Show HN: I built a synth for my daughter

https://bitsnpieces.dev/posts/a-synth-for-my-daughter/

1278 209 8 months ago

skrebbel• 8 months ago

wow

greasegum• 8 months ago

This is an inspiring project! I would love to see more stuff like this and updates if you decide to evolve the project further.

random_moonwalk16• 8 months ago

Thanks so much! Please drop your email here and I'll keep you updated with any next steps: https://tally.so/r/Y55dXv

lovegrenoble• 8 months ago

Absolutely, Kickstarter is a good idea

eat_your_potato• 8 months ago

Reminds me of the concept of the Data DUO, very inspiring

0xdada• 8 months ago

Wow! Looks great and very inspiring. Great idea to make separate components that can be connected - something like a drum machine, sequencer, maybe even a chord synthesizer? It can be constrained such that you are always diatonic, you could have a mode knob too.

Jamming with other people can be a life changing experience, and to do that as a child would be a great privilege to have.

random_moonwalk16• 8 months ago

Yes exactly, it would be great to be able to sync the clocks so they all ‘just work’ together. And maybe also a module that gives all the other synth parameters for the more advanced user too. I say it’s for my daughter, but I actually would love this too.

andoando• 8 months ago

Im not sure youre aware of this but look up modular synthesizers. This is how electronic music was made starting in the 60s/70s

nimrody• 8 months ago

It's beautiful and the demo video shows how someone with music background can make even such a limited tool sound so amazing.

dmd• 8 months ago

Very cool. Reminds me of things like the Blipbox myTRACKS and the CHOMPI.

fiatpandas2• 8 months ago

Regarding case material for productizing, you could consider a combination of plywood and bent sheet metal, eg like a Moog. Also check out dato.mu for a few examples of kid proof synth enclosures.

Thorrez• 8 months ago

Would bent sheet metal have any sharp corners or edges? For kids it's probably best to avoid those.

bluGill4• 8 months ago

That depends on how much effort your spend on finish work. Files and sandpaper works wonders, but that take time. Or you can fold the edges over so that the sharp edges are on the inside (cars do this). The plywood is likely to cover all those sharp edges - plywood is easier to shape than sheet metal so this is a common cheat that can look good if done right.

fiatpandas2• 8 months ago

You can debur it as part of the manufacturing process, and then when it gets powder coating it smooths out even more. But you can just embed the sheet metal edges in a groove on a wooden side.

dude250711• 8 months ago

Another good option for a child: https://www.eltamusic.com/solar-42

On a serious note: https://www.ericasynths.lv/shop/standalone-instruments-1/bul...

eitally• 8 months ago

Perhaps more realistically, Teenage Engineering products: https://teenage.engineering/store

persedes• 8 months ago

yes, the pocket operator is a great gift for 8-9+ year olds if you're not as talented as OP :D

nrhrjrjrjtntbt• 8 months ago

Why is the first link not serious?

tanepiper• 8 months ago

I'm a 44 year old man and I would love this - for years I've tried to dabble with music with much lack of success - but this looks really fun to play with. Great job.

bluGill4• 8 months ago

The problem with music is you can't dabble. You need to dedicate half an hour per day for a few weeks before you reach the point where you are not terrible. You need years of dedicated practice before you can call yourself good. Finding that time is hard. Still making your own music is run and so I encourage you to press through.

exitb• 8 months ago

Not trying to get good is a liberating step. I never was and never will be good at music, but it’s still fun to play loud punk-ish tunes on a guitar, or twiddle the knobs on a faux-303, none of which requires years of your life.

0xMalotru• 8 months ago

Go grab a Teenage Engineering Pocket Operator, it's definitely worth a try ! I personally recommend the PO-33 (KO!), it is fun and easy to play with :)

semi-extrinsic• 8 months ago

The POs are fun to play with, but from experience I would much rather recommend getting a used mk1 Novation Circuit. For $150 - $200 you have a four track drum machine plus two tracks of a great synth engine, with a built in mixer and simple effects, midi in if you want to use a keyboard, and the thing is still compact and battery powered.

fainpul2• 8 months ago

There are also free software synths and DAWs available. GarageBand is the obvious one if you use macOS. I had lots of fun with that and with NanoStudio on iPad. I also own a Pocket Operator, which is fun and very mobile, but a bit pricey.

turbotim• 8 months ago

I've been messing around making a small web based project that does something similar if you're interested in trying a dabble: https://shantylab.com

haldean• 8 months ago

If you want a synth you can buy that has a similar playing style, you could check out the Modern Sounds Pluto: https://www.modernsounds.co/pluto (the original run is sold out but you can find them on ebay/reverb)

It's two of these 4-note step sequencers with some fun timing randomness. Similar to the OP's synth it uses knobs to set pitches but the knobs are picking notes from a specific key so they always sound good together. It's a lot of fun to play and doesn't require any musical knowledge!

BjornW• 8 months ago

What an awesome project. It looks fabulous!

