Tuesday 13 October 2020

JHS 3 Series Distortion

 


34 comments:

  1. Haha!! Youve been doing some awesome work man. Any change of the pg-14??

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    1. Oh! Forgot the PG-14. I'll give it a try....but it looks like it basically a JHS Haunting Mids V2 into a Wampler Plexi Drive style circuit?

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  2. People already traced those? Was pretty sure from the sound demos already that they're going to be rather shameless clones.

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    1. JHS posted the schematics for all of them, so there was no need to trace.

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    2. MDS, You got a source for those schematics? tried looking but cant find anything

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  3. so basically a modded turbo rat?

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  4. built this if you want to confirm! i decided to go with a J201 and Bat41's and a Led+4148 combo. its kinda weird having the reverse taper for the filter as im used to the normal one but meh, i'll get used to it, its usually set and forget for me anyways!

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    1. Thanks Andy. I'll tag it.
      If you are looking for the schematics, they are in the PedalPCB forum.
      https://forum.pedalpcb.com/threads/jhs-3-series-overdrive.4274/#post-34507

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  5. Sounds great this one! I notice they've got side A and B of the Dualist on PedalPCB. Any chance at some point? All the best.
    Ben

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    1. Would love to! But sadly there is no schematic included in the build doc (yet)...

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    2. brother, please indulge us with the JHS moonshine, thanks for all the work you do, I admire you a lot brother http://www.pedalpcb.com/docs/BootlegOD.pdf

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    3. Thanks, man.
      Will post a layout in a couple of days.

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  6. n00b question: I can't find the PF5102 except for silly money. I assume I could use J202 (the original on JHS's circuit) or something like the 2n5457, 2n5468 etc or NTE458 instead? I'm going to socket the transistor so swapping out will be easy anyway. Thanks!

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    1. It is an output buffer so it doesn't generate any gain. So J202, 2N5457, 2N5458 or J113 will work just fine as countless other J FETs.

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    2. Thanks for the really quick reply :)

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  7. I build it sounds great but a get a big increase in sound with the loud switch about a 35% jump anyone else get thi

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    1. That switch choices silicon diodes or LEDs. The LEDs has more volume that silicon diodes (and less distortion). So it should be normal.

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  8. I've had two separate goes at this with consistent flaws... something's not quite right...the sounds is very starved like there's not enough voltage or something... And the switch pops loudly.
    It's so similar to the standard rat though!

    I've made the standard rat with good results....🤔

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  9. Any help with this would be much appreciated as I'd really like it.
    Is there perhaps a wrong way to wire up the filter/switch off row j?
    I've tried linking both with two wires and also linking them in sequence... either way I get the very weak starved distortion. (Fet an IC are verified as ok)

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  10. Had another crack at this 2 years later. There's definitely an issue with it sounded gated. D3 is permanently illuminated regardless of the switch position. Any idea guys?

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    1. I looked over the schematic and all looked kosher to my bad eyes. Maybe you're misplacing something. The LEDs are placed anode to cathode in rows K and L on your build, correct?

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    2. Yeah all good. I've built it 3 times with the same results. Really gated, and starved with a poppy switch. I've built the stock rat from here (which sounds amazing)and the only difference is the 2m2 resistor after the input (and the additional clipping diodes) so weird 🤔

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    3. Could it have something to do with the pinout of the FET you're using? PedalPCB has a schematic for it if you want to look yourself. It has a typo. The 10nf is listed as 100nf.

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  11. I'm using the same fet the same way as the standard rat. I think I need to give up on rats with diode options 🤣

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    1. Don't get psyched out, it's a simple circuit. If you keep at it, you'll figure it out. I've never been big on rats but I've built many trying to understand the obsession others seem to have. I do like the 1981 and the Thorpy Warthog.

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    2. Have you tried a different JFET Ian, could be a dodgy 5102

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    3. I'm using a 2n5457, because it worked really well in my standard rat...

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  12. Ok, so this definitely isn't verified. I moved the top lug of each led to row J and it's classic glorious rat sound. Flip the switch and it's the same starved sound. I tried moving the switch 3 wire from J to L but there's no signal there.... I think I the 2 sets of diodes are clashing with eachother somehow.

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    1. Like Chris says, it ain't you, Ian. Try this: move the LEDs back to where they are on the layout, then add a cut under one of the diodes, at either K12 or K13. Right now, the LEDs are permanently in the signal path; adding the cut will but then back on *only* Lug 3 of the switch.

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  13. Okay Ian - you are not crazy - there is an error on this drawing based on the pedalpcb schematic for the Triad Distortion. However - I say this also noticing that there is no 4u7 capacitor on the input of the pedalpcb schematic like there is here, so Anders may have used a different schematic, but I think this is what needs to happen to fix the LEDs sounding starved. The 1k resistor and 4u7 cap that are coming off pin 6 need to be switched around so the the anode of the 4u7 cap is connected to pin 6, then the cathode connects to one side of the 1k resistor, then the other side of the 1k resistor goes to lug 2 of the diode select switch. The only thing that should be connecting to the diodes are lug one of the switch to the silicon ones (other side of those go to ground) and lug 3 of the switch to the LEDs (other side of those go to ground).

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    1. Actually - that second 4u7 is not on the input. On the pedalpcb schematic it goes pin2 of the IC➡️560R resistor➡️4u7 cap➡️ground - which it also does on the drawing. Sorry - I drove for 12 hours from Cedar City, Utah to Denver CO today. I'm a little fried.

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  14. Nice catch. Didn't see that.

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  15. Cut under the diode for the win! I did feel like all the diodes were engaged at once, but didn't know how to remedy it, so thank you so much 😊

    https://youtu.be/GrU2ea3sr20?si=O1Kf1WyW1Q1377dj

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