Presenting: Crowminius

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oberling
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Post by oberling » Wed Mar 09, 2016 12:51 pm

InfraXpert wrote:
oberling wrote: If someone wishes to use it - go for it: crowminius_minimoog_rme.fpd ... but be prepared: it's quite expensive!
Can you be more specific? :ripbanana:
Using this particular file we are talking about 428,71€ for one piece.

I don't know how much that is for outside EU from frontpanel-express (about 387$ at current exchange rates - but Altitude909 mentioned something like 517$).
However oldcrow mentioned that it is possible to bring it down right under 300$ when using a single hpgl objects for all the white filled engravings.
I didn't do this because to be certain: I didn't know better :despair: - learned about this option the hard/pricey way :deadbanana:

Maybe oldcrow could put up his single-hpgl-object version somewhere... ... if he clicked the "save" button :hihi:

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mOBiTh
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Post by mOBiTh » Wed Mar 09, 2016 1:42 pm

you can export hpgl from front design no?

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oberling
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Post by oberling » Thu Mar 10, 2016 3:44 pm

I think I figured out how to do this:
1. export the frontpanel as svg graphic
2. import this svg into inkscape (for it can export hpgl files)
3. remove all non-printed objects including every cross that's visible - all visible objects in your inkscape file will be visible in the hpgl file
4. export as hpgl
5. in frontpanel designer remove all printed elements that reside in your hpgl file now
6. add hpgl object to frontpanel and resize/rotate etc. it accordingly to fit everything

Don't be confused if the fonts are completely out of shape in inkscape: they will be just fine when re-imported as hpgl file into frontpanel designer.
As steps 3 and 5 seem to be quite time consuming I didn't do it by now - maybe future oberling will have more time for it... or someone around here :goo:

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samuraipizzacat29
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Post by samuraipizzacat29 » Thu Mar 10, 2016 3:48 pm

I hate inkscape. If you have a system that can run it, illustrator cs2 can be found on the internets by legitimate means. it will require some googling and effort, but it can be had.
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oberling
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Post by oberling » Thu Mar 10, 2016 4:39 pm

samuraipizzacat29 wrote:I hate inkscape. If you have a system that can run it, illustrator cs2 can be found on the internets by legitimate means. it will require some googling and effort, but it can be had.
well and I sure hate closed source crap :hihi:
so everybody has their own way to deal with things :razz:
does illustrator even support export of hpgl-files?

aside from this I took my time and as svg is a text based format it was a little easier than I expected to remove all green and red elements (remove all elements that contain ff0000 and 00ff00). From there on it was a matter of some clicks to remove the rest... step 5 was a little more tedious but worked as well.
Now I have the other file uploaded here: crowminius_minimoog_rme_single_hpgl.fpd
However some issues remain that would bother me: 1. there is a white frame around everything... I don't know where that comes from. 2. You can only chose one particular tool for engraving which means: every line is of the same width (whereas they were of various widths in the former fpd file) and 3. the round fonts are layed out as lines now which at least looks "different"... I personally wouldn't order it that way... but maybe the pricetag of now 285,81€ is more compelling to some of you :75:

I also left the engraving of "proudly assembled by " as texture in frontpanel designer so you can put in your own name there :hihi:
Disclaimer: I don't know if the file as is can even be ordered - haven't tried and certainly will not try as I already have my perfectly fine but expensive frontpanel :guinness:

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oldcrow
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Q1 2016 v1.1.x board batch arrives

Post by oldcrow » Sat Mar 12, 2016 6:54 pm

Hey folks, the Crowminius board batch for Q1 2016 is finally here. Over half are already sold, so get em while the gettin's good. :sb: :sb:

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peAk
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Post by peAk » Mon Mar 21, 2016 8:49 pm

Hey Crow,

I am finishing up my build and I am having one last issue that I am trying to work out. I thought I had the thing calibrated okay but once I put it all in my enclosure and got my pitch wheel and tune knob centered, I needed to adjust the calibration again.

I am having a little trouble with oscillator 3 again. Last time I was having trouble scaling it right and by changing R94 out to a 85K, I was able to get it scaled properly. This time I can't seem to get the range in tune at 32' through 2'. My scale is fine but I seem to run out of room on my zero and octave trimmers while setting the range. I always run a little flat no matter where I set them. Is it possible to adjust R93 or R95, similar how I adjusted R94, to get the range to calibrate?

Any help would be great.

See below to see how close I am to having this thing done :help:

:waah:

Image

Image

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dalhasumai
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Post by dalhasumai » Fri Mar 25, 2016 10:19 am

I would like one please !

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peAk
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Post by peAk » Mon Mar 28, 2016 9:44 pm

Crow

Any ideas how to "tame" attack the modulation pot some?

