Dumbloid  [traced]

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Coma
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Post by Coma »

Instead of going through 23 pages....is the Dumbloid pedal Close to the CJOD? I've built a few of those already.

thesmokingman
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Post by thesmokingman »

pretty much ... :roll:

MoonWatcher
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Post by MoonWatcher »

Coma wrote:Instead of going through 23 pages....is the Dumbloid pedal Close to the CJOD? I've built a few of those already.
I'd have to say actually no, because it doesn't really use clipping diodes like the CJOD does, even if there are other YATS similarities.

You'd need a YATS with a no clipping diode setting to have a better idea if it really is that close to CJOD.

It's also been mentioned that the Dumbloid has a really low input impedance. I wouldn't discount the effect of that so much. How often do you see a YATS like that? This is the first instance I'm aware of even if it was probably a mistake.

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Post by AlienSexGod »

mirosol wrote:Yup. The crappy decay is a feature. Which rather funnily makes not only a slight TS derivative, but a bad TS derivative.
Ok but have we 100% this....the original Dumbloid has crappy decay also not sure I heard that on various tube clips?

Is there anyone with some clone boards made up or does there need to be another run for mid 2015? I'd put in for a few. 8)

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Post by AlienSexGod »

OK I found where to order the boards (so many pages ... so little sleep OMG!)
In case someone else is looking order boards here!

https://oshpark.com/shared_projects/HOGyoUdG

If someone could link where the schematic is and provide any recommendations on the build, in one place, that would be great ! :P

casey73
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Post by casey73 »

My first post here. I stumbled on the Dumbloid/Big Bloom phenom late last year. The samples I saw on youtube sounded pretty okay. I built mine on a tonepad ts-808 board since I've built quite a few TS varients and have several unused boards. I used the tonepad schematic that had the new Dumbloid values in it. I fired it up this morning, and gotta say I"m pretty disappointed. The tone control has very little effect at all and the voicing control seems only to work from about 2 - 5 o'clock. And, it has lots of gain and distortion, but it really doesn't sound good and has what appears to be a common issue, and nasty farty decay.

So did I do something wrong or is that just the nature of the breast?

1oldsidewinder
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Post by 1oldsidewinder »

casey73 wrote:My first post here. I stumbled on the Dumbloid/Big Bloom phenom late last year. The samples I saw on youtube sounded pretty okay. I built mine on a tonepad ts-808 board since I've built quite a few TS varients and have several unused boards. I used the tonepad schematic that had the new Dumbloid values in it. I fired it up this morning, and gotta say I"m pretty disappointed. The tone control has very little effect at all and the voicing control seems only to work from about 2 - 5 o'clock. And, it has lots of gain and distortion, but it really doesn't sound good and has what appears to be a common issue, and nasty farty decay.

So did I do something wrong or is that just the nature of the breast?
If the taper of your pots is correct, I'd probably say nature of the beast. If you're interested in some lower gain "D" pedal tones, you might try cutting the gain of the first stage using something like .1uf/3k9 ohms at the HP filter. The op-amp won't be pushed as hard and it will help with the nasty decay. The second stage can then be tuned by replacing the 3mm LED with a lower vF diode like a 1N4148 or something since it will be getting hit with a lot less gain from the first stage. I've had pretty good success using this approach in my SD-1 mods but there may be a little more involved with an actual Dumbloid. It's a starting place, anyway...

indyguitarist
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Post by indyguitarist »

Coma wrote:Instead of going through 23 pages....is the Dumbloid pedal Close to the CJOD? I've built a few of those already.
sorta. looks like it's here: https://www.freestompboxes.org/download/fil ... &mode=view

peterc
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Post by peterc »

Hi all

I got a pair of the Oshpark pcbs and am really looking forward to trying this pedal out.

The component overlay on p14 of this thread does not seem to match the circuit numbering. Does anyone have a build doc for it?

Many thanks
Peter

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Post by peterc »

Managed to get it done......
Attachments
Dumbloid-Purple-BW-Web.jpg

mutante
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Post by mutante »

BB OPA2134 is correct op amp chip. Original Dumloid pedal using tantal capacitor for 22uF output coupling capacitor - it's a secret of Dumloid sound. I changed the capacitor to tantal and It works perfectly with OPA2134 chip.

When 22uF capacitor is eletrolytic capacitor, OPA2134 chip is meaningless but LM833N is awesome. I tried so many op amp chips - 2262, 5532, 1458, 275G, 627, 637,,,,,,,but LM833N is best with eletrolytic capacitor.

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plush
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Post by plush »

mutante wrote:BB OPA2134 is correct op amp chip. Original Dumloid pedal using tantal capacitor for 22uF output coupling capacitor - it's a secret of Dumloid sound. I changed the capacitor to tantal and It works perfectly with OPA2134 chip.

When 22uF capacitor is eletrolytic capacitor, OPA2134 chip is meaningless but LM833N is awesome. I tried so many op amp chips - 2262, 5532, 1458, 275G, 627, 637,,,,,,,but LM833N is best with eletrolytic capacitor.
Any explanation? Or this is purely subjective?

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