DIY Synth Rack and Power Supply!

Last time I built a synth module, so now I need a rack and power supply to go with it! Then, we finally test the CEM3340!
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[@SubVengeance]

The fact that the pitch is going down when you turn the knob up is killing me hahaha

[@RussCottier]

How am I only just finding you now...awesome channel...deserves 100x more subscribers

[@theproletkulttn]

Tbh you got me introduced into DIY on the fundamental level as opposed to just kits and the like. I'm still a greenhorn and have a lot to learn, but what an interesting world this is to jump into. Love your videos, can't wait to see more.

[@stephen_hawes]

Awesome!! I totally agree; there's an INSANE amount of info and low-cost equipment out there right now, and it's a great time to get into electronics and DIY audio.

[@robertsyrett1992]

2:35 WTF Dude, you need a serious refresher course in drill safety. You are going to drill a hole in your hand!

[@stephen_hawes]

ahahah i haven't yet!

[@DavidWindsorDCW]

@@stephen_hawes You got lots of super glue, you'l be fine.

[@lowrezable]

Really great work !!! We are starting the same...type of thing thank you !!!

[@untrust2033]

6:35 I'm sorry, but I have to correct you here. In this configuration, where the output of the op amp is connected to their inverting input, it is actually acting as a buffer, and not an amplifier. The reason why this buffer is here is because (I'm assuming,) the 3340 cannot drive an output on its own, as it can not output much current. The op amp will send out the same signal as is fed in through the non inverting input, however the op amp can supply more current making it more suitable for use in a eurorack or in a synth setting. An op amp will always try to keep the inputs the same voltage, so if the output is connected to an input directly, the voltage at the inputs will be the same, and also at the output. This is explained well in video #600 by EEVBLOG, op amps

[@dfautomaton]

An opamp will try to keep the inputs the same when in a negative feedback configuration. The are plenty of other use where this axiom is not true.

[@PermireFabrica]

Well, I'm sorry to correct you, it's still an amplifier! It amplifies current and in the end power if you so will.

[@nelsoncolereis4058]

Hi, thanks for the video! Looks like a cool simple solution. Did you add any decoupling caps or anything to the power supply? Are there any downsides to using it this way?

[@felixXawesome]

Im also thinking of building one of these VCO for my eurorack. Any chance the von layout will be available soon? 😄

[@UNKNOWN-vb1eg]

That is cool. I want to do things like that in the future. Where did you learn these things? How do you get 14-15 age internships that teach things like this?

[@noahscott6997]

Question! Do you have any specifics on the power supplies you had used??

[@Zwedgy]

This channel is amazing. It looks very professional and clean. You need more subs!

[@kgeorgejunior]

Nice!

[@simonburns1055]

can you use a light sabre if you have no laser cutter?

[@philtobin9510]

Stephen, you need to gesticulate more. That is a nice frame though...but for those that don't want to spend thousands on a laser cutter there are cheaper options. One main thing also to remember, hooking up your 0v to mains earth that way, not only is it safer but your 0v stays 0v and isn't a 0v floating reference.

[@stephen_hawes]

Hmm interesting, and to do that I'd likely have to open the 12v bricks I'm using to connect to that rail, right? Do you know why having my 0v reference floating is a bad thing (and why it's preferential to have it be the same as earth ground)? Aside from safety.

[@philtobin9510]

@@stephen_hawes There are lots of opinions on the internet and most are from people/companies that manufacture their own PSUs/bus boards for studio/Eurorack equipment. This is one of many: www.hinton-instruments.co.uk/paprod/psu/index.htm He also has a user on Muffwigglers as well as other forums. There are a shed load of threads discussing this and, in all fairness, give mixed advice that can leave you more confused. Personally I have found my filters have a better response to earthed 0v rails than 0v rails that are not hooked up to mains earth. From what I understand the circuit runs on 12v +/- and the 0v needs to be as close to 0v and stable, I'm sure this opinion will trigger lots of other readers to pipe up with a more accurate explanation and it's welcome. What is also important is you don't run your PSUs at peak load, say your system requires 1A@12v, 250mA@-12v and your PSUs output is 1A@12v +/- It's time to use another PSU and divide the load but don't run the PSUs in parallel, this is a whole new conversation.

