log: building Oakley modules in dotcom format

[kdjupdal]

I've decided to build a couple of Oakley modules for my dotcom format synthesizer. No problems yet - just thought I would write a small log. I have built a few modules before, so I'm confident that it will turn out well.

I had forgotten how much time it takes, though. Ordering parts, sifting through parts, soldering... Soldering is fun, but I work carefully and very slowly.

So far I have soldered the Dual LFO and an ADSR.

[kdjupdal]

I have never used the pot brackets before. I realise that I should have fixed the pots to the panel, before soldering the pots, to ensure they are evenly lined up. Or how do you normally do that?

[Leverkusen]

I think I usually solder one of the pins of the pot brackets with post and bracket placed on the PCB and then screw the pots to the panel, get it in a nice angel and solder the rest of the pins. Wait, or do I start by solderin one pin of the pots? Anyway, yes fixing them to the panel before doing the whole soldering is the key for having pots, PCB and panel in the right angles to each other. After that I do the LED's and switches, again first attaching them to the panel and then soldering them to the PCB. I love it when panel and PCB come together and suddenly look like a real thing.

[Synthbuilder]

Or how do you normally do that?

The way I do it now is to fit the bracket to the pot and hold it lightly in place with the pot nut. Then I place all the pots, with their brackets if they have them, into the PCB. The board is then upturned and just the middle pin of each pot soldered. I then gently bend the pots that aren't sitting at the correct angle and remove all the nuts holding the brackets to the pots. The pots are then inserted into the panel and the PCB is gently aligned to be ninety degrees to the panel. For each pot I then solder the two outer pins. When all the pots are soldered I then reflow the middle pin of each pot. This prevents any unwanted force remaining on the middle pin when the pots were aligned with the panel. You can sometimes see the pin move a little when the solder is melted.

Now I test the board. If all the pots work, then I solder the pot brackets.

This is slightly different to the method given in the Oakley Sound Construction Manual. I have plans to update the Manual over the next couple of months - it's been a while since it's had an edit.

[kdjupdal]

I have just testet the ADSR and it works perfectly! Some of the things that I like about this envelope generator is the linear attack and exponential decay. Also the exponential response of the pots.

I am designing a panel myself. Inspired by the moog 911 design, I wanted to show the time in seconds and ms on the panel. So I need to measure the attack and decay times at different settings. I tried to do it by ear, but I realise it is almost impossible without an oscilloscope, so I should get one. I tried to measure 1 second attack time - seems like it is somewhere where the pot is set on the photo.

[kdjupdal]

I am pondering one idea - is the ADSR out really necessary, and what would I lose if I left it out, keeping only 3 jacks? The VCA out will give the ADSR out signal when the VCA is not used, and when it is used you'd want to use the VCA out anyway. Or what do you think?

[Leverkusen]

Sometimes I use the same envelope that going to the VCA for the filter or a waveshaper or another VCA for FM or LFO amount. What would you gain saving one jack?

[kdjupdal]

I've designed a panel for the ADSR and the VC-ADSR. I already built one ADSR, and I decided to change a capacitor and a resistor (on advice from Tony) to achieve slightly less extreme range. Anyway, I measured the times of my module and included them on the panel. Don't know if it is practical or not... it will of course be approximate.

What do you think?

As for an adsr-out jack... on the VC-ADSR I have space on the panel, but I could also mult the vca-out jack and have two identical outs? That could also be useful.

[Leverkusen]

I like the ring dials! The logarithmic looking scale makes it feel so scientific.

How did you design them? I am about to make some MU panels too for my next Oakley builds, actually the panels are already done and some are also painted black and in blind panel state. But I struggle a bit to find a way to design the scales that is not overly complicated. Or would you mind sharing your templates?

Also why did you condense it in a way that three jacks seem to be better than four? I understand that you don't need the fourt output, but would be interested to learn why you prefer it that way?

[kdjupdal]

I like the ring dials! The logarithmic looking scale makes it feel so scientific.

How did you design them? I am about to make some MU panels too for my next Oakley builds, actually the panels are already done and some are also painted black and in blind panel state. But I struggle a bit to find a way to design the scales that is not overly complicated. Or would you mind sharing your templates?

I use a free design software called "GravitDesigner". With this kind of software you can do a lot, but it takes time to learn it, so for the tick marks I have to admit I used the files on the yusynth website as template. Anyway, I can share my designs if you want to use them as templates.

Also why did you condense it in a way that three jacks seem to be better than four? I understand that you don't need the fourt output, but would be interested to learn why you prefer it that way?

