[pcb+panel] ssm2044 filter for eurorack

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modularaddict
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Post by modularaddict » Sat Jan 09, 2016 11:36 am

For anyone interested - we've also got these in stock in the US at modularaddict!

SSM-2044 Filter

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antf4rm
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Post by antf4rm » Tue Jan 12, 2016 1:50 am

modularaddict wrote:For anyone interested - we've also got these in stock in the US at modularaddict!

SSM-2044 Filter
This would be a good option if there chips available as well.

Anyone have a reliable source for these?

TimoRozendal
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Post by TimoRozendal » Tue Jan 12, 2016 3:46 am

antf4rm wrote:
modularaddict wrote:For anyone interested - we've also got these in stock in the US at modularaddict!

SSM-2044 Filter
This would be a good option if there chips available as well.

Anyone have a reliable source for these?
I already have your chip here... just waiting for the pcbs and panels to come in

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jackmattson
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Post by jackmattson » Tue Jan 12, 2016 6:20 am

Can you keyboard track this one? I guess the FM is linear and the V/Oct has no attenuation? So need outside attenuation from the pitch.

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Post by TimoRozendal » Tue Jan 12, 2016 6:32 am

jackmattson wrote:Can you keyboard track this one? I guess the FM is linear and the V/Oct has no attenuation? So need outside attenuation from the pitch.
a little :-)
the fm and v/oct are both exponential
See fonik's original documentation for calibration procedure, there he also mentions

"First and the foremost this is an VCF, not an VCO.
Therefore expect this filter to stay in tune for not
more than about 3 octaves."


and... the mods I propose in the build doc to increase your frequency range might introduce an issue to get a proper v/oct response

btw, I use max for live with a custom calibration and a dc coupled interface to get a much larger range

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jackmattson
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Post by jackmattson » Tue Jan 12, 2016 7:08 am

TimoRozendal wrote: btw, I use max for live with a custom calibration and a dc coupled interface to get a much larger range
I'm interested to hear more about this. Max for Live is kind of my thing.

I don't care about accuracy so much as ability to roughly do it.

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mr.sibs
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Post by mr.sibs » Tue Jan 12, 2016 9:53 am

Count me in for a PCB/panel/chip please timo!

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antf4rm
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Post by antf4rm » Tue Jan 12, 2016 10:19 am

TimoRozendal wrote:
antf4rm wrote:
modularaddict wrote:For anyone interested - we've also got these in stock in the US at modularaddict!

SSM-2044 Filter
This would be a good option if there chips available as well.

Anyone have a reliable source for these?
I already have your chip here... just waiting for the pcbs and panels to come in
Excellent! I'll be more patient. :tu:

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Re: [pcb+panel] ssm2044 filter for eurorack

Post by TimoRozendal » Thu Jan 14, 2016 8:07 am

* oops... made a mistake here, ignore this post

brock0791
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Post by brock0791 » Thu Jan 14, 2016 11:28 pm

Guys can we stop with the using parts for eurorack that are essential to keeping legendary units alive?

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grizzle
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Post by grizzle » Mon Jan 18, 2016 7:42 pm

Question: Would it be ok to sub a 12pf cap for the 15pf? I stupidly thought I had 15 pf caps on hand, but don't. The idea of ordering 1 cap from mouser hurts to think about.

Cheers,
Alex
Tunes-----> apartmentfox.bandcamp.com

TimoRozendal
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Post by TimoRozendal » Tue Jan 19, 2016 3:23 am

grizzle wrote:Question: Would it be ok to sub a 12pf cap for the 15pf?
that should work fine

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Post by jackmattson » Wed Jan 20, 2016 11:44 am

TimoRozendal wrote:in response to a question via pm by one of you I decided to look for further options to extend the range, and I found a useful mod:

I changed R16 from 150 to 100k and this gives me a range with the cutoff knob of ~40 Hz to 20kHz (measuring the self resonance peak)

by lowering R16 the voltage increase at the filter cutoff pin of the ssm2044.
with R16 = 100k the rangs is about +-110mV on my build, but the recommended range stated in the datasheet is +-90mV. This mod works fine for me, but please be aware that this exceeds the recommended voltage range of the chip.
EDIT:
Building as I write. The BOM also mentions changing R15 to extend cutoff. Is this a separate safer mod? If so what's the range there?
Will try just the R15/b change for now.
Or in simple terms, I'm not too concerned with over stressing the chip, just tell me what to do for a full range? (What's the risk, that the chip only last 10 years instead of 30?)

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Post by TimoRozendal » Wed Jan 20, 2016 3:29 pm

jackmattson wrote: EDIT:
Building as I write. The BOM also mentions changing R15 to extend cutoff. Is this a separate safer mod? If so what's the range there?
Will try just the R15/b change for now.
Or in simple terms, I'm not too concerned with over stressing the chip, just tell me what to do for a full range? (What's the risk, that the chip only last 10 years instead of 30?)
I would suggest taking it step by step: first doing the R15/B mod (background: original circuit is for +-15v, this gives the same voltage input for +- 12v, btw, this doesn't change the responsiveness to incoming cv of course). This might be enough depending on your specific chip (range varies per chip). If not, simply install a 300k parallel to the 150k that is in R16 (this will make the resulting resistance 100k). Yes, this might reduce the lifetime of your chip, or not... I don't know. In my opinion you should be fine... :lol:
jackmattson wrote: Building as I write.
you should be done by now :hihi: how did it go?