Reminds me of the Dato Duo I have.

The "Dato Duo" is also a synth aimed at kids. It allows 2 kids to play together. it is made by a Dutch company called Dato (https://dato.mu). Their latest musical invention the "Dato Drum" had a successful Kickstarter and is shipping now. This drum machine allows even more kids to play together.

PS: As the owner of a Dato Duo I can share you a little secret: it's also fun for adults :)

perelin• 8 months ago

Love my Datos (also own the drum now)! My kids are jamming with them regularly. Only issue: my youngest LOVES the "Crush" button and just holds it the whole time. Not easy for noise sensitive parents :)

Waterluvian• 8 months ago

If I have zero experience designing PCBs but wanted to do a similarly (non)-complex one, how much of a tall order would that be? In my completely made-up mental model, I'm guessing I just take the parts I've already breadboarded, look them up in some sidebar, and drag and drop them around, snapping to nice clean spacing, and then connect all the various pins together and have it automatically organize things? We're not going for perfect here. Just "Baby's first PCB" that at least works.

And then when I have one designed, how much would it cost to get made and sent to me if I was okay if it took a month?

But most importantly: how do I build personal confidence that I'm not shipping a potato off to be printed? Is there a community I could ask for a review from?

jmb99• 8 months ago

If the board is small (10x10cm or less) it will be almost completely free, like single-digit dollars, through somewhere like JLPCB. So I’d say don’t worry too much about that, just jump in and try!

As for actually designing, it’s a little more complicated than that but not by much. I did my first pcbs with KiCAD ~5 years ago by pretty much just guessing and googling where things were. Completely feasible if you have 0 background experience.

random_moonwalk16• 8 months ago

Hi, your mental model is essentially correct, though it took me a good few evenings over a couple of weeks to get the workflow down in fusion 360. The electronics retailer will usually have the footprint and 3d model available on the component page. You can then import it, define which pins you want connected to each other in the footprint and in the PCB editor you can drag the routes (wires) to connect them.

Printing is way cheaper than I initially thought it would be - I paid £35 or so, including delivery and 5 of them arrived in 5 days. You can get cheaper delivery though. Also most of that cost is shipping and the setup fee - the marginal cost for each additional PCB print in the order is on the order of low single digit dollars.

Tbh my circuit was fairly simple so I just took a bit of a chance (and some extra care wiring things up). I think there’s a subreddit where people give feedback though I haven’t submitted anything.

bluGill4• 8 months ago

Depends on complexity. The article gives a price, for 5 PCBs which isn't unreasonable. However this was a simple PCB that used a lot more physical space than it would need to (for this application most of the space was needed because of the physical space the buttons/sliders needed so it was needed so this isn't a criticism). If you want to make a small PCB much more work is needed. This was a few analog sliders and buttons - no high speed digital data, if you are designing a computer (even Apple II level complexity) it is a lot harder. If you are designing a radio there are a lot of complexity. If you want to get this FCC (whatever your local government is) certified there is a lot more complexity.

This project is something that should be easy for someone with basic CAD experience. However many projects require a lot more complexity, so don't think that because most people could figure this PCB out in a day make you think anyone can do more complex PCBs, things get complex fast.

TheJoeMan2• 8 months ago

As a hobbyist, I have had a good experience using EasyEDA [0]. It's free to use, with the caveat that you are pretty locked in to their PCB ordering service from China. However, pricing is crazy good, like <$50 total for 5 PCB's (although there will be tariffs).

Regarding your mental model, it's more like a 2-step process. First, you draw the netlist, which is the electrical circuit diagram. It's this stage you ensure there are no short-circuits, etc. Then in the second stage, you drag-drop the components to the physical layout you want. The software then has an auto-router that references the netlist and automatically generates the first pass of PCB traces. You can tweak them if you wish. The EDA software also has a rules engine that checks for correct trace spacing, vias, etc.

For a "baby's first PCB", I bet you have more skills than you realize and I would encourage you to just give it a shot. Also, if you make a small mistake, you can manually "bodge" the board by cutting wrong traces with an exacto knife and/or soldering wires to the pads.

Everything else just comes from experience! If you're staying in the sub-kHz (audio) range, you probably won't need the crazy high-frequency tricks/trace capacitance/trace-length-matching concerns.

[0] https://easyeda.com/

meatmanek2• 8 months ago

Does EasyEDA not allow you to download gerber files anymore? Gerbers are universal and you'd be able to send them to any fab you wanted. Obviously EasyEDA being sponsored by JLC means they make it easy to order through JLC.

drivers99• 8 months ago

jmb99 already said the part about cost/price. I just made a PCB for someone’s Halloween costume and it was only the 4th PCB I ever made. (So far I’ve used PCBWay for all 4 but since I’m in the US I also ended up doing a rush order from US-based Osh Park because I was panicking about how long the shipping was taking. Tariff situation has made shipping from China to the US more complicated. I found out DKRed, which is part of DigiKey, also makes PCBs in the US.)

