Do it yourself crew in the house?

[TubularCorporation]

Two MIDI_IO boards for the Midibox SEQ, but with headers for the MIDI jacks so I can mount them inside stacked like that and connect 8 panel mount MIDI jacks instead of putting them on the PCBs - easier and more durable.

 

Yeah, the world of fake ICs is interesting.  I've got a pile of suspicious voice chips for the Matrix 1000 that I got cheap on Aliexpress.  They look very real but I doubt it.  I've got two I know are real, so if I ever have to replace one I'll install a socket and test all the likely fakes first.

 

It's a really big business and kind of fun to read about.

https://www.aeri.com/counterfeit-electronic-component-detection/

https://www.engagez.net/posting/29099?snc=0

https://atadiat.com/en/e-introduction-counterfeit-ics-counterfeiting-detection-avoidance-methods/

 

For what it's worth, none of the Aliexpress CEM3396's have any of the signs of fakes, they're perfect matches for the real ones I can find online and I can't see any blacktopping or anything, the suspicious think is that they were $6 each and I bought them at least 5 years after the last known NOS wide body 3396's had sold out for almost $100 each.

Edited June 27, 2020 by TubularCorporation

[TubularCorporation]

I've also gotten some perfectly good, non-rare, in-production ICs from major vendors over the years that look REALLY fake but work fine, so it's hard to tell.

[Hautlle]

Through all my research and reading on the rollz paper circuits I found out Meng Qi made a machine based off of them and ended up ordering a Rollz-5 PCB that should be here this week.  Just bought everything for the build including banana cables (not cheap ).  Hopefully can work on building this in a few weeks and figure out how to edit the svg case files for some changes I want to make.

 

Edited June 28, 2020 by Hautlle

[TubularCorporation]

Banana cables are really easy to make yourself, and also you can get pretty decent ones cheap if you buy them as test leads.

 

These aren't anything special but they're fine:

https://www.amazon.com/gp/product/B07179VF5J/

 

This is really nice wire you can use with your connectors of choice:

https://www.amazon.com/gp/product/B018H1BDP4/

EDIT: that's assuming you want a really flexible wire, but for a desktop synth that can actually get in the way more; for stiffer wire I don't have any suggestions, jsut get something with PVC insulation instead of silicon.

 

These plugs are pretty good for $1 a pair, and 16AWG fits them really well but they're a little tight inside so you have to be efficient with your soldering:

https://www.ebay.com/itm/10PCS-Stackable-Soldering-Banana-Plug-Connector-Test-Probe-Binding-Post-5-Colors/163814682226

I haven't tried these but they look like they might have a bit more space inside for the solder joint:

https://www.ebay.com/itm/10PCS-2mm-Stackable-Banana-Male-Plug-Gold-Plated-Connector-for-Speaker-Amplifier/163747782966

 

 

For me the trick to making them quickly, reliably and without burning myself is to open up the plastic housings on all the plugs and take the metal pieces out.  Have a hunk of 2x4 with some holes drilled in it that you can plug them in (I forget the right size, 4mm, maybe 4.5).  Then you can easily assembly-line them and not worry about stuff moving around while the solder cools (you want to really heat them up a lot to make sure you get a good joint).  Once you get a feel for it and figure out the best spot to solder the wire on so it fits well in the housings of the plugs you chose, it's actually really satisfying.  I spend about an hour doing it a few months ago and now I have at least three times as many cables as I could possibly use because I just kept going.

A solidly made 1 meter DIY banana cable costs about $2.50 USD and takes less than a minute to make.

 

Even though you already bought some, no reason not to make some more - they stack so well that you always need more than you think you need.

 

Edited June 28, 2020 by TubularCorporation

[sweepstakes]

I ordered the wrong pots for some projects. They're hella short. Now I'm stuck with these stump-dick pots. Has anyone tried something like lengthening them w/ screws and spacers? Or is that doomed to fail when the knobs turn CCW? I might just have to do some shitty Arduino project so as not to waste them.

[TubularCorporation]

Never tried that.  I've had plenty of times when I accidentally got pots that were like 2" long and had to saw and file the shafts down, but not the other way around.

Are they plastic or aluminum?

[user]

I can’t think of any way of lengthening pots that isn’t bound to look horrible, break easily or a scam. 
Maybe some tall knobs that don’t slide all the way down the shaft somehow? 

[Hautlle]

51 minutes ago, user said:

I can’t think of any way of lengthening pots that isn’t bound to look horrible, break easily or a scam. 
Maybe some tall knobs that don’t slide all the way down the shaft somehow? 

I have put a small piece of heat shrink tubing on a knurled pot shaft to keep the knob from sliding all the way down the shaft and rubbing on a faceplate of a project before. 