I have a A50K attached to a mod wheel but it seems very sensitive in the beginning of the rotation. Like kind of hard to dial a vibrato in before it's too extreme.

I am not sure exactly what the pot taper was like on the original Minimoog but from the videos I have seen, it seems more subtle until you get more than half way up on the wheel.

Not sure if I need to hunt down an original pot or if there is some tweaking you can do to this?

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peAk
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Post by peAk » Tue Mar 29, 2016 7:57 am

just to add, all the pictures of the original minimoog modulation I have seen show only two wires connected to the pot, is this how the crowminius should be wired?

NLS
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Post by NLS » Sat Apr 16, 2016 12:55 pm

Hello there!

Would it be okay if I use 4.7K trimmers instead of 5K like on the BOM??



:help:

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Techman
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Post by Techman » Sat Apr 16, 2016 1:37 pm

NLS wrote:Hello there!

Would it be okay if I use 4.7K trimmers instead of 5K like on the BOM??



:help:
Yes no problem.

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tvh
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Post by tvh » Sat Apr 16, 2016 8:28 pm

peak that is a thing of beauty :tu:

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wahee
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Post by wahee » Sun Apr 17, 2016 4:37 am

Peak you nailed it with that design, really nice
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peAk
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Post by peAk » Tue Apr 19, 2016 9:18 am

Thanks guys

Just an update:

I found this info on old moog forum:

"The mod-pot has only two wires. In full counter-Clockwise postion it should have 0 Ohms. Fully forward (full modulation) it should have 1,2 KOhm. This is a movement of 90 degrees - it´s a miracle, that this 50Kohm-Pot (audio/log) makes only 1,2 Kohms at the first 90 degrees...this is really special. So it will not work if you change it to a simple 50KOhm log Pot. "


I searched hi and low for a suitable pot for the modulation wheel with little success. The tapers on almost every 50K pot just weren't right. It ramped up just too fast. I had a Burns A25K that had a pretty good taper but it just wouldn't get to 0ohms to close the modulation and so the bleedthrough was just unbearable.

Here is some great information from Synthfool (RIP) about some ways to get rid of modulation bleedthrough on the minimoog:

http://www.synthfool.com/docs/Moog/mini ... heelfixes/

In the end, I ended up getting a suitable potentiometer from CAE Sound for a Minimoog replacement pot ($30 pot plus $12 shipping) :woah: :waah: .....but it's a pretty hi-end pot and got me what I needed (very little bleed and correct taper)

So hopefully this info can help someone that goes through this.

I am finishing up now just waiting to get the back panel fabricated.

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samuraipizzacat29
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Post by samuraipizzacat29 » Tue Apr 19, 2016 9:23 am

As a possible solution you could take a pot apart and drop a glob of solder or something over the very end of the resistance disk. The solder will wear over time, but is a fairly easy fix. I would imagine silver solder would hold up slightly better over time.
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peAk
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Post by peAk » Tue Apr 19, 2016 10:56 am

samuraipizzacat29 wrote:As a possible solution you could take a pot apart and drop a glob of solder or something over the very end of the resistance disk. The solder will wear over time, but is a fairly easy fix. I would imagine silver solder would hold up slightly better over time.
Not a bad idea. I was going to do the reed switch method but what I was worried about was that I would have a slight "jump" from no modulation to modulation. The might be the case with adding solder to the disk too. The whole reason this became an issue was it seemed almost impossible to get a nice vibrato before going into deep modulation with a standard A50K.

I am happy with this $40 :waah: pot for now.

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wahee
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Post by wahee » Wed Apr 20, 2016 9:52 am

peAk wrote:Thanks guys

Just an update:

I found this info on old moog forum:

"The mod-pot has only two wires. In full counter-Clockwise postion it should have 0 Ohms. Fully forward (full modulation) it should have 1,2 KOhm. This is a movement of 90 degrees - it´s a miracle, that this 50Kohm-Pot (audio/log) makes only 1,2 Kohms at the first 90 degrees...this is really special. So it will not work if you change it to a simple 50KOhm log Pot. "


I searched hi and low for a suitable pot for the modulation wheel with little success. The tapers on almost every 50K pot just weren't right. It ramped up just too fast. I had a Burns A25K that had a pretty good taper but it just wouldn't get to 0ohms to close the modulation and so the bleedthrough was just unbearable.

Here is some great information from Synthfool (RIP) about some ways to get rid of modulation bleedthrough on the minimoog:

http://www.synthfool.com/docs/Moog/mini ... heelfixes/

In the end, I ended up getting a suitable potentiometer from CAE Sound for a Minimoog replacement pot ($30 pot plus $12 shipping) :woah: :waah: .....but it's a pretty hi-end pot and got me what I needed (very little bleed and correct taper)

So hopefully this info can help someone that goes through this.

