Dreadbox Erebus DIY kit

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vertflyer
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Post by vertflyer » Sun May 13, 2018 7:11 pm

I think mine is working. Question, does the saw vco turn down to silence when the LVL1 slider is all the way down? For some reason mine can’t be silenced. Just goes down to half volume.

Eta: I fixed it. The slider needs to be resoldered. Now it works perfectly.

Except the midi channel switches don’t get to the right channels. And the duo mode needs three notes before it kicks in.

But man. It sounds amazing.

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Catflap
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Post by Catflap » Mon May 14, 2018 4:22 am

Branko wrote:Do your MIDI modes work correctly?
Never use midi so have not checked. Its on the cards this evening tho. Will report back
vertflyer wrote:But man. It sounds amazing.
I turned it on and thought "Damn, I don´t remember it sounding this good". I have used an Erebus v2 many times and loved it. However, I prefer the lil Erebus. Loads of character.

thement
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Post by thement » Mon May 14, 2018 6:08 am


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autodafe
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Post by autodafe » Mon May 14, 2018 7:50 am

Thanks. I wrote to support yesterday, they said they are gonna release schematics and user manuale slater on....

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Morphology
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Post by Morphology » Mon May 14, 2018 8:28 am

thement wrote:I'll just leave this here
Excellent - many thanks. This answers lots of questions, and is going to assist lots of people with fault-finding their builds.

Morph
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autodafe
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Post by autodafe » Mon May 14, 2018 8:31 am

schematics are now published on Dreadbox website, on the Lil Erebus page. Better leave it here and download the PDF ;-)

Branko
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Post by Branko » Mon May 14, 2018 9:09 am

Multiple people with the same MIDI issue seems strange. Wonder if it is a built in problem with the ATMEGA chip.

Mattbartlett303
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Post by Mattbartlett303 » Mon May 14, 2018 9:23 am

Hi has anyone got midi working correctly?

I've finished my build and everything sounds great using an analogue sequencer, but when I try to use a midi keybord I'm only getting gate (no cv). I suspect a dodgy 4922 as I get 0v at pin 10 and pin 14 when sending midi in, but just want to check if this is a common problem before ordering a new dac.

I've also noticed that the dip switch combinations do not correspond to the midi channels listed on the back of the pcb, but I suspect that this is unrelated.

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xenosapien
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Post by xenosapien » Mon May 14, 2018 9:51 am

Haven´t really tested with MIDI too much after my initial "OK, that works." test, sorry...

I did feel like everything works as expected though, except I couldn´t get duophony to work... but I did NOT try to press THREE (3) keys down for that, haha.

I will keep an eye out for all of these points though next time I get around to play with the Erebus.
may you live in interesting times.

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Post by vertflyer » Mon May 14, 2018 12:47 pm

Mattbartlett303 wrote:Hi has anyone got midi working correctly?

I've finished my build and everything sounds great using an analogue sequencer, but when I try to use a midi keybord I'm only getting gate (no cv). I suspect a dodgy 4922 as I get 0v at pin 10 and pin 14 when sending midi in, but just want to check if this is a common problem before ordering a new dac.

I've also noticed that the dip switch combinations do not correspond to the midi channels listed on the back of the pcb, but I suspect that this is unrelated.
I built 2 units so far, and the regular midi works for both units. Only one of my units has the dip switches picking the wrong midi channel. The other one seems to be mapped to the advertised midi channels correctly.

vertflyer
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Post by vertflyer » Mon May 14, 2018 1:03 pm

Catflap wrote:
Branko wrote:Do your MIDI modes work correctly?
Never use midi so have not checked. Its on the cards this evening tho. Will report back
vertflyer wrote:But man. It sounds amazing.
I turned it on and thought "Damn, I don´t remember it sounding this good". I have used an Erebus v2 many times and loved it. However, I prefer the lil Erebus. Loads of character.
right? I too had a v2 and the pwm on this lil beast sounds huge. This is quickly becoming my favorite synth. I actually like the envelope limitations, it sort of forces the sound into quirky land.

