Absolutely fantastic information for those of us seeking to learn the why’s and how’s of these audit circuits. Thank you for waking this through, and especially for breaking down the gyrator functionality.
Man this was a sanity check for me I m going probably over thinking a tone pot for my baritone guitar and here you go you gave me everything I need. Please do more of those.
I’m a little confused. You have 62, 125, 500, 1K, and 4K bands, but you have an output low pass filter of 1.6K. Doesn’t that significantly cut the 4K band, making that one irrelevant?
It does cut, but it doesn't cut until all the cuts and boosts of the 62, 125, 500, 1K, and 4K are summed together into one signal. I cut there, because it just "starts" cutting at 1.6K, but doesn't really taper off until the 2.7K mark which is where I like my rhythm playing at. I'm not a bluesy or shreddy lead guy that plays in standard E tuning, so I don't want a lot of harshness that comes out at the tale end of my signal. Otherwise, you could make that low pass something higher, like at 3K or so. So it doesn't make it irrelevant, it's just deciding when you want to cut those frequencies. Before or after you tweak the signal.
Great video! Even though I wasn't looking for it specifically, this clarified a lot of stuff I wanted to know for different projects! I've got a question about the gyrator-circuit (starting at ~ 13:48): Since the Resistors R9 and R10 contribute to the value of the set frequency, would it be possible to replace one of them (or both) with a pot set up as variable resistor to change the responding frequency? Cheers and thanks in advance!
This would be a bit of a trick, depending on the room inside the pedal enclosure. The easiest, so long as the room requirements inside the enclosure are met, would be to add a Baxandall Tone Stack PCB circuit. There are a lot of projects out there that have perf-board designs for that. To that Baxandall, you'd need to provide it a ground source, and a signal in and out. Usually, people look at their pedal's schematic and find a resistor that is in a good spot and use it for the "audio in and out" lines. This also assumes the circuit has "a good spot", which some do not have on existing and may require a little creativity to fix that. Good examples of this are Fuzz-Face circuits.
if i wanted to add a pulsing led with the lfo in my lich king, how would i go about doing that? also if you guys made a phaser that would be awesome! cheers
Well, you can pull a resistor off the oscillator portion and pull that to your LED and that should work. However this may slightly effect your signal. If that were to happen, you'd have to use an N MOSFET, a pull down on the gate, source to ground, a resistor to drain, and that resistor to your LED and then the LED to 9V. I have two Phasers made up. One is an MXR 90 clone using matched JFETs and one using 3 OTAs.
Hello, so glad to find your channel, bcoz I want to make my own pedals and guitar amplifiers...I just have one question/problem, I made one bigger amplifier 2x12 with a lot transistors and capacitors from some old stereos, connected power, speakers, volume, bass, treble, balanse and mic jack as well...everything works fine on 6v adapter, but I DON'T KNOW WHERE TO CONNECT guitar jack on all that big circuit, pls answer me, greetings
