Dreadbox Erebus DIY kit

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Stardust
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Low output

Post by Stardust » Fri Oct 18, 2019 12:18 pm

I would like to ask for advice. I have almost no experienco in soldering, but i finished building the kit. There are some problems.

The output is extremely low. I have to open filter and dial max resonance. Even after that it is very very low (almost inaudiable). I can mix both oscilators.

Signal does not go to echo (but echo unit is working).

Can anyone recomend me what do do? I would really appreciate it. (sorry for bad english...)

MerkDak
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Re: Dreadbox Erebus DIY kit

Post by MerkDak » Thu Apr 09, 2020 1:44 pm

Oi Wigglers!

Anybody in here still read this thread? I am looking to mod my Lil Erebus, but I am a complete noob in schematics design. Would be pretty cool if somebody could help me on my way. Stuff I'd like to do:
  1. Add direct VCO output jacks (got that covered)
  2. Add VCO2 hard sync (input jack covered, but I'd rather make it a switch)
  3. FM? haven't looked into that yet. Simple mod?
  4. I'd love glide, but my guess is that that's a pretty complicated one; needs additional circuitry AND it beeds to interface correctly with the CV and Midi...
  5. I deninitely would like some additional wave forms, ideally by just adding jumper cables. I'd figure it should be possible to change VCO2 Into a triangle wave (by shorting the part with the switch). Anyone got any ideas? And what about VCO1?
  6. Another useful mod would be to add a +1/0/-1 octave switch for VCO2. But I have no idea where to start and if that'd require adding a lot of components.
I've started modding and building a case. Pictures can be found on IG , I'll keep track of successful mods in this thread.

Also, this thread about modding Lil's big brother Erebus v2 by DrMarble was useful so far.

Finally; got some cool mods you want to share, show us!

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EATyourGUITAR
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Re: Dreadbox Erebus DIY kit

Post by EATyourGUITAR » Thu Apr 09, 2020 7:53 pm

everything is pretty easy. you need to understand electronics first. you put the slew circuit in series to the CV input. the 1v offset or 2v offset on a switch, that goes into the summing node after a 100k input resistor. you add a 100k for each input. notice the 100k resistor after the tuning knob. the 100k after the cv input. you add a dc offset through a 100k to that summing node right there. if you want slew on the midi input, you have two choices. you can duplicate the slew circuit again, or you can put a mixer before the slew. whatever you prefer. you could also rewire it through the normal on the cv input jack but then you would not be able to use midi and cv input at the same time. FM is already available. you patch to the cv input on the vco. you can add jacks with attenuators no problem. put another 100K resistor into the summing node. extra waveforms are possible but that would probably go beyond simple cheap easy mods for a noob.

https://www.dreadbox-fx.com/wp-content/ ... layout.pdf
WWW.EATYOURGUITAR.COM <---- MY DIY STUFF

Philthy
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Re: Dreadbox Erebus DIY kit

Post by Philthy » Wed Sep 16, 2020 12:31 am

Hi everyone,

First post, and apologies to revive an old thread.

Long time guitar player and amp/pedal builder. Have just taken the plunge into the world of modular - well semi modular at least in the form of a Lil' Erebus kit. I have a Keystep also.

Was keen to make a desktop case for the Lil' Erebus while it finds me via post. Was hoping someone could provide me with exact measurements of the front panel. edit: and the pcb if its accessible.

Thanks in advance.

Gohan2A
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Re: Dreadbox Erebus DIY kit

Post by Gohan2A » Thu Sep 24, 2020 11:32 am

hi Philthy,

Front panel : 21,3cmx12,85cm
PCB : 21,3cmx10,9cmx approxim. 2,3cm

Philthy
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Re: Dreadbox Erebus DIY kit

Post by Philthy » Mon Sep 28, 2020 10:54 pm

thankyou very much

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Troubleshooter
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Re: Dreadbox Erebus DIY kit

Post by Troubleshooter » Tue Sep 29, 2020 4:50 am

Too bad they don't publish the mcu firmware for future troubleshooting...