Maybe try making a slot in the top of the shaft to receive a tail off the extending part and then using heat shrink tubing as the "tape"?  Could work, but these kinds of things usually end up too fragile for actual use.

[sweepstakes]

I'm probably SOL on the stump pots. I ordered something more comparable to what I needed on Mouser. It'll still take some jerry rigging to squeeze the pins into the PCB (7.5mm vs. 5mm) but that's not nearly as severe a hack.

Thanks for the ideas, y'all. New plan - any cool ideas for stumpy 100k linear pots? They're probably a bit much for, say, a passive mixer, eh? Hmm... maybe passive attenuators. I need some of those anyway.

[Hautlle]

I had to put quite a bit of time to find all the pots I need of equal shaft length + knurled so I can use some knobs I ordered years ago on the Rollz-5.

Not sure how long it's gonna be until supply comes back to normal 

Never tried DIY cables before @TubularCorporation - might have to look into it more for the future.

[TubularCorporation]

Banana cables are by far the easiest cables to DIY, it's basically like soldering a piece of wire to a nail.  Only difficulties are that depending on the speciic jacks you might have to be careful about soldering neatly to make it fit, and because the plug part is a pretty big hunk of metal you need to really heat it up to get good wetting, and that means it takes longer than usual for the solder to cool so you have to be kind of careful about keeping everything really still to get a good joint.  IF you have a thick board with 4mm hokes to stick the bare plugs on and one of those "helping hands" things to hold the wire still while it cools they it's easy. While the first end is cooling you can solder the second end, and then while the second end is cooling it should be OK to put the plastic housing on the first end and in the en every cable takes less than a minute.

 

Eurorack patch cables are more tedious and usually not worth the hassle IMO. You don't realy save much money per cable unless you need them really long, and making a decent one is a lot of work, - stripping the inner and outer wires, crimping, soldering, shrink tube, making sure you don't forget to thread the cable through all of the parts of the jack in the right order before you solder.

 

 

[TubularCorporation]

 

The only thing I could actually wire up today is the power switch, but the rack rails are out for delivery and once I have those I can start working on a real enclosure.  Once I have the enclosure designed and at least the ends and bottom built I'll know where everything is going to be and then I can hook it all up.

 

USB jack should be here in a few days, too, but I don't need that to get started.

[Hautlle]

11 hours ago, TubularCorporation said:

Eurorack patch cables are more tedious and usually not worth the hassle IMO. You don't realy save much money per cable unless you need them really long, and making a decent one is a lot of work, - stripping the inner and outer wires, crimping, soldering, shrink tube, making sure you don't forget to thread the cable through all of the parts of the jack in the right order before you solder.

 

 

That's exactly why I haven't tried messing with DIY cables.

 

I could easily make a jig for bananas out of some scrap lumber I have in the garage. Will certainly give it a try in the future

Edited June 30, 2020 by Hautlle

[TubularCorporation]

Making progress.

 

Not sure if I'll make a wood panel to cover the front edge of it  or use more of the thin aluminum I used for the bottom panel.  Both options have their issues. After lunch I'll be drilling holes in the bottom panel to mount all the PCBs and then wiring up the power and MIDI jacks so it's back to a usable state. Should have no problem getting all of the wood parts shaped, sanded and finished by the time I go back to work next Wednesday.

 

It'd be a lot faster if I wasn't limited to hand tools and whatever scrap wood and aluminum I've got lying around, but I think it hits the "70s kit microcomputer" aesthetic I'm going for pretty well.

 

100% coincidence that the top board I found in a discount bin at a woodshop a decade ago was exactly the right width already to the millimeter and just needed to be cut to lenth.  No idea how that happened, I hadn't even thought about using it when I laid everything out, and the spot where I put it is a completely arbitrary length that was just based on roughly placing the PCBs to make sure I had enough room without too much wasted space, I didn't even measure it.

Edited July 1, 2020 by TubularCorporation

[thawkins]

This looks so cool.

[psn]

What is it? 

[Silent Member]

MIDIbox SEQ V4  

[Hautlle]

Got most of the Rollz-5 built but ran out of the nice machined SIP sockets that I'm using to hold all the user-selected components for easy swapping. Sadly the power switch I got is the wrong size (miniature toggle that didn't state miniature anywhere)  

I've got more SIP sockets on the way but I'm feeling like a moron trying to find a simple SPDT ON-ON toggle switch with the correct 4.7mm pin spacing. It's getting annoying with a ton of stock being sold out. I don't really want to drop $6 + s&h for a simple toggle.  I figure I can just put a jumper across the connection for now and unplug when not in use.

 

edit: found a switch for a couple of bucks 

Edited July 4, 2020 by Hautlle

[TubularCorporation]

Nice.

