When dealing with voltage follower opamp circuits (buffer) the correct term is impedance as you're dealing with an ac signal.

Thanks...still 5 away!

They certainly can be. You could however have an op amp buffer at the input and a transistor buffer at the output. Also, you can think that the output buffer of one pedal could be the input buffer to the next pedal in the chain.

I can put it on the list. Essentially you need to measure output with no load, then with a known load and do some calcs

​@@pougnetpedalsimpedance is the term used when dealing wirh an audio (ac sine wave) and you called common collector when it's an emitter follower. I hate to sound like a troll man. But if you're going to teach people, do it properly. You play as well as you teach too. Practice more. You have irnin you to do both if you do it right. You need to learn how to apply ohms law to resistors in series and parallel then go from there. Most circuits are just using components to perform simple math. Audio is an ac sine wave which usually hovers above or below 9v depending on the phase desired in any part of a circuit. Over drive looks like a sine wave wirh flat top peaks. Flange and phase take position of the sine wave in the unit circle and manipulate it. Simple stuff bro. You have a decent following man and I'd hate to see you squander it because of laziness. Listen to more dream theater.

@@jstro-hobbytech Hey man, thanks for all the questions. I will try my best to answer them for you. The term impedance is actually correct all the time, and is independent of whether you have an AC or DC signal. Impedance is the sum of the effective resistance (resistors) and reactance (capacitors/inductors) of the components your signal passes through. In DC, the reactive components look like an open circuit (capacitors) or short circuit (inductors) so we can drop (or zero) the reactance part of the equation. This is why the term resistance is used when discussing DC. That said if you pass an AC signal through only resistors, the term resistance would still be correct. This is of course in an "ideal" sense as even resistors can have a very small reactive component in practice. Not sure, what I said in the video, but hopefully that clears things up. You are correct in regards to the common collector transistor circuit. It can also be referred to as emitter follower and sometimes also voltage follower. No matter what you call it, the important thing to remember is the input is on the base and the output is on the emitter. Knowing its characteristics like the voltage gain (1V/V, 0dB, or unity gain as you mentioned in another post - similar ways to say the same thing) is also worth wild. Series and parallel resistance/impedance is also pretty easy. Resistors in series have their values added, while those in parallel are equal to the reciprocal of the sum of reciprocal resistances. Inductance for inductors works the same, but it is opposite for capacitors. Capacitance in series sums like parallel resistance, capacitance in parallel sums like resistance in series. I recommend checking out an intro electronic book like Boylestad if you want more info. More precise to your explanation, audio signals are approximated by a summation of sine waves with varying frequencies and magnitudes. Check out Fourier Series (sums) or Fourier transforms (integral) for more information. They also don't need to hover around 9V. The 9V scenario you are referring to is likely when you have an 18v supply. You position your signal on a 9V DC bias so as to avoid signal clipping on the rails (0V and 18V). Most guitar pedals are powered using a 9V DC supply without a charge pump, so the DC bias for the signal is 4.5V (with rails being 0V and 9V). While I am discussing clipping, I should also talk overdrive, distortion, and fuzz. When a signal clips at the rails (gain is too high), or has the top/bottom clipped due to diodes in a hard clipping configuration (opposite direction diodes placed between your signal and ground), we hear it as fuzz or distortion. Massive gain, and rail clipping usually turns your sine waves into square waves and we refer to it as the fuzz effect. We usually refer to hard-clipped sine waves (they still look like a sine wave, but with their humps flattened) as distortion. Soft-clipping (where we put the opposite direction diodes in a feedback loop of say…an op-amp) doesn't necessarily clip the signal, but distorts it into something like a "soft" sawtooth wave and is usually referred to as overdrive. Of course these are all subjective. A light distortion could be referred to as an overdrive by some manufacturers, similarly with a light overdrive could be called a boost. There are also different methods of employing diode clipping (ex. asymmetrical clipping). Flangers and chorus pedals are slightly different than the phase effect. Flangers and chorus involve mixing your input signal with a time delayed copy or copies of itself (time domain shift). Flangers have a shorter delay than chorus pedals. The phase effect involves shifting the phase (frequency domain shift) of the input signal (usually by way of an all-pass filter). Now a time delay in the time domain is equivalent to a phase shift in the frequency domain, but the effect is noticeably different when applied to an audio signal with various frequencies. This is because flangers and chorus effects shift all parts (or sines) equally, but a phase effect affects each part (or sine) by a different amount. Lastly, you asked about my scope in another post. When choosing an oscilloscope, specifically for audio signal troubleshooting, you should be aware of a few things. First you should ensure it can sample at the required frequency. This is greater than twice the frequency of your highest expected frequency (~20kHz for audio) in your signal. This is called your Nyquist frequency. Having one output (for test signals) and one input (to probe at different locations in your circuit) would be considered essential as well. Lastly, I always like to have FFT (Fast Fourier Transform) on my scopes so I can review the frequency response of my circuit. Luckily, most $50 scopes can do all this. It's nice to have a $500 or $2000 scope for a bigger screen, higher sampling rate and more inputs/functionality (Tektronix makes some nice ones), but it is not necessary for most simple audio triage. Thanks again for the engagement! I'll keep practicing my guitar as well, but I don't envision any stages in my future :)

My guess is not. Usually fuzzes are ok with no buffer leading into it. Also, I don't think the gain would decrease, maybe you mean the level? Octave ups can have some perceived volume drop because they remove lower frequencies. My advice would be to flip the two in the chain anyway. Fuzz>Octave is probably the most common path. Other than that...maybe a boost or equalizer in between?

Likely, but best thing to do is look at the schematic. Likely an opamp or bjt input buffer