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autodafe
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Post by autodafe » Mon May 14, 2018 3:27 pm

I recorded a quick live impro song using Mutant Drums-Hats-Claps triggered by Algorythm and going into Clouds, Braids for some Chords and Erebus for the main synth parts. Erebus is controlled with my Nektar keyboard, CVPal then sends CV/Gate to the Erebus

https://soundcloud.com/antonio-grazioli/erebus-song

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Barcode
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Post by Barcode » Mon May 14, 2018 10:21 pm

The schematic helped me find my resonance issue in like 15 minutes.... Visually everything looked fine, but there was a broken trace.

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Barcode
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Post by Barcode » Mon May 14, 2018 10:24 pm

Edit.... I'm an idiot..
You do not have the required permissions to view the files attached to this post.
Last edited by Barcode on Mon May 14, 2018 11:54 pm, edited 1 time in total.

vertflyer
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Post by vertflyer » Mon May 14, 2018 10:53 pm

Barcode wrote:While troubleshooting my issue I decided to do a small "mod", normalizing the EG out to switched jack of the cutoff. See the picture below for the connection points. FYI the connection is broken if you plug into the cutoff jack.

Image
Not sure I’m following. Isn’t the eg already normalled to the filter cutoff?

What I would want is the eg normalled to the vca. Seems like 99% of the time I want some release on the vca.

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Barcode
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Post by Barcode » Mon May 14, 2018 11:57 pm

Yeah I was wrong... It must have been an issue with the filter on my build before finding a broken trace. I disconnected the wire and all is normal.....

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Post by aabbcc » Tue May 15, 2018 4:57 am

Barcode wrote:The schematic helped me find my resonance issue in like 15 minutes.... Visually everything looked fine, but there was a broken trace.
Do you have the schematics for this? I would very much need them since I can't get mine to properly work

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JAO
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Post by JAO » Tue May 15, 2018 5:01 am

aabbcc wrote:Do you have the schematics for this? I would very much need them since I can't get mine to properly work
Scroll up for the link.

Branko
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Post by Branko » Tue May 15, 2018 9:51 am

Got an email from Dreadbox regarding my MIDI issues, re: paraphonic mode over MIDI:
"We will release a user manual this week, where this question will be answered :)


So what happens, is that the chip is set as being 2nd in a poly chain mode. To change that, when you power it up , at the 1st 5 sec that the power is on, change between unison and duo phonic mode at least 3 times.

This is done by the DIP switch no. 4 "
I haven't tried it yet but I hope it isn't necessary after each power-up.

thement
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Post by thement » Tue May 15, 2018 10:24 am

Branko wrote:Got an email from Dreadbox regarding my MIDI issues, re: paraphonic mode over MIDI:
"We will release a user manual this week, where this question will be answered :)


So what happens, is that the chip is set as being 2nd in a poly chain mode. To change that, when you power it up , at the 1st 5 sec that the power is on, change between unison and duo phonic mode at least 3 times.

This is done by the DIP switch no. 4 "
I haven't tried it yet but I hope it isn't necessary after each power-up.
Oh this is excellent news! Now it really does paraphony!
Just checked, you need to do that just the first time, it probably saves settings to atmega eeprom.
This also means, that it is polychainable! Just to solder MIDI Out on TX pin (i will maybe test this later).

In other news: spent whole day with the schematic, found out the issue was in VCA, resoldered two transistors (T5 and Q7), and now it works, yay!

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Monkizzle
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Post by Monkizzle » Tue May 15, 2018 11:30 am

Glad to read that a user manual is going to be released. I understand the "no support" statement but schematics and manual are really appreciated :yay:
My patience has a limiter, and it's a Behringer.

Mmdm
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Post by Mmdm » Tue May 15, 2018 11:51 am

I continue with my noise issue. I replaced all the tl074, lm13700 and the tl072. I checked all the resistors and caps also.
now with the schem I hope I will find the problem

vertflyer
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Post by vertflyer » Tue May 15, 2018 3:55 pm

How do you poly chain without a midi out or thru?

Secret port?

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autodafe
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Post by autodafe » Tue May 15, 2018 4:39 pm

vertflyer wrote:How do you poly chain without a midi out or thru?

Secret port?
Gate out/ CV Out?

Branko
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Post by Branko » Tue May 15, 2018 4:52 pm

Can confirm that the above instructions have fixed my issue! Hell yeah!

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