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Post by jackmattson » Fri Jan 22, 2016 12:14 pm

I would have been but I was missing a couple of caps.
BTW at work and making a mouser order (not infront of my PCB) but the pdf only lists 2 Pots and there are 4 on the panel.

Are the other (not P1 and P2) pots also B50k? One is for gain so I would assume that it's AX0k.
Looking here... http://modular.fonik.de/pdf/SSM2044small.pdf

Another question... I ALWAYS get the wrong size trimmers. Do you have part numbers or some key word to search for so I get the ones that fit the holes? (multi turn or single turn)?

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Post by TimoRozendal » Fri Jan 22, 2016 12:25 pm

jackmattson wrote:I would have been but I was missing a couple of caps.
BTW at work and making a mouser order (not infront of my PCB) but the pdf only lists 2 Pots and there are 4 on the panel.

Are the other (not P1 and P2) pots also B50k? One is for gain so I would assume that it's AX0k.
Looking here... http://modular.fonik.de/pdf/SSM2044small.pdf

Another question... I ALWAYS get the wrong size trimmers. Do you have part numbers or some key word to search for so I get the ones that fit the holes? (multi turn or single turn)?
Please use the bom attached to the first post in this thread, this lists all pots (they are all 50k, the input is log, the rest is lin).
I also mention there that the trimmers (singleturn) are 6mm, I use these (type, not value)

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Post by BARE BONES » Sun Jan 24, 2016 4:33 am

what is the resistor value above the P4 Res pot on the control board?
the writing is illegible

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Post by TimoRozendal » Sun Jan 24, 2016 7:14 am

BARE BONES wrote:what is the resistor value above the P4 Res pot on the control board?
the writing is illegible
oops, you are right, something went wrong with the latest batch, it is R24 (4.7k)
Last edited by TimoRozendal on Sun Jan 24, 2016 3:18 pm, edited 1 time in total.

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jackmattson
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Post by jackmattson » Sun Jan 24, 2016 9:30 am

so needed to order from Tayda anyway but they don't have 50k trimmers like that. Would 47k do the trick?
I could also go higher to 100k, and then turn it way down but with a little less precision, right?

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Post by TimoRozendal » Sun Jan 24, 2016 11:04 am

jackmattson wrote:so needed to order from Tayda anyway but they don't have 50k trimmers like that. Would 47k do the trick?
I could also go higher to 100k, and then turn it way down but with a little less precision, right?
They do have the 50k: link but 47k should work fine as well.

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Post by TimoRozendal » Wed Feb 03, 2016 8:08 am

yes, got all in stock again...
will send PM's out immediately (or tomorrow, depends on how much attention my kids need)

the panel looks nice, but the silkscreen is a littlebit off (factory error)... this is very good to see before attaching it, but afterwards it is hardly noticable (the perspective of the knobs has way more impact)

judge for yourself:
Image

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Post by HipDestroyer » Wed Feb 03, 2016 9:53 am

About to put in a mouser order for this project. I found the 10nf poly here: http://www.mouser.dk/Search/ProductDeta ... key23PS310

But can't find a proper 820pf poly (only this with a min. order of 2k and I'm not that interested in poly caps :lol: http://www.mouser.dk/ProductDetail/Xico ... xitMSvY%3d)

Edit, or might this work? I know the leg spacing is 7,5mm as opposed to the 5mm recommended in the BOM: http://www.mouser.dk/ProductDetail/Keme ... I%252b6XH1

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Post by TimoRozendal » Wed Feb 03, 2016 9:58 am

HipDestroyer wrote:About to put in a mouser order for this project. I found the 10nf poly here: http://www.mouser.dk/Search/ProductDeta ... key23PS310

But can't find a proper 820pf poly (only this with a min. order of 2k and I'm not that interested in poly caps :lol: http://www.mouser.dk/ProductDetail/Xico ... xitMSvY%3d)

Edit, or might this work? I know the leg spacing is 7,5mm as opposed to the 5mm recommended in the BOM: http://www.mouser.dk/ProductDetail/Keme ... I%252b6XH1
I think you have a different footprint for the 10nf (I think it is too big), I use these:
http://www.taydaelectronics.com/10nf-0- ... citor.html

I will include a 820pF in your package, I have enough here (bought 20 on aliexpress)

Cheers

Timo

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Post by HipDestroyer » Wed Feb 03, 2016 10:25 am

TimoRozendal wrote:
HipDestroyer wrote:About to put in a mouser order for this project. I found the 10nf poly here: http://www.mouser.dk/Search/ProductDeta ... key23PS310

But can't find a proper 820pf poly (only this with a min. order of 2k and I'm not that interested in poly caps :lol: http://www.mouser.dk/ProductDetail/Xico ... xitMSvY%3d)

Edit, or might this work? I know the leg spacing is 7,5mm as opposed to the 5mm recommended in the BOM: http://www.mouser.dk/ProductDetail/Keme ... I%252b6XH1
I think you have a different footprint for the 10nf (I think it is too big), I use these:
http://www.taydaelectronics.com/10nf-0- ... citor.html

I will include a 820pF in your package, I have enough here (bought 20 on aliexpress)

Cheers

Timo
Amazing, Timo, Thanks!

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HipDestroyer
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Post by HipDestroyer » Wed Feb 03, 2016 12:10 pm

Btw those black panels are gorgeous

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