- Feb 16, 2008
- 21,240
- 23,634
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- John K Custom Basses
the schematic is correct. those diodes have nothing to do with a push/pull amplifier.
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GK rails in a pedal?
- Thread starter sprag
- Start date
the schematic is correct. those diodes have nothing to do with a push/pull amplifier.
Thanks.
My understanding is the diodes are used to offset the bias of the output transistors in order to reduce crossover distortion. Most of the examples I found show the signal inserted between the junction of the two diodes. But with a bit of effort, I found this video with the signal inserted to one side, similar to your circuit. The most relevant section of the video starts at 3:41.
In regards to testing numerous units, I have 2 of these, both made by @Dominic DeCosa . Both have identical properties in regards to hiss, though slightly different settings are necessary for identical tones, as with any pedal. While they do hiss, I don’t fault the pedal. It’s just my typical amp hiss. Many, many pedals raise the noise floor slightly. As someone who hates amp hiss, I’ve simply realized that I will have a minor bit of hiss at loud volumes, and have learned to live with it. My hiss seems similar to the audio/video sample posted earlier, and am inclined to believe it’s just he pedal and there are no defects present. Of course, I have no actual electronics background or anything, so what do I know?
@Dominic DeCosa - If my comments caused you to stop building these pedals, I retract them forthwith! These pedals are among my favorites. I can’t imagine not having them on my boards. They sound simply amazing.
@Dominic DeCosa - If my comments caused you to stop building these pedals, I retract them forthwith! These pedals are among my favorites. I can’t imagine not having them on my boards. They sound simply amazing.
How did it come out? Are you happy with how it sounds? I was one of the first guinea pigs for this pedal, and happened to get one that was out of spec. I'd love to try another one someday!
Ahahhhh... the locally sourced transformer!
Looks great! Clean, elegant style, and well-photographed to boot.
Sensei Tim
Commercial User
- May 11, 2016
- 181
- 787
- Disclosures
- Owner/janitor/grand poobah of Master Effects Pedals
I don't make this pedal, but I do have an 800RB preamp in a pedal that gets the rails tone.
While there is overlap between the super 800 and the gk rails pedal, they’re 2 different products. One being an 800rb preamp and the other an 800rb power amp sim
Totally. Also, let’s not forget that there has been a GK preamp clone kit (Growling Krizzly) available for years as well. If it ends up creating a product that people can use and enjoy, it’s all good!
Edit: TonyP has thrown some feelers out about asking Master Effects to combine the 800RB pre and the rails idea into one super GK pedal. Now THAT is a must buy for me!
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Sensei Tim
Commercial User
- May 11, 2016
- 181
- 787
- Disclosures
- Owner/janitor/grand poobah of Master Effects Pedals
Cabsims are so subjective anyway, it makes it hard to accommodate everyone with just one on/off button. I could see how it would be useful for some people, but I personally would just use my own IR post preamp. Can't wait!
