Guitar Effects Explained

[Simon Barden]

A circuit diagram would help for that fuzz, rather than just the component layouts.

I'd guess that the signal boost could be increased, so that as the input signal level drops, more of it is pushed up to clipping level. So you could try adjusting the booster gain resistor values.

[Bakersdozen]

A circuit diagram would help for that fuzz, rather than just the component layouts.

I'd guess that the signal boost could be increased, so that as the input signal level drops, more of it is pushed up to clipping level. So you could try adjusting the booster gain resistor values.

Thanks Simon. I actually stumbled upon the answer when searching for the schematic. Someone else was having same issue. I must have been using the wrong terminology when searching previously (so much to learn).

Turns out the schematic had missed a resistor in parallel with the diodes, which is obviously what this layout was copied off.

I'll give it a burl tonight.

[Joe Garfield]

I picked the Jack Orman ebook Guitar Effects Explained from Amazon today. So far I am finding it very readable. It avoids too much math, and reads like a plain English description of how effects work at the circuit level.

I highly recommend this to anyone interested in building pedals, and also to anyone who just wants to know more about the magic.

There is some assumed knowledge required to understand parts of it, but nothing so far that a quick Google search can't fix. For example, the early section on boosters says "our signal is AC coupled into the booster so the clipping takes place symmetrically". Jack doesn't explain what coupling is though, or how it leads to symmetric clipping in the gain stage. Hopefully he explains the related role of the coupling capacitor after the gain stage.

Sent from my moto g(7) using Tapatalk

Thanks, for $10 I think it's a good recommendation! I looked at the preview and enjoyed it. It does leave me with questions, but if it's giving me enough information to ask legitimate questions then it must be doing something right! I didn't really understand the part about 'direct AC coupled' but realized the point was that it's a symmetric system with no other components in the way to influence that. I think it does require at least familiarity with electronics terms, but definitely not a degree in electronics.

[DrNomis_44]

Different coloured Leds have different forward-voltages, by forward-voltage, I mean that they have different voltages where they start to turn on and start glowing, in electronics terms this forward-voltage is also called a "knee", interestingly a Led's knee is more gradual than a typical standard silicon diode's knee, a germanium diode's knee is also more gradual than a silicon diode's knee, but, there is a silicon diode called a Schottky diode, that actually has a similar knee to a germanium diode, germanium is one of the first semiconductor elements that was used to make semiconductor devices like diodes and transistors, diodes were also made from another element called Selenium too, my take on germanium is that it's a "funny" semiconductor that tends to have a "slippery" quality about it, which is due to how loosely the electrons are held in a germanium atom's valence shell, it doesn't take much energy to knock the electrons out of the valence shell, an atom's valence shell determines the electrical qualities of the atom, even the energy from heat can knock an electron from a germanium atom's valence shell, which is why germanium semiconductor parts like diodes and transistors tend to be more temperature sensitive than semiconductor parts made from silicon.

Getting back to Schottky diodes, a Schottky diode is a silicon diode that is deliberately made to have a forward-voltage similar to a germanium diode, an example of a typical Schottky diode is the BAT41, I need to order some BAT41 Schottky diodes so I can do some experimenting with them.

The forward-voltage of a germanium diode is typically about .3V, a BAT41 Schottky diode's forward-voltage is about the same, the forward-voltage of a silicon diode, like for example a 1N4148, 1N914, or 1N4001 and 1N4007, is about .6V.

Interestingly, a Blue Led's forward-voltage is about 3V or so, a Red Led's forward voltage is about 1.2V, so, you could easily create asymmetrical clipping by using a Red and a Blue Led wired-up as back-to-back clipping diodes, or, if you want asymmetrical clipping at lower voltages, you could use a BAT41 Schottky diode and a 1N4148 small signal Silicon diode as back-to-back clippers, you could even try using a BAT41 Schottky diode and a germanium small signal diode or the BE junction of a germanium transistor as back-to-back clippers too.