I am finishing up now just waiting to get the back panel fabricated.
To be honest I had never thought of checking this. I have been comparing some patches on the Crowminius with factory patches dialed into a minimoog. I had noticed a bit of modulation., as well as my filter cutoff frequency was different.

I also meant to ask Peak if you had any success using modulation over midi. It may not have been implemented yet, must relook over the whole post. cheers
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peAk
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Post by peAk » Wed Apr 20, 2016 2:56 pm

Even with this new pot, I still get a little bleed. It's not too bothersome but it's there.

No, I don't think pitch and modulation were ever implemented over midi. Crow did say there was a work around but it was a little above my head. I got tired of waiting and just decided to use on onboard modulation and pitch pots and wire them directly to wheel assemblies. Obviously this isn't ideal because I can't record and automate like I would be able to if it was midi but I can live with it.

I have been tweaking mine for months and really, REALLY comparing it to Minimoog videos/audio I can find online. There is one youtube video that a guy did where he runs through each and every Minimoog patch and plays it after showing each patch. It's a real good way to compare. Obviously even Minimoogs sound different from each other so none are going to sound exactly alike. I never heard a patch that I couldn't nail even if I had to adjust mine slightly from the patch sheet.

Besides the issues I mentioned previous, I am really happy with everything. I think it sounds fantastic, goes in tune very quickly, stays in tune all day. I wasn't able to get the filter to scale across the octaves correctly but I also didn't spend too long trying. I may revisit it at some point.

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wahee
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Post by wahee » Wed Apr 20, 2016 4:28 pm

haha - I have just been watching the same videos on YouTube and I must say now I have tweaked the filter, it's pretty close. It requires a bit more tweaking on the controls to get the attack and punch right of some of the bass sounds but overall great. I also discovered some of my switches were wired back to front. No big deal though.

Image


The midi mod is not such a big deal although like you, programming it in a DAW is handy.

I love my crowminius and it's been a really great experience to build. It now sounds fantastic.

I was looking at the mods you listed a few posts back. I love SYNC effects and was thinking of trying the mod on the crowminius. Presumably the new OSC mini boards version.

From a quick glance at the PCB is seems that IC8 is the same. Is Q9 the same as Q9 on crowminius I wonder. Having a look now
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resistor values

Post by stringsthings » Thu Apr 21, 2016 11:04 pm

I have a few questions on the value of some resistors. ( REV 1.1.3 )

R22, R62, R100, R378 are listed as 15K in the BOM and on the schematic, but on the board R22, R62, R100 are printed as 0? And R378 is printed as 10K?

Also, R7 is listed as 22K in the BOM and the schematic, but it is printed on the board as 0?

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Re: resistor values

Post by oldcrow » Mon Apr 25, 2016 9:32 pm

Grumble, once again MW is not sending me email notifications.

I will edit an addendum for the v1.1.3 boards, which use an extra bit of circuitry. For R7, R22, R62 and R100 if the opamps they conenct to are 1458s, use 15K. If you use TL072s, they can be jumpered (zero ohms). Either way is fine.

R378 should be 10K.

--Crow
/**/
stringsthings wrote:I have a few questions on the value of some resistors. ( REV 1.1.3 )

R22, R62, R100, R378 are listed as 15K in the BOM and on the schematic, but on the board R22, R62, R100 are printed as 0? And R378 is printed as 10K?

Also, R7 is listed as 22K in the BOM and the schematic, but it is printed on the board as 0?

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Post by gruvsyco » Wed Apr 27, 2016 11:10 am

I'm currently building my V1.1.2.

I'm curious how difficult would it be to modify/adapt this to be full on semi-modular?

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Re: Crowminius Kickstarter Almost Here!

Post by p4rancesc0 » Wed May 04, 2016 11:10 am

oldcrow wrote:I will be launching a kickstarter to build desktop Crowminius units. Watch this space. :sb: :goo: :sb: :party:
Hi, glad to hear this !
Are you doing a new PCB release for the desktop version ?
Sorry, maybe sounds dumb, but I'd like to be 100% sure before I take the standard pcb.
BR
Francesco

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Crowminius Kickstarter is Here!

Post by oldcrow » Thu May 05, 2016 12:13 am

FYI my kickstarter is now LIVE!

Link is available from http://www.crowmini.us/

The kickstarter DIY PCB release is the same through-hole board. The pre-assembled Crowminius will be the exact same circuits, just in SMT for assembly efficiency. --Crow
p4rancesc0 wrote:
oldcrow wrote:I will be launching a kickstarter to build desktop Crowminius units. Watch this space. :sb: :goo: :sb: :party:
Hi, glad to hear this !
Are you doing a new PCB release for the desktop version ?
Sorry, maybe sounds dumb, but I'd like to be 100% sure before I take the standard pcb.
BR
Francesco

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