For designing it I’d check out a kicad 9 tutorial playlist. You don’t need to know everything but it helps to know the right things, like how to run the design rules checker to make sure your PCB layout conforms to your schematic. There are a bunch to choose from but this one seems good: https://youtu.be/4YSZwcUSgJo

I haven’t done this but you can also try submitting your PCB design to /r/PrintedCircuitBoard subreddit for review, and they can also answer questions there.

meatmanek2• 8 months ago

+1 to /r/PrintedCircuitBoard. It's exactly the community GP is looking for.

tmerr• 8 months ago

For another data point: last week I ordered my first PCBs from JLCBCB. 2 fully assembled (parts already soldered) and 3 bare. $40 for the boards themselves, $40 for shipping, and $20 for US Tariffs, for total $100. Should take a week to arrive, shipping's cheaper if your willing to wait a month.

Re help: I asked for some help on libera ##electronics. I think there are larger communities on reddit that would also take a pass over designs.

My impression is that for straightforward circuits (not very high frequency or high power) you can get away with almost anything as far as layout goes. You punch in some generous setting for spacing of traces etc in the CAD software and it does some basic validation. (Are all the parts connected, not too close?).

I used KiCAD. It works well, though for assembly EasyEDA is probably lower friction. I had to dig around to find the right footprints for certain parts.

brudgers9• 8 months ago

Curious if there are meaningful differences between JLBPCB and PCBway.

solfox2• 8 months ago

Looks amazing! Reminds me of a funny reddit thread about a man who built a fiber optic star ceiling for his daughter. The top comment was "First child?". :)

https://www.reddit.com/r/DIY/comments/8g8pce/fiberoptic_star...

Brajeshwar2• 8 months ago

And then the things you do to redeem your guilt for the second child is a whole interesting area.

random_moonwalk16• 8 months ago

That's what the drum machine module is for.

sroussey• 8 months ago

And then they give up by the fourth. Guess which one I was, lol.

Bengalilol2• 8 months ago

Hi Brajeshwar (back to the old flashcoders days). Children grow up and in the end you get the full orchestra ^^

solfox2• 8 months ago

When I first saw the starfield post, I had one kid. I was building her all sorts of cool stuff: brio table, custom childrens book, etc. So naturally, I disbelieved the assertion that my second child would get anything less than my first. Alas, the insight is spot on - for all your good intentions, the second child gets shafted. I think it's just one of those things you have to experience to get it.

gwbas1c2• 8 months ago

Don't assume: Could be an only child, or the spouse is stay-at-home, or the author has family wealth and doesn't need a full time job.

prodigycorp• 8 months ago

could also be the first child ;)

giancarlostoro2• 8 months ago

or literally none of those options

hnlmorg• 8 months ago

I do get your sentiment, but you could have picked some better examples:

Could be an only child

In which case, odds are that they're also the first child ;)

or the spouse is stay-at-home

Which is a full-time job in itself

or the author has family wealth and doesn't need a full time job.

which is far far less likely than the assumption you're rebuttelling

fny• 8 months ago

Great work! This brings back memories of futzing with knobs on a boombox as a kid.

For your sake, I hope you built a heaphone jack.

random_moonwalk16• 8 months ago

Thank you! Unfortunately I decided to save that feature for v2!

gus_massa• 8 months ago

Strong sugestión for v2: Add a hidden knob to regulate the max volume. Kids love to raise it to the max.

(In a tablet, I had to secretly add some transparent tape between the speaker and the plastic cover case.)

gulan28• 8 months ago

This is awesome. I had vibecoded something similar called https://chippytune.com for myself. Still working on wav support though

habosa• 8 months ago

This is fantastic, as a hardware synth lover and a dad you’re making me pretty jealous.

ronbenton• 8 months ago

Wow looks professional

fainpul2• 8 months ago

A 3D-printed enclosure is fine for a prototype, but a real product likely needs injection-molded parts, which require expensive tooling.

For kid-friendly toys, yes. But for older users not necessarily:

https://teenage.engineering/products/po

speedgoose2• 8 months ago

I have two of those. They are great additions to my drawers.

One has a silicon case and is nicer to use though.

NoSalt3• 8 months ago

You say "they are great additions to my drawers". Is that because they suck, or is it that you don't have the time to enjoy them? (which I totally understand) I have seen these before and didn't know if they were worth the money. What is your opinion on them?

elric• 8 months ago

Wood is also pretty child friendly.

But neither injection molding nor carpentry will protect a synth from a child dunking it in a puddle of water.

analog31• 8 months ago

That's what backing up the design is for. ;-)

smj-edison• 8 months ago

Isn't there some kind of water proofing spray you can put on the circuits? I guess you'd still need some way to protect the batteries, but I think it is doable.

eimrine• 8 months ago

The spare board will solve this.

NoSalt3• 8 months ago

How are these, are they worth the money? I have seen these before, but thought they might be crappy "jokes". However, if they are decent, I would love to play around with them.

mlyle• 8 months ago

They -are- decent modular chunks. They have a bit of opinion pushing you in certain directions as far as sound goes.