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EATyourGUITAR
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Re: Dreadbox Erebus DIY kit

Post by EATyourGUITAR » Thu Oct 01, 2020 11:01 am

Troubleshooter wrote:
Tue Sep 29, 2020 4:50 am
Too bad they don't publish the mcu firmware for future troubleshooting...
from what I read on muffs, %50 or %90 of people can't figure out how to compile and flash firmware even if they have the source code given to them. having a binary blob does not help you unless you are an expert with decompiling binaries. making major changes from a binary that has been decompiled and labeled correctly is much harder than writing the code in C. probably %1 or less of muffs users can do this with a binary for Arm M4 architecture. however, if the chip is not read protected you can grab the binary in less than a second. this is enough to troubleshoot and debug but not so easy to make changes. you need to inject the debug stack into the binary and reflash it before you can even do any debugging anyway. for some people, they can fix anything without help. for others they may or may not get stuck and ask for support. support costs money. it needs to be cost averaged into the product. free source code is not really free unless you get it with no expectation of support. look at all the people talking bad about the instructions posted by mutable instruments not being clear or correct. this makes me want to never publish source code if it will become a problem. teaching someone how to do development is not the same thing as supporting a product that is defective. I don't think manufacturers should be required to teach embedded development if they don't want to. the backlash for publishing free open source software while running a business is unavoidable. it also opens the door for other companies to develop the same product without the same development costs. probably nothing is stopping you from troubleshooting the module right now. come back when you know if it is read protected or not. you can also find bugs in the bootloader that enable dumping even if it is read protected. these bugs are well documented on the internet. so do the work, tell us what you find. if you can't dump the firmware, and you need to do a repair, contact the manufacturer for a warranty claim or repair help. they may put you under NDA so they will help you but you can't leak it. that seems fair. if you want source code that you don't even need because your unit is not broken then I think that might be expecting too much.
WWW.EATYOURGUITAR.COM <---- MY DIY STUFF

eis
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Re: Dreadbox Erebus DIY kit

Post by eis » Fri Jan 15, 2021 3:58 am

Hi yall, can you please confirm or deny this behavior is normal? On my lil erebus, the envelope is _always_ hardwired to the filter, even if I plug cables into the env out or the cutoff in (then, the cutoff is just the sum of what I feed into there and the envelope).

MerkDak
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Re: Dreadbox Erebus DIY kit

Post by MerkDak » Wed Jan 20, 2021 11:13 am

eis wrote:
Fri Jan 15, 2021 3:58 am
Hi yall, can you please confirm or deny this behavior is normal? On my lil erebus, the envelope is _always_ hardwired to the filter, even if I plug cables into the env out or the cutoff in (then, the cutoff is just the sum of what I feed into there and the envelope).
I''l check later but I think you're right.

eis
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Re: Dreadbox Erebus DIY kit

Post by eis » Sun Jan 31, 2021 3:35 am

MerkDak wrote:
Wed Jan 20, 2021 11:13 am
eis wrote:
Fri Jan 15, 2021 3:58 am
Hi yall, can you please confirm or deny this behavior is normal? On my lil erebus, the envelope is _always_ hardwired to the filter, even if I plug cables into the env out or the cutoff in (then, the cutoff is just the sum of what I feed into there and the envelope).
I''l check later but I think you're right.
Quick reminder if you forgot to check :)

MerkDak
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Re: Dreadbox Erebus DIY kit

Post by MerkDak » Tue Feb 02, 2021 2:38 pm

eis wrote:
Sun Jan 31, 2021 3:35 am
MerkDak wrote:
Wed Jan 20, 2021 11:13 am
eis wrote:
Fri Jan 15, 2021 3:58 am
Hi yall, can you please confirm or deny this behavior is normal? On my lil erebus, the envelope is _always_ hardwired to the filter, even if I plug cables into the env out or the cutoff in (then, the cutoff is just the sum of what I feed into there and the envelope).
I''l check later but I think you're right.
Quick reminder if you forgot to check :)
Thx, i did.

Plugging something into cutoff does not break envelope to vcf. Only way to achieve that is setting vcf depth to 0 i guess.

eis
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Re: Dreadbox Erebus DIY kit

Post by eis » Mon Feb 22, 2021 2:31 am

MerkDak wrote:
Tue Feb 02, 2021 2:38 pm
eis wrote:
Sun Jan 31, 2021 3:35 am
MerkDak wrote:
Wed Jan 20, 2021 11:13 am
eis wrote:
Fri Jan 15, 2021 3:58 am
Hi yall, can you please confirm or deny this behavior is normal? On my lil erebus, the envelope is _always_ hardwired to the filter, even if I plug cables into the env out or the cutoff in (then, the cutoff is just the sum of what I feed into there and the envelope).
I''l check later but I think you're right.
Quick reminder if you forgot to check :)
Thx, i did.

Plugging something into cutoff does not break envelope to vcf. Only way to achieve that is setting vcf depth to 0 i guess.
Yeah, but setting the envelope depth to 0 also sets the ouput signal level to 0. Not a clever design.

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