EarthQuaker Devices - Bellows [traced]
Someone has already picked up one of these or has some information. I liked the fuzz mix of this pedal, but I do not find any information about this circuit online. Just a picture of him that does not say much.
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- EarthQuaker Devices - Bellows component side
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- andregarcia57
- Cap Cooler
great sound....
- jrfox92
- Breadboard Brother
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Electro-Harmonix Big Muff Pi V5
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Boss DS-1 Synth Circuit Bend - Location: Akron, Ohio
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- Silver Blues
- Breadboard Brother
That's exactly what I said in the thread on Tagboard about this I'd love an explanation for this as well.roseblood11 wrote:How does Q1 work here? Looks strange...
- jrfox92
- Breadboard Brother
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Electro-Harmonix Big Muff Pi V5
Skreddy Lunar Module
Colorsound Overdriver
Electro-Harmonix Big Muff Pi Multi-Diode and Feedback Mod
Electro-Harmonix Holy Grail Room Reverb and Reverb Length Mod
Boss DS-1 Synth Circuit Bend - Location: Akron, Ohio
- Has thanked: 3 times
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This is kind of a wild guess since I haven't really studied fets, but it looks like it might be acting like a noise gate?
I'm basing that guess off of this article which states:
I haven't built the circuit, so I don't know how it acts, but, like I said, that's my guess.
I'm basing that guess off of this article which states:
The drain's connected to signal input while the gate is connected to the output of the BJT. So, if the signal isn't loud enough, then no sound should pass?If you leave the Gate (G) of a JFET open, the Drain (D) and Source (S) will pass signal through, as the switch is connected. If you pull the Gate to a voltage less than the Source, the JFET will no longer pass audio signal.
I haven't built the circuit, so I don't know how it acts, but, like I said, that's my guess.
- Groovenut
- Resistor Ronker
I believe Q1 is functioning as a clipper, swithing on/off, clipping the negative half of the wave form in response to the signal it's recieving at it's gate from the output of the Darlington collector. The fet source is biased roughly 300mV lower than the gate, which is biased by the voltage at the Darlington collector.
My 2 cents worth....
My 2 cents worth....
- Manfred
- Tube Twister
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I made a simuation of this circuit.
I made a short between drain and source and nothing happens the output shows the same signal as before with different input levels.
Now I am confused of that, who could try it with the real circuit?
I made a short between drain and source and nothing happens the output shows the same signal as before with different input levels.
Now I am confused of that, who could try it with the real circuit?
- Groovenut
- Resistor Ronker
Keep in mind that you will have a very high resistance between the gate and the source (roughly 1M depending on the fet and the gate leakage), this is what biases the Darlington. IMOManfred wrote:I made a simuation of this circuit.
I made a short between drain and source and nothing happens the output shows the same signal as before with different input levels.
Now I am confused of that, who could try it with the real circuit?
- Manfred
- Tube Twister
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The JFET acts like a diode.
The gate-source voltage is allways positive and therefore the channel resitance is very low.
That explains why the short between gate and source has not affects nothing.
I removed the JFET in the simulation circuit, connected the base and the 10kOhms resistor,
added a small-signal-diode between base and collector, and the circuit works in the same manner.
What a supprise.
The gate-source voltage is allways positive and therefore the channel resitance is very low.
That explains why the short between gate and source has not affects nothing.
I removed the JFET in the simulation circuit, connected the base and the 10kOhms resistor,
added a small-signal-diode between base and collector, and the circuit works in the same manner.
What a supprise.
- Silver Blues
- Breadboard Brother
Oh so it's kind of like a Bazz Fuss type thing but with a JFET? Interesting...