Each one does a pretty limited set of things and combining them can be annoying.

But you get a lot for the money you spend on them.

mock-possum• 8 months ago

It’s pretty capable hardware, but in my personal opinion the UI sucks. It falls into the category of “why did you make this hard on purpose” and I resent it.

levicole• 8 months ago

I have a friend that writes lots of music on the PO-33. They are fun, definitely toyish, but you can get good results:

https://www.youtube.com/watch?v=TBo8Rd7HxdU <- a friend that creates a lot of music on small "affordable" pieces of gear.

brudgers9• 8 months ago

[context: I have eBay’d a couple of Pocket Operators because I was curious and the price was low enough I knew I could at least break even reselling on Reverb even after fees and shipping…This is how I rationalize my gas.]

Maybe buy one and if it is not for you be ok reselling it at a loss…framing it as renting an instrument helps me.

The Pocket Operators are musical and inexpensive for musical instruments.

Like any musical instrument practice hours are how you get amazing results and whether the instrument gels with you is the biggest influence of whether you put in the hours.

For me, the Pocket Operators haven’t gelled…I just don’t enjoy them enough to put in the time. But other people find them great and I can see why (not-for-me != bad).

_vqpz• 8 months ago

They're definitely very capable but limited machines, I enjoyed mine a lot until the potentiometers started thinking there was a change in the degrees even when I wasn't moving them

dimatura3• 8 months ago

"worth the money" is hard to say, especially for devices like these where the value is not really so much on the plain features as much as a more subjective factors like the design and the UI. I would say that purely based on features - probably not, especially with post-covid pricing. There are more powerful iphone or android apps for much less. Behringer, and to some degree Korg and Roland offer lower-end devices for not much more that ultimately might be more useful and usable. But, I do own a couple of these little guys and they're fun. I wouldn't call them "jokes", but calling them "toys" - in the good and bad sense - would probably not be a stretch, even if you can get some nice sounds out of them. I used to keep a couple on my desk and just jam a little with them as a distraction.

bigiain6• 8 months ago

I have 3. I have never regretted a single cent of what I paid. I don't get them out and play often, but even the fun I had when they were new was 10 times better value in the dollars per hour of fun measurement that most other things.

(If you happen to be in Sydney Australia, reach out, I'd happily lend you mine for a few weeks if you want to try them and see if the novelty wears off too quickly to spend the money yourself.)

moron4hire2• 8 months ago

They make cool sounds but their interfaces are so wonky I find them nearly impossible to do anything coherent, or even be confident I've fully explored the features. Imagine trying to program a VCR to make music. For as much as Teenage Engineering's visual designs are amazing, their functional interface designs are crap.

kentbrew• 8 months ago

Maybe consider vacuforming?

https://www.instructables.com/Vacuum-Forming-for-Free/

gwbas1c2• 8 months ago

Makes me wonder what the difference, in definition, is between a sequencer and a synthesizer? Is this really a synthesizer, or is it really a sequencer?

Yes, I'm splitting hairs about semantics.

PaulDavisThe1st• 8 months ago

The answer to your question is "yes".

It is a synthesiser AND it is a step sequencer.

dave_sid• 8 months ago

Both

butlike• 8 months ago

A sequencer is always in steps. A synthesizer has a signal generator and can modulate a single step. This toy is both a synthesizer and a sequencer, but since you cannot toggle the 4 steps off, it will always be a sequencer in addition to the synthesizer

oidar• 8 months ago

The linked project is both. A synth makes sounds, and a sequencer controls the sound over time usually with note on/off data. This sequencer has 4 steps before looping back to the beginning. To simplify, think of a sequencer as the music box drum and the synth as the tines in a music box.

strogonoff• 8 months ago

A synthesizer is generally a higher-level ready-to-use product containing any number of oscillators, sequencers, and other circuits and bells and whistles under the hood. A device with an oscillator and a sequencer qualifies as a basic synth.

At a lower levels you find modules like sequencer, oscillator, etc. They are generally not used by themselves: you plug a sequencer into an oscillator to make use of it, just like a standalone oscillator by itself simply makes a continuous noise that gets old quickly. A synth does that connection for you and exposes the controls.

(To make things even more fun, the lines between lower-level audio modules are often blurred. For example, the difference between a sequencer and an oscillator can be best summed up as: the former is commonly designed for unipolar control rate signal change where you can specify exact level per step, while the latter is designed for bipolar audio rate signal change between two predetermined extremes—however, as the “designed for” hints, you could configure some sequencers to output a bipolar signal changing so fast it is audible, just like you could run a square wave oscillator so slowly that it becomes a 2-step sequencer.)

phplovesong• 8 months ago

As a father to a daughter this warms my heart. Well done daddy! Points to you!

