[BUILD] God's Box 'Humpback' - 8hp Eurorack Multimode VCF

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Naenyn
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Re: [BUILD] God's Box 'Humpback' - 8hp Eurorack Multimode VCF

Post by Naenyn » Wed Jul 01, 2020 5:04 pm

Just thought I'd follow up on the transistor issue. I received my replacement transistors today and got them installed without issue. My Humpback now sounds pretty glorious. It does still do the odd square wave thing with the low pass out, max resonance, max frequency, but perhaps that is part of the design? Seems like the resonance goes so bonkers that it starts getting squashed in to a square wave.

Anyway, thanks to Thonk for getting those replacement parts sent out and to God's Box for designing such a nice filter!
-n :ninja:

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Monobass
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Re: [BUILD] God's Box 'Humpback' - 8hp Eurorack Multimode VCF

Post by Monobass » Wed Jul 01, 2020 5:08 pm

Naenyn wrote:
Wed Jul 01, 2020 5:04 pm
Just thought I'd follow up on the transistor issue. I received my replacement transistors today and got them installed without issue. My Humpback now sounds pretty glorious. It does still do the odd square wave thing with the low pass out, max resonance, max frequency, but perhaps that is part of the design? Seems like the resonance goes so bonkers that it starts getting squashed in to a square wave.

Anyway, thanks to Thonk for getting those replacement parts sent out and to God's Box for designing such a nice filter!
:sb:

Yeah the resonance can definitely be pushed into crazy places, if you want to tame the mayhem you can remove the shunt/jumper on the back.
Thonk - CLICK HERE - Modular Synth DIY + Eurorack Accessories Store

Sick Nick
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Re: [BUILD] God's Box 'Humpback' - 8hp Eurorack Multimode VCF

Post by Sick Nick » Wed Jul 15, 2020 5:25 pm

_marrs wrote:
Sun May 24, 2020 5:43 am
Hello. I just built the DIY kit of the Humpback and as lovely as it was to build and I'm pretty sure (and double checked) that my build is correct as the kit was beautifully put together for an idiot like me I seem to be having some problems. The Cutoff filter is acting more like a volume knob instead of a filter. The res knob is ok then all of a sudden brutal. The jumper pin on the rear is on.
Here are some images of my build and (hopefully a video)
Hi guys, I have the exact same problem. My Humpback sounds and behaves exactly the same. Didn't receive any email... Purchased it about a month ago on thonk.

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Re: [BUILD] God's Box 'Humpback' - 8hp Eurorack Multimode VCF

Post by Sick Nick » Wed Jul 15, 2020 5:36 pm

Jes... I cant find the bag with the batch number on it. I might have thrown it away. :/

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jonny_w
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Re: [BUILD] God's Box 'Humpback' - 8hp Eurorack Multimode VCF

Post by jonny_w » Thu Jul 16, 2020 1:50 am

I can verify the new transistors fixed the issue, my Humpback filter is now 100% operational! Big thanks to Thonk for sorting this out so quick.

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Re: [BUILD] God's Box 'Humpback' - 8hp Eurorack Multimode VCF

Post by Monobass » Thu Jul 16, 2020 3:16 am

:yay: thanks for your patience :tu:
Thonk - CLICK HERE - Modular Synth DIY + Eurorack Accessories Store

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Re: [BUILD] God's Box 'Humpback' - 8hp Eurorack Multimode VCF

Post by Sick Nick » Sat Jul 25, 2020 4:31 am

Would be nice if u would replace my parts too.

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Re: [BUILD] God's Box 'Humpback' - 8hp Eurorack Multimode VCF

Post by Monobass » Sat Jul 25, 2020 4:39 am

Hi Nick, I can't find a 'Sick Nick' in our records, what is your email address?
Thonk - CLICK HERE - Modular Synth DIY + Eurorack Accessories Store

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Re: [BUILD] God's Box 'Humpback' - 8hp Eurorack Multimode VCF

Post by Sick Nick » Sat Jul 25, 2020 4:49 am

Of course, I sent u a mail.

Thank you

Greets
Sick Nick

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Re: [BUILD] God's Box 'Humpback' - 8hp Eurorack Multimode VCF

Post by kevinlindley » Tue Sep 15, 2020 7:50 am

Hi,

Just ordered the God's Box Humpback Filter PCB and Panel as its on sale at Thonk. Had my eye on this filter for a while so the sale price forced my hand. Reading through the BoM it mentions only using the ON Semiconductor 2N3819 part, NOT the Fairchild part, which is fine till I started trying to source a ON Semiconductor part and all of the ones I can find in stock are Fairchild ones!.

So is it that there is just a different Pinout on the Fairchild 2N3819 from the ON Semiconductor 2N3819 ?, or is there something more fundamental ? If it's just a pinout change, does anyone know the correct pin order to stick a Fairchild part in place (is it just a 180 degree swap ?, or do I have to do something more "Twister Like" with the legs ?).

Any advice welcome before I get the soldering Iron out :-)

Kevin.

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Re: [BUILD] God's Box 'Humpback' - 8hp Eurorack Multimode VCF

Post by kevinlindley » Wed Sep 16, 2020 7:29 am

Re: ON Semiconductor 2N3819

So some internet digging and I think I can now answer my own question, and hopefully provide information to anyone who follows in my footsteps.

The Fairchild 2N3819 has the following Pin Outs : 1-Drain, 2-Gate, 3-Source
The ON Semiconductor 2N3819 has the following Pin Outs : 1-Source, 2-Gate, 3-Drain

Comparing the DataSheets everything else seems roughly the same.

So a 180 degree swap of the component (Fairchild 2N3819) should let me replace the ON Semiconductor 2N3819.

I'll post here if it turns out there is more to this substitution than meets the eye.

Kind Regards
Kevin.

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