To have space for the module name on the top, and I like the more simple design.

[sonoresstudios]

What is your plan for the manufacturing of the panels? engraving? silk screened?

I have made prototype panels made of plexiglas and printed paper for labelling, for now...but i want aluminum. Not sure which way to go for text etc.

[kdjupdal]

I plan to have them made for me by someone... there are several now that offer to make MU panels.

[sonoresstudios]

Do you have any links?

[anto32]

Also interested in finding a MU panel maker. Unfortunatly Ben at Re:synthesis seems too busy for some time now

[kdjupdal]

Re:synthesis is one option. A pity if they don't take new orders.
Others are Lower West Side Studios, (allthough he said he would close his panel making business), tardishead here on muffwiggler, or analogcraftsman.com. I think there are some more.

[Flareless]

We offer a full range of panels for the modules produced by Lower West Side Studio, including Oakley, for sale.

We're also working on the best procedure to keep our production efficient and cost-effective for custom orders.

You can check out our Oakley lineup here to see which panels are available.

One note; Lower West Side Studio Oakley panels will NOT fit the SOCK series of PCB/Jack combinations. Jacks must be hand-wired.

Any panel inquiries can be made here

[kdjupdal]

Happy new year!
I've had a month break. Time to continue this building project. I'm almost regretting starting it, as it is a lot of work, but I need to finish it. My plan is 2 ADSR, 1 VC-ADSR, 3 VCA, 1 VC-mixer, and the dual-LFO.

[kdjupdal]

I've built another ADSR. I found when I tested the vca on it that it had an ugly overdriven sound - everything I fed through it became a pulse wave. I guessed it could be because of a faulty chip. Since I know the LM13700 is used for vcas, I suspected that chip could be the culprit, and it turned out to be correct. With a new chip it works beautifully. I am still contemplating values and timings of the ADSR.

[kdjupdal]

Hi!
I've finally pulled myself together and managed to finish two ADSR-modules. Panels from Lower West Side Studio. Quite happy with the result.

[kdjupdal]

Dual LFO.

I made this panel design a couple of years ago. Because the distance between the pots is different, I couldn't use the pot brackets. That's a drawback, since the pot brackets makes everything very simple: no wiring, and I don't have to scratch my head wondering how to attach the PCB.

I used this aluminum plate, and it is only held in place by the two switches. I realised later that because of this the PCB will be on the "wrong side" and upside down, making the wiring more complicated. But I didn't want to go back and make a new PCB holder system. Anyway, the LFO works.

[Flareless]

The modules look great! It's wonderful to see them assembled. Great job

[kdjupdal]

Power between PCBs.

I'm building the VC-ADSR. When I connect power between boards, is it a bad idea to merely solder 4 bare wires directly to the boards, without connectors? Is it best to use insulated wire?

[Synthbuilder]

When I connect power between boards, is it a bad idea to merely solder 4 bare wires directly to the boards, without connectors? Is it best to use insulated wire?

Personally, I'd make sure that at least one end of the connecting wires is a connector. That way you can separate the boards without soldering.

And definitely use insulated wire. Preferably multicore wire and not single strand wire.

Always tin the wire ends with a bit of solder before soldering wires directly to boards. This helps clean the wire ends and prepares them for soldering them into the board. If you don't tin and the wire surfaces are slightly oxidised then the wire will need to be heated for longer which could damage the pads. This is unlikely with the MOTM power header pads as they are large but can happen with the smaller pads used on the 0.1" headers.

Tony

[kdjupdal]

Hi!
I'm back! You thought I'd given up this project by now, didn't you?

This thread made me feel guilty for not finishing and held me accountable.
I'm finishing up three classic VCAs. By the way I think I found a small mistake in the documentation: Bourns 3396 should really be 3296, right?

I noticed that I have ordered the wrong kind of jacks: 112APCX are pcb-mount, while I wanted solder lugs (112AX). But maybe it doesn't matter. Isn't it just as good to solder a wire to the pin? See image. The middle module has 112APCX jacks and I've got 100 of them.

[Synthbuilder]

Bourns 3396 should really be 3296, right?

Indeed it should. I have just updated the Builder's Guide. Thank you for letting me know.

Isn't it just as good to solder a wire to the pin? See image.

I used the APCX version in all my builds even before I went to socket boards. I simply made a standard lapped solder joint where the tinned wire is soldered flat against the socket's pin. I then used a 10mm length of suitable heat shrink tube to hold it firmly into place.