NickC25• 8 months ago

that's great! may your daughter make great use of it!

love the fact that your step sequencer even has a display to tell you what note you are adjusting to and from. i've always found that tuning synths and sequencers both analog and digital can be a pain because you can forget the note (or you don't have a good set of ears or perfect pitch) even if the result sounds good.

binary132• 8 months ago

Totally rad! Makes me think about what kind of simple programming could be possible with a minimal HCI like this.

tapland• 8 months ago

This is great. I’m going to start making something like this, but with some cut apple wood knobs, for my birds.

bitwize• 8 months ago

The other day I came across a post on Facebook that was just some guy grousing that the new Teenage Engineering gadget looked like "a baby's activity center". And now we've come full circle: a baby's activity center that's actually not far off from Teenage Engineering kit.

afandian4• 8 months ago

Amazing the things we do for our little ones. I built a toddler-friendly keyboard for my son. He's still playing some form of piano 6 years later, no longer with his fists or feet.

https://blog.afandian.com/2019/09/ux-for-toddlers/

newtwilly• 8 months ago

Beautifully done!

beAbU3• 8 months ago

Thank you for that closing paragraph in your article. Every time I read something online that tries to bend it into some "profound" lesson, or integrate it into the writer's personal brand, I throw up a little. This is most egregious on LinkedIn, and why I avoid that place unless I have to find a new job or something.

danvoell• 8 months ago

This is awesome. Just awesome. Love that it looks like a baby toy and packs enough punch to get a kid about 20 years up the line of music understanding.

cjonas2• 8 months ago

I've been learning CAD, 3d printing, PCB design and brushing up on my embedded programming... all with the goal of being able to build toys for/with my son. It's incredible how accessible it is in todays world, made possible by these advancements:

- incredibly powerful and cheap microprocessors (esp-32) - Fast, high precision desktop 3d printers - Affordable small batch PCB manufacturing - LLM's to advise on circuit design and help with embedded programming

Would you have any interest selling a non-comm license to the PCB, f3d files and source code? My 1.5yo son would absolutely love this!

mcrider• 8 months ago

Same, I recently got into Arduino so i could build a toy idea I had for my kid (a sort of "keepy-uppy" paddle game). I've always avoided Arduino projects because I don't like to code in my spare time (its my day job) and also learning how to wire things seemed daunting -- LLMs solved both of those problems for me (Claude's wiring tutorials are awesome and the code is simple enough that it can one-shot it).

I also bought a Bambu A1 3D Printer and it is unexpectedly way more fun and useful than I thought it would be. I designed the toy in TinkerCAD and it printed out beautifully (I also have been printing out lots of other toys and yes, useful things for around the house and for other projects).

Next steps are learning Fusion 360 and figuring out PCBs -- That also seemed daunting to me but its nice to see other amateur hobbyists are seemingly picking it up with not much difficulty.

cjonas2• 8 months ago

I highly recommend the "learn fusion 360 in 20 days" series on YouTube. I think I did it pretty causally in half that time. Then just find excuses to design stuff. After about a year of random projects, I can pretty proficiency draw most simple assemblies. This morning my son broke the battery hatch on his favorite toy and within an hour I had a replacement printed. (ducktape would have certainly been faster but where's the fun in that ;)

One thing I would point out is if your interested in organic shapes that blender is the better tool to learn/use. Fusions surface modeling is pretty hard to work with.

JoeDaDude• 8 months ago

Cool! Reminds of the Music From Outer Space synth in which the designer makes the claim that it "can actually get a child away from a television" and includes a video to prove it.

https://www.youtube.com/watch?v=i6M_KrZByz4

MFOS Weird Sound Generator

https://musicfromouterspace.com/index.php?CATPARTNO=WSG001&P...

thenthenthen2• 8 months ago

Looks so nice! The sam is a midi synth chip right? Super cool. How/where did you get the knobs?

random_moonwalk16• 8 months ago

Thanks! Yes it's a little digital synth that receives MIDI.

I used Chroma Cap knobs: https://store.djtechtools.com/products/chroma-caps-knobs-and...

thenthenthen2• 8 months ago

Aah kool, i had one in a arduino format board, was great to cycle through all the instruments randomly + some sequence/chords. Instant Aphex Twin

oldestofsports• 8 months ago

This is very impressive, it looks great!

BigTTYGothGF• 8 months ago

The traditional approach is you give noisemaking toys to your niblings, not your own children.

random_moonwalk16• 8 months ago

This sounds like a lesson I’m going to be learning the hard way

brudgers9• 8 months ago

Good parenting is doing things the hard way.

So why not go all in with a full set of acoustic drums?

beAbU3• 8 months ago

We've been following this. Every nibling or even the offspring of friends received xylophones, tin whistles, hand drums etc.

As long as it's not battery powered, it was on our "approved" list.

They love us (the kids. The parents... not so much I guess).

We have our first one due in a couple of weeks, and I guess we'll prepare ourselves for retribution!

warrenmiller• 8 months ago

is it feasible to built one with a PCB? just straight to the UNO like your initial prototype - did that work ok?