Really interested to hear how that thing sounds.

 

 

I've got some synth stuff on the back burner for building maybe in the fall but the next thing I'm going to do is get a Raspberry Pi 3 and install PocketVJ on it (a prebuilt pocketVJ system is like $800 but it's open source, so if you're willing to deal with the hassle of compiling and setting up everything you can make one yourself for around $70 depending on the price of the RPi + enclosure + SD card), so I can load the SD card up with video clips and set myself up to do simple clip triggering with speed, start time and end time control via MIDI from the MBSeq, so I'll basically have a video sampler.

 

Then I'll start ripping of EBN hard.

 

Finally filed taxes yesterday so I'll pick that up when the returns come.

 

EDIT: can you link a photo or part number or datasheet or something for the switch you need?  I might have one and if I do I'd send it to you.

 

EDIT 2: NM I see your edit.

Edited July 4, 2020 by TubularCorporation

[TubularCorporation]

Pretty much done.  In a week or two when I order the Raspberry Pi I'll also get some covers for the unused holes in the lower rack panel, and I have to clean up the front left corner of the aluminum bottom panel and drill and tap a couple holes so I can screw the back edge of the bottom panel to the lower rear panel but that's not a big hurry, I'll probably wait until whenever I build an ethernet board for it since I'll have to take the bottom panel off and drill for that anyway.

 

Obviously I still need to make the CV output section and I'm waiting for a USB pass-through to show up.

 

Didn't worry too much about the finish since I was just using scrap wood and didn't bother filling the pores in the oak or filling the tearout and knotholes in the other pieces. Anyway, the only finish I have handy is the last of an 8 year old can of KTM-9 (discontinued water based varnish) that I'm surprised even works at all (and it's high gloss, yuck), so I just put on three or four coats of that about an hour apart with minimal sanding in between, enough to keep it from getting dirty.

 

At some point the lower right corner of the rack rails got out of whack, too, that was flush when I glued everything up. Whatever.

 

 

[Berk]

I haven't even looked up yet what that thing does exactly, but it looks sexy as fuck

[TubularCorporation]

It's a really deep, open-source MIDI/OSC/CV step sequencer. Not good for MPC or DAW style linear sequencing (everything's quantized and every parameter and note layer on a track shares a single gate per step, so it works more like an Elektron sequencer than like an MPC style sequencer) but for step sequencing it's insane how much it can do.  I'm still just getting started with it so if you really want an idea, take a look at the beginner's guide:

 

http://wiki.midibox.org/doku.php?id=mididocs:seq:beginners_guide:start

 

If you get the panels made out of something other than aluminum you could build one for around $300. I'd say I'm in about $550 spread over about 4 years and more than half that was the panels, but I haven't built the CV output section yet and that'll probably add another $60-$100 depending on the jacks and enclosure I end up using)

 

So it's not inexpensive, but if you're good at sourcing parts you kind of end up with a fully-loaded Sequentix Cirklon for about the price of a Squarp Pyramid and you don't have to pay for the whole thing at once.

 

EDIT: it ended up being pretty different, but the look was very loosely inspired by my favorite early home computer design of all time:

 

 

Definitely going to swap in some orange-on-black OLEDs at some point.

Edited July 4, 2020 by TubularCorporation

[user]

It has that look that would have me mesmerized as kid and I'd dream of understanding and operating a machine like that just because it looks so fucking cool. Still affects me as an adult but I've let go of the understanding part of the dream : )

The mobilized omar looks pretty slick as well! Inverted the trays and cut the legs on mine, seems they lend themselves quite well to some modification although I'm weary of putting anything too heavy on it with the trays upside down.

[TubularCorporation]

It's actually this one:

https://www.homedepot.com/p/Seville-Classics-Industrial-All-Purpose-Utility-Cart-NSF-Listed-SHE18304BZ/203668363

 

The top is Ikea, though - it's a surplus tabletop from the bargain corner at the Ikea north of town, was a buck or two. Also the post on the left side that I hag headphones and cables from is a bed leg from the same Ikea discount corner.

How do you keep the shelves on upside down?  The way metro-style shelving works the shelves should just fall off it you turn it over...

Edited July 5, 2020 by TubularCorporation

[TubularCorporation]

1 hour ago, user said:

It has that look that would have me mesmerized as kid and I'd dream of understanding and operating a machine like that just because it looks so fucking cool. Still affects me as an adult but I've let go of the understanding part of the dream : )

That's pretty much what I was going for, making it look like something that would have fascinated me as a kid if I saw it in a storage closet at my dad's work.  IT makes it inspiring to use (i.e. it makes me feel more talented than I actually am because I'm using it).