of the collection currently accessible is at http://www.diale.org/escobedo.html. This includes an interesting Bazz Fuss variant, and brief but useful notes on the suggested modifications.

home-wrecker.com provides a much more expansive examination of the circuit (http://home-wrecker.com/bazz.html). It starts with the basic version and then proceeds to examine a number of possible routes to interesting modifications, suggesting various experiments for tailoring the tone of the circuit.

tonefiend.com takes a similar approach, again evolving the original circuit, adding various modifications to make the circuit more flexible and interesting (https://www.tonefiend.com/wp-content/uploads/DIY-Club-Project-2-v02.pdf).

diystompboxes.com is one of many forums dedicated to building your own audio circuits. Forums threads can be long and rambling but often contain little gems of information. Chances are, if a circuit can be found online, then there are forum discussions ongoing into how to get the best out of it. Here is just one relating to the Bazz Fuss: https://www.diystompboxes.com/smfforum/index.php?topic=112626.0.

All of the above and many other sources besides, provide interesting ideas as to how this simple project can be expanded and experimented with, and as such provide the raw material of an excellent learning resource for anyone wishing to develop their own circuit project ideas. In this simple walk through, a bare bones version of the circuit, as shown overleaf in Learning by Doing 10.1, is taken as the starting point. Learning by Doing 17.3 (p. 302) examines the circuit in a little more detail.

Hobbyist electronics retailers such as RadioShack and Maplin can prove good sources of materials, particularly if there is a physical store nearby (in 2018 Maplin closed all its stores and went online only). These sources can however prove a little more expensive than some of the larger online electronics suppliers such as Farnell, Radionics, Mouser, and Digikey. Budget online megastores such as Aliexpress can also be useful, but exercise care with these vendors, as quality control may not be as consistent as with some other retailers. Bargains can certainly be had, but it is perhaps best to steer clear until you have a good understanding of the tradeoffs involved.

Also of particular interest are the more specialist stores. Audio specific components like guitar pickups and reverb pans are not usually to be found at the general purpose electronics suppliers. Similarly, less common components such as vacuum tubes and germanium devices require a little more searching. Some good online stores to start with (amongst many others) might be: Banzai, Reichelt, Tayda, Thomann, and Tube Amp Doctor. It can be well worth maintaining a component inventory, updated with each new purchase, showing where and when components were bought, part numbers, price, and some basic notes.

Learning by Doing 7.1 (p. 110) invites the reader to design a breadboard layout for this simple circuit, and as noted there, Appendix D offers one suggestion. The simplest possible modifications involve directly replacing components to see how different choices affect the sound of the circuit. While the version presented here starts with the original 2N3904 transistor, any NPN BJT might be tried. Most sources seem to favour a higher gain device, usually either a 2N5088 or even a Darlington part such as the MPSA13. Similarly diodes offer an easy option for a bit of variation, whether it be germanium parts, Schottky diodes, or LEDs.

Construct a few variants on breadboard, spend some time playing and listening to the results, and see what you like the sound of. Switchable and swappable parts are an option too, but perhaps keep it simple for this first project. With experiments concluded and a design for the stripboard build finalised, a stripboard layout is needed. Learning by Doing 7.2 (p. 113) addresses this stage. Once again, be sure to have a go at a layout of your own before looking at the example in Appendix D.

The arrangement of off-board components such as pots, switches, power connections, and I/O jacks should always be considered with the final mounting and packaging in mind. Fly leads must be an appropriate length; too short and the will need to be rewired, too long or mismatched and the results will be messy at best. Is a tin, wooden, or plastic box to be used? If so, holes will require drilling. Labelling and graphic design are also beyond the topics considered here, but do need to be addressed to really finish a project.

1. C. Anderton. Electronic Projects for Musicians. Amsco Publications, 1992.

2. N. Boscorelli. The Stomp Box Cookbook. Guitar Project Books, 2nd edition, 1999.

3. N. Collins. Handmade Electronic Music. Routledge, 2nd edition, 2009.

4. R. Fliegler. The Complete Guide to Guitar and Amp Maintenance. Hal Leonard, 1998.

5. M. Geier. How to Diagnose and Fix Everything Electronic. McGraw-Hill, 2011.

6. R. Ghazala. Circuit Bending: Build Your Own Alien Instruments. Wiley, 2005.

7. A. Hackmann. Electronics: Concepts, Labs, and Projects. Hal Leonard, 2014.

8. T. Linsley. Electronic Servicing and Repairs. Newnes, 3rd edition, 2000.

9. F. Mims. The Forrest Mims Engineer’s Notebook. LLH Technology Publishing, 1992.

10. F. Mims. Getting Started in Electronics. Master Publishing Inc., 2003.

11. R. Penfold. More Advanced Electronic Music Projects. Bernard Babani, 1986.

12. R. Penfold. Electronic Projects for Guitar. PC Publishing, 1992.

13. R. Penfold. Practical Electronic Musical Effects Units. Bernard Babani, 1994.