[pcb+panel] ssm2044 filter for eurorack

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Rafaelxyz
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Post by Rafaelxyz » Mon Aug 28, 2017 4:39 am

Il take a wooden panel + pcb + chip

Let me know how to proceed.

TimoRozendal
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SSI2144 Resonance kludge

Post by TimoRozendal » Fri Sep 08, 2017 2:22 am

If you are using the SSI2144 and you are not satisfied with the resonance control you can take a look at the following (some users report that it works without issue).

Try to add negative cv offset to the cv resonance input and see in combination with the T3 setting if this gives you a better resonance range.

If it does, please measure the negative cv offset which works best (in my case it was -2v). This offset can be hardwired in the module by adding an extra resistor.

Then determine the resistor value with the following formula:

-12/(V/47)= resistance in kOhm (where V is the offset in volts)

in my case this resulted in value of 281k that I included in the build with a 280k resistor in the following way:

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kreeper_6
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Post by kreeper_6 » Sun Oct 22, 2017 3:32 pm

I've been having the SSI2144 problem and will try this fix. The data sheet looks to have a different Q control setup though in my Polysix it doesn't seem to have this issue with 2144 but I haven't tested much.

The data sheet says the Q circuit is improved but if it ain't broke...

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synthcube
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Post by synthcube » Thu Sep 13, 2018 1:55 pm

we are VERY PLEASED to say that we have added timo rozendal to the webstore-- it certainly took us longer than we wanted (our fault, not timos!!) but we are delighted to have these modules available now!

thanks timo!!

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diode_destroyer
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Post by diode_destroyer » Mon Nov 05, 2018 10:05 pm

Just built one up from modularaddict. Nice. Had to change R15 and R15b from the provided 47k to 33k to get more range from Freq knob, and had to change R8 from 100k to 108.2k (added a 8.2k in series) so that I could get it tuned up for 1v/oct tracking (I used a vintage 2044 chip from switchedonaustin.com). I wonder why the caps were chosen like in the old 2044 datasheet example and not like the values used in the korg monopoly or polysix? What do these cap values affect?

TinyTrucks
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R15/b value

Post by TinyTrucks » Sun Nov 25, 2018 7:24 pm

Would 39k be okay in the r15/r15b? I don't happen to have any 33k laying around. oh yeah, and, I'm pretty sure this is my first post on here.

-Tiny

nervousapps
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BUILD FAILED... NEED HELP

Post by nervousapps » Mon May 20, 2019 3:01 pm

Hi,

I just bought a kit from Synthcube, build it and when I put the module under power with a simple square wave as input, nothing happen on the output.

I reviewed the board and saw that I've put the tempco in R17 so I desoldered it and put it in the right place, re-tested and nothing new.

I measured the voltage on several pins of the IC's (see photo below)

Image

The tempco is disconnected because I tried with R17 1K resistor but the values are the same with the tempco and without R17 (it is 28.8V instead of 29.4V)

I had only one header from the kit for connecting the boards so I just put some connectors on the other side as I had not the female header (see photo below)

Please tell me if I'm wrong on something, I can't find it out...

Image

:goo: :goo: :goo: :goo: :goo: :goo: :goo: :goo: :goo: :goo:

TimoRozendal
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Post by TimoRozendal » Mon Sep 23, 2019 1:53 am

hi nervousapps,
I am sorry to hear about the trouble you have. I didn't realise that Synthcube sells kits for this.

Are you saying it does nothing at all? with gain to the max and frequency to the max?
So you measured the power voltages on all three ic's?

Btw, do you have a scope?

The ssi adapter they use is a bit wider than what I sell, does it make proper contact? Did you solder it yourself? a small bridge can already make it stop working entirely.

The 820pf surprises me, it looks like a multilayer ceramic or is it mica? mica or poly is fine, ceramic isn't.
Can you doublecheck the value?

nervousapps
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Post by nervousapps » Sun Oct 06, 2019 1:17 pm

Hi Timo,

Thanks for the response, I bought another ssi2144 with adaptor from Synthcube, did a proper installation (I think the contacts were not correct, now they are).

But the module does nothing at all.

I have measured the tensions on the ICs, I have :

- +12V on pin 16, and on pin 8 of both TL072
- -12V on pin 9, and on pin 4 of both TL072
- BUT +9.45V on pin 13 of ssi2144 !!!

I don't know what kind of capacitor it is but it is the one from the Synthcube kit so I think it is the right one.

I have put 5V in Q cv and res set to max and obtain these graphs (I think it is not self oscillating) :

Image


Image

TimoRozendal
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Post by TimoRozendal » Wed Oct 16, 2019 2:47 am

hi nervousapps,
pin 13 is the cutoff pin, so that value can be ok
What are the values on pin 16 and 9?
Can you scope/record the signal on pin 1 (input) and pin 3 (output).
Timo

nervousapps
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Post by nervousapps » Mon Oct 21, 2019 1:34 am

Hi Timo,

I have +12V on pin 16 and -12V on pin 9.

Nothing on the two other pins.

:bang:

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GuitarBuilder
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Stay away from Synthcube Kit!

Post by GuitarBuilder » Fri Nov 01, 2019 9:49 pm

You know a manufacturer has an issue when you can't leave a negative review on their website - the Synthcube kit is full of issues, ranging from missing parts to no instructions and outright dumb mistakes. Their SSI2144 adapter PCB doesn't even fit a 16-pin DIP pattern - who decided that was OK? I'm speechless!

Note to Timo: your board design could use improvement. It's too easy to hook things up backwards or upside down with two 8-pin headers on both sides. Make them different! Also, having the silkscreens on the wrong side of the PCB doesn't help matters. Put those where you want folks to solder the headers!

nervousapps
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Post by nervousapps » Mon Nov 11, 2019 6:44 am

The kit for that module was not complete and it does not work but I have bought the x0x kit and had no issues.

I will request a refill to synthcube, wait & see....

Vinc3nzo
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Re: [pcb+panel] ssm2044 filter for eurorack

Post by Vinc3nzo » Fri Mar 20, 2020 5:55 pm

Hello Timo,

I Want to buy your module with Wood, where to buy?

Thank You Advance.
Vincenzo.

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humax5600
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Re: [pcb+panel] ssm2044 filter for eurorack

Post by humax5600 » Tue Mar 24, 2020 4:06 am

Many shops in the UK and in Germany stop their delivery

for example seen at : https://www.thonk.co.uk/
23rd March 2020 - Based on the latest advice from the UK government we have decided to stop taking new orders for a period of up to three weeks due to the Coronavirus Pandemic.

But eventually here : https://modularaddict.com/manufacturer/timo-rozendal

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