[@pollomagico271]

Hi! Could you post the schematic of the power supply? Thank you in advance :)

[@DaKILLaGod]

did you see the power supply here?

[@rainy2063]

I'm going to use old PC power supply with a little bit modification. It's rather cheap and simple just get from it +-12v and ground:3

[@rainy2063]

It has extra +-5v +-3.3v as bonus

[@zourza]

Is it possible to output the different wave forms simultaneously?

[@afi6061]

Yes, you should be able to get saw, triangle and square separately. You can also add a sine if you know what you're doing.

[@alexanderskrabacz3277]

i have this weird organ from a rummage sale called a fun swinger, and i wanna take it appart and put the little rack pieces into it with a power supply and use it

[@jgc9911]

Hey dude can you do an update on the rfid in your hand from 4 years ago. I'm thinking about doing it my self at some point

[@stephen_hawes]

For sure! I'm actually moving soon so I'll do a video on my RFID setup at my new place. Plus I might get a new chip soon!

[@jgc9911]

@@stephen_hawes awsome

[@Sangejzer]

Maybe a dumb question maybe not: I see you connected 3 your modules to the psu with 3 cables. Witch means that either you haven't connected 5v cause you didn't need it or you haven't connected the ground. Which one is it and if it's the second option then can you explain why? is -12v effectively playing a role of ground? I don't think so but I'm a noob.

[@derecwilsom4546]

i have heard the background music very recently but dammit i cannot place it, can anybody tell me what it is?

[@bobbyflay4104]

What was the other circuit you were talking about at the end?

[@stephen_hawes]

This beauty: blog.tommy.sh/posts/prototype-post-mortem-four-step-octaved-sequencer

[@mpingo91]

What material did you use for your case? Doesn't look like plywood or maybe I can't see good enough...

[@JackSisniftee]

Looks like acrylic and some sort of veneer

[@pickleboysupreme]

Are there cad files for this?

[@bashenko]

Hey mate! I find it super strange that you use TWO POWER INPUTS to make bipolar power supply. It is the most extravagant method I’ve ever seen. I’m on my stage of subject research now. I’ve seen this video last evening and couldn’t sleep after that :)

[@drjmansplace5174]

Are you aware that the 555 timer can generate saw, triangle, sine, and noise?

[@lucasc5622]

have fun tracking it to v/oct lmao

[@AshBashVids]

Where's the trimpot? Why are you putting a modular level signal straight into an amp? Surprised you didn't blow it the cone!

[@wesleymays1931]

That power supply layout does work, but I don't really like it... I would've used an old computer power supply. Or a 12V wall wart, and a MUCH more complicated circuit in the rack: 1). The 12V input has a bit of bulk decoupling and a fuse, and goes to +12VUF (Un Filtered) 2). +12VUF goes through an ICL7660 voltage inverter to get -12VUF 3). +12VUF goes through a 2-stage Capacitance Multiplier to get +12V 4). -12VUF goes through a 2-stage Capacitance Multiplier to get -12V 5). +12VUF goes through some kind of buck converter to get +5V 6). +5V, +12V, and -12v have a bit of bulk decoupling, and go to power the modules At least this way you only have one barrel jack :D

[@DaKILLaGod]

2:17 equipment cool, hands lool.. btw where are the front, bottom and rear parts of this cabinet? is it just this thin thing? it will collapse under some real stuff on the first real party.. :-D

[@eughcus]

bro your coarse pot is also flipped (normally when rotated clockwise it raises the pitch), I think you just put the entire PCB upside down? :) well, yes, it's too late to assume anything since the vid is posted 4 years ago, but anyway

[@Manu2126]

stephen the robot??

[@danriera7774]

UCONN!

[@slick8086]

Maybe this is a little late, but the Eurorack standard IS defined by the company that "invented" it. That doesn't mean everyone follows it, but it does exist. Here are the documents www.doepfer.de/a100_man/a100t_e.htm www.doepfer.de/a100_man/a100m_e.htm www.doepfer.de/DIY/a100_diy.htm

[@rainy2063]

Cem3340 isn't important It just makes things easier but more regular and expensive:/

[@guysmiley7289]

all you need is 10k in machine equipment