Passive circuits

[Blurillaz]

Show me some interesting ones.

[comtrails70]

[smallsnd/bigsnd]

http://thermionic.info/

see below:
James, E. J. "Simple Tone Control Circuit: Bass and Treble, Cut and Lift," Wireless World, February 1948, p. 48-50 (PDF, 176K)

[raginreggie]

http://cavepassivepedals.com.au/index.html

[eatyourguitar]

http://thermionic.info/

see below:
James, E. J. "Simple Tone Control Circuit: Bass and Treble, Cut and Lift," Wireless World, February 1948, p. 48-50 (PDF, 176K)

this could fit in a hammond 1590lb. possibly a dual gang pot for the fancy one knob tone control. squarewave parade did a passive distortion pedal in a 1590lb. not sure whats in it but its probably diodes. stew mac is selling a guitar mod called black ice. its just two diodes repackaged unicorn poop. that other link is just crazy. 6 knobs, description says that it makes it louder but its passive WTF?

[McSpunckle]

One time I put schottky diodes between my bass' tone knob and ground, so the high end gets clipped instead of just reduced. Gives the bass a nice growl without any extra effects, but it just isn't as cool as a good overdrive pedal.

[multi_s]

this should work passive, optimistic 'octave' circuit.

go here http://www.falstad.com/circuit/

and import

Code: Select all

$ 1 5.0E-6 10.20027730826997 50 5.0 50
169 288 144 384 144 0 4.0 3.0 -0.008627933599177386 -5.21772295508649E-19 0.00527489023757195
v 144 144 144 208 0 1 100.0 5.0 0.0 0.0 0.5
w 144 208 288 208 0
g 384 176 416 176 0
d 384 144 448 144 1 0.805904783
d 384 208 448 208 1 0.805904783
r 512 176 512 272 0 1000.0
w 448 144 512 176 0
w 448 208 512 176 0
g 512 272 512 320 0
w 144 144 288 144 0
x 515 121 578 127 0 24 youve
x 537 169 584 177 0 35 got
x 547 239 611 246 0 30 male
o 1 32 0 35 5.0 0.025 0 -1
o 8 32 0 35 10.0 0.0125 1 -1

...description says that it makes it louder but its passive WTF?

transformers or resonant circuits could give voltage boosts (passive). transformers 'transform' energy. a perfect transformer has power out = power in. Power = Voltage * Current. So given a signal on the primary side, the secondary side will have the same energy, but maybe in a transformed state. For example say input = 1 V @ 1 A = 1 Watt. Depending on the turns ratio you can rig it so you might get 10V @ .1A = 1 Watt. Guitar amps act as voltage amplifiers and the inputs are usually fairly high impedance. So basically it just takes into account the Voltage of the incoming signal and not the current. End result is a 'passive' boost.

[eatyourguitar]

yeah I was thinking about the example with the transformer but you just confirmed it to be true. im still learning. its the opposite of the impedance up pedal im building. the problem with that pedal is the huge drop in volume its something like 60:1. I havent tried it yet, its all theory. I'm getting Off topic sorry.

resonators, I never actualy used them maybe I should put a couple resonators before some diodes. that would be badass

[fuzz/volume-full]

you could try to use the transormer idea at the very end of the circuit but if the volume drop is hugh you'd need a pretty big *gets out physics book* secondry coil? and small primary coil, i dunno if i got the order right there.
also if a passive circuit was made it wouldn't nessaserly need input and output caps as there's no dc current right?

[aussy]

squarewave parade had some passive thingamabobs
a distortion and a ring mod if I recall correctly