NoSalt3• 8 months ago

This is absolutely FANTASTIC, and I am humbled by your mad skillz!

My son and I are also fascinated by the sweet, sweet synth sound, but as I have no discernible talent, we went this route:

https://www.sweetwater.com/store/detail/Nts1Mk2--korg-nutekt...

Which, unfortunately, has a HUGE learning curve in terms of operation.

rcarmo• 8 months ago

This is great. I did a similar thing when my kids were young (revived an old, dead Kawai synth with a Raspberry Pi and sound fonts), but doing it with semi-discrete circuits seems a lot more fun.

broast• 8 months ago

So cool, I think all kids would love this

bbhi• 8 months ago

Looks like a fun project. I can highly recommend Teensy Audio Library for audio projects: https://www.pjrc.com/teensy/td_libs_Audio.html

gregsadetsky• 8 months ago

Mozzi (for Arduino) is also great!

https://sensorium.github.io/Mozzi/

simgt• 8 months ago

As someone who has never 3d printed anything, I'm surprised by how clean the case looks as opposed to what we usually see. Why is it so smooth?

TheSilva• 8 months ago

Sanding and polishing, likely.

bvm• 8 months ago

Nah, it just came out like that (i printed it :D)

We experimented with ironing, but you can't see it in those views. The A1 is a pretty good printer OOTB. There were a few iterations on the case design though to optimise the edges.

gpm• 8 months ago

The surfaces you're seeing in the pictures are almost all the "bottom" surface that was printed directly on the build plate. It basically just picks up the texture of the build plate and is otherwise smooth. That's actually a fairly bumpy build plate they printed it on (which lots of people like for aesthetic reasons).

That said modern 3D printers are good at producing pretty nice parts these days, especially if you print with small layer heights. You might be underestimating the possible quality of 3d printed objects.

sgallant• 8 months ago

My kids would love this.

woolion• 8 months ago

Were you aware of the Dato Duo (https://dato.mu/)? It's very cool for kids, except for the fairly steep price point.

The advantage is that it's limited, so it greatly reduces the wall of difficulty to manage to get some 'nice-sounding' music (mostly the restriction to the pentatonic scale). However, kids still manage to find the most horrible-sounding settings, and insist on keeping them as is...

helsontaveras18• 8 months ago

Wow, what an amazing demo for such a simple synth. Great work! If you ever start a Kickstarter, I’d be happy to donate. If it inspires some kid out there to get into music production, it’s a win for me :)

giancarlostoro2• 8 months ago

Would love something like this for my daughter, but with a max volume option she can't tamper with LOL

bigiain6• 8 months ago

That's a great reason to redesign it around an ESP32. So you can have an app on your phone that lets you control the volume over WiFi...

RobertWesner• 8 months ago

I can't put into words how awesome this is. Perfect demo.

PaulHoule• 8 months ago

Kinda funny but my adult son has taken an interest in guitars and keyboard and that has me working on MIDI routers with AVR-8 and building an ESP32 based synth module.

yzydserd• 8 months ago

I was too fascinated by the different thumb nail lengths to concentrate much on the video.

random_moonwalk16• 8 months ago

I trained as a classical guitarist, so I maintain some longer nails on my right hand :)

rock_artist• 8 months ago

What I love about this is how physical it is. So yeah, there's some board running DSP. but the design is amazing. It really relates to some recent posts also in HN about many objects loosing their physical UX. from an age of having buttons and tactical interfaces, everything became more touch based / app based which indeed cut price and allows easier updating. but also lacks some romance which is exactly what this device shows.

brudgers9• 8 months ago

Reminded me of a BlipBlox…

https://blipblox.com

bigiain6• 8 months ago

Reminded me of Teenage Engineering's Pocket Operators:

https://teenage.engineering/store/pocket-operators

I have a few of those, and heaps of my friends gat sucked deeply into playing with them at the expense of whatever they actually came over for. "Nah, I'm not hungry. You should all eat without me, I'll just finish tweaking this groove."

They're aimed (as the company name hints) as a little older than 3 year olds.

One hint for the OP, it's so cool how you can plug those toys into each other in a chain, and have them all sync - so the percussion, base, and melody can all be programmed on threee different POs, and automatically play together.

throwaway675309• 8 months ago

Agreed. That's half the reason that no matter how accurate a virtual synthesizer can be (like the Mac App Moog Model D), there's just no substitute for being able to physically fiddle the knobs and dials.

mttch• 8 months ago

This is great, i’d kickstart it, my 5 year old would love it.

Krisso• 8 months ago

Dad of the year <3

tmilard• 8 months ago

I'm not a kid. I still want it !

pragma_x2• 8 months ago

Same. It's a solid four-note ARP that sticks to a fixed set of musical keys. You literally can't make bad sounding music with this.

A more grown-up version of this would be 16 notes, with variable length patterns (4-16?), and a "swing" function. A little bit of I/O mux under the hood and I bet this design could be expanded in that way. Or maybe you just daisy-chain multiple sequencers?

brudgers9• 8 months ago

This ends at Eurorack.

chaosprint• 8 months ago

Great finish. I was busy designing and soldering the prototype synthesizer during the summer, but I had to put it on hold because my baby was born in September.

I had the same problem back then: injection molding is quite expensive to start. But you could consider a more creative approach: using a PCB directly as the panel, such as a TE's Pocket Operator. Korg also has this solution for some educational products. Alternatively, you could use 3D printing; there are many inexpensive services in China. CNC doesn't have the mold-making issue, but it's more expensive and doesn't seem suitable for children.

Another interesting point: after my child was born, I didn't have much time for my sound work. But recently, I was surprised to find that I spend most of my time playing white noise on Glicol (http://glicol.org/) and it works great for my kid.

``` o: noise 42 >> lpf ~mod 1 >> mul ~mod3

~mod: sin ~mod2 >> mul 200 >> add 1000

~mod2: sin 0.1 >> mul 0.04 >> add 0.1

~mod3: sin 0.04 >> mul 0.3 >> add 0.8 ```

Good luck with kickstarter!

Joeboy2• 8 months ago

It's not kid friendly, but in case anybody's interested I just wrote up how I made a simple "hardware" synth by bodging together a Raspberry Pi Pico 2 and I2S audio module, total cost around £10 on Amazon UK.

The hardware's very cheap and easy. The "default" synthesis is pretty simple but also pretty hackable (in Rust) if you want to customize it.

https://github.com/Joeboy/oxynth/

afandian4• 8 months ago

Thanks for sharing!

I did some similar playing around with an ESP32 and I2S a few years ago (lockdowns were an odd time). Where I seem to remember getting stuck was how to get the phase to line up, so that each sample looped at a zero-crossing point (which is different for each frequency).

For the lazy, what did you do?

https://gitlab.com/afandian/melodicornamuse/-/blob/main/melo...

Joeboy2• 8 months ago

I don't really understand your issue sorry, but my thing basically just writes the audio output to a buffer, and the DMA and PIO "automatically" send that to the I2S output. There's also some messing about with ping ponging between two DMA buffers to avoid gaps between each buffer write audio. I guess things might be quite different on the ESP32.

Edit: Ok I glanced at your code, if I read it right it seems like you're writing sin waves into buffers at "init" time then copying the appropriate buffer at "run" time. Which is not what I'd do, but then I'm used to more luxurious devices. Maybe try using a fast sin approximation rather than the precomputed buffer table?

https://bmtechjournal.wordpress.com/2020/05/27/super-fast-qu... might be helpful there.

dimatura3• 8 months ago

were you using single cycle waveforms or longer samples? in the former case, I guess there's not much to it, you just cycle through the waveform (in which case the waveform you choose would usually start and end at a zero crossing by construction, like sines, triangles, etc - or, if it does not, well, that will just create extra harmonics that might or not be desirable). For the second case, it's more subtle. Most samplers that implement this feature will assume correct loop points (usually, but not necessarily at a zero crossing) are chosen manually by the user. Some of them implement cross-fading at the looping point to make that more forgiving, but that may be CPU/RAM intensive for some devices. If you're referring to small clicks you may get at the start and stop of sample playback, it's fairly common to use very short (ms or less) fade-in/fade-out to avoid that. There's a lot of books out there, but the main one I've read and enjoyed is this one, that happens to be free: https://cs.gmu.edu/~sean/book/synthesis/. it's more of a textbook than a cookbook.

dep_b• 8 months ago

The korg monotribe is magic for kids

rmnclmnt• 8 months ago

Your daughter is so lucky! I meaning the physical UX is very reminiscent of teenage engineering, looks great! The more I was scrolling down the article the more I hoped for an « order » button :)

random_moonwalk16• 8 months ago

Thanks for all the kind words and feedback. There are some comments expressing interest in supporting a Kickstarter etc. If you're interested in receiving updates you can leave your email here:

https://tally.so/r/Y55dXv

Thanks again - this was a bit of a surprise!

jbl0ndie• 8 months ago

Lovely project and a really great idea.

Have you come across soft tooling for injection moulding? It's a lower cost, short run approach using much less durable moulds from various materials.

random_moonwalk16• 8 months ago

Thank you!

I didn't know that was a thing - I'm going to look into it.

jacquesm2• 8 months ago

Before you have that working you'll have 3D printed a containerload of these ;)

Besides the lack of flexibility if you want to make changes. I've used soft tooling for some projects but I was (1) never really happy with the results and (2) ended up breaking the molds quite often resulting in a lot of wasted material and expense. 3D printing is the way to go for projects such as these.

MrsPeaches• 8 months ago

It’s a great project!

I’ve got some experience with small batch production and I’ve written an email. Check your spam!

random_moonwalk16• 8 months ago

Thanks, I've responded :)

NobodyNada2• 8 months ago

That is fantastic, I love it!

If I may submit an extremely pedantic music nerd bug report: at 46s in the video demo (https://www.youtube.com/watch?v=qboig3a0YS0&t=46s), the display should read Bb instead of A#, as the key of C minor is written with flats :)

(The precise rule is that a diatonic scale must use each letter name for exactly one note, e.g. you can't have both G and G# in the same key, and you can't skip B. This has many important properties that make music easier to read and reason about, such as allowing written music to specify "all the E's, A's, and B's are flat" once at the start of the piece instead of having to clutter the page with redundant sharps or flats everywhere.)

nine_k• 8 months ago

The device is fantastic indeed!

Regarding flats and sharps: one could ignore the Pythagorean stuff and go full well-tempered dodecaphonic, thinking purely in terms of semitones in the intervals. This toy sort of nudges towards this. It would be fun to add 12 small LEDs along the faders, and show the number of semitones with them, relative to the previous fader's position.

On one hand, the fact that the same sound can be named A# and Bb may be puzzling for a kid (they could differ on a violin, I suppose); OTOH if the kid later learns formal music notation, this becomes helpful, so your comment holds.

hunter2_• 8 months ago

If only the users contributing chord charts to sites like Ultimate Guitar understood this; the number of times I've seen this wrong is astounding. For example, a progression like I-iii-IV in the key of E major will be written as E-Abmin-A but ought to be E-G#min-A for the reason you stated: pratically it's confusing, theoretically it's wrong, and there's simply no upside at all.

Using exclusively sharps (or flats, but that's not so common) is for piano technicians, frequency-to-note calculators, and similar utilitarian situations that aren't in a diatonic context.

Aside: this is also an easy way to explain double sharps and double flats. If you stumble upon one, and decide to see what would happen if you eliminate it in favor of an enharmonic equivalent (i.e., a natural), you'd end up with a scale that uses some letter twice and also skips a letter. The double sharp/flat achieves the use of each letter exactly once. A bit cumbersome on most instruments (keyed instruments especially), but it does make for easier sight reading (vocals especially) when stepwise movement uses each line/space of the staff, rather than skipping.

jeffalyanak• 8 months ago

I'm pretty sure that NobodyNada knows this, but for pedants out there using Bb instead of A# is specifically a classical European music notation thing.

There's nothing wrong with using A# and plenty of other notations do. For a modern, hacker-y example, tracker notation only uses sharps).

tietjens• 8 months ago

This crosses such a rare line of being something that both children and adults would love to have around to play with. Even though I know you didn’t build it to be a product.

Nition• 8 months ago

If you ever did this as a larger Kickstarter type project, I wonder if it'd be possible to get stepped faders so you could physically click-click-click-click through each semitone.

random_moonwalk16• 8 months ago

This is a cool idea, but you can switch between major, minor, chromatic and pentatonic scales so the interval between notes changes depending on how many there are so having fixed clicks wouldn't work in that case.

the_arun• 8 months ago

Great project! What I liked most is how you credited every individual along the way in the article. That shows how authentic you are. Kudos!

LooseMarmoset• 8 months ago

This is an absolutely fantastic piece of work! You deserve a round of kudos and kind words.

peteforde• 8 months ago

Great work on this.

One thing I haven't seen in the comments so far is any comment about the knobs and sliders. The young kids I know take perverse delight in pulling off knobs and throwing them. Make sure that they are glued down!

redbell• 8 months ago

this was a bit of a surprise!

That's one of the coolest parts of HN! This post was posted five days ago and went totally unnoticed by the community, probably, even OP has forgotten about it. Thankfully, HN had what is called Second Chance (https://news.ycombinator.com/item?id=26998308) and since this post is a masterclass in building a physical product, the mods decided to bring it back by featuring it on the front page, where it finally got the attention it deserved. A true masterpiece indeed!

Dowwie2• 8 months ago

I don't want to buy one-- I want to build one! I already have a 3d printer and the electronic components.

markatkinson• 8 months ago

Boet you broke the internet! I can't subscribe to updates :(

random_moonwalk16• 8 months ago

Ah the Cloudflare outage has hit my form!

nixass• 8 months ago

Seems like interest for your synth brought down Cloudflare!

dinobones• 8 months ago

This is such a good idea!

Kids music toys are often just purely toys tap a button, make a sound... But the skill ceiling could be so much higher, offering the ability to learn and express themselves more. Awesome work.

amenghra• 8 months ago

One of my favorite kids music toy is a mini piano where you have to replay one among 5-6 melodies (each melody is 5-10 notes that you have to memorize by ear — no lights involved) to unlock a little happy sound. This toy managed to keep both, dad and kid busy for a while.

moron4hire2• 8 months ago

For anyone who likes the idea of better music "toys" for their kids (i.e. not toys at all, but still easy to use) but doesn't have the capacity to build stuff like this, my kids and I love the Korg Koassilator: https://www.korg.com/us/products/dj/kaossilator2/

You can usually get them on eBay for USD$60 - 70. You do need to bring your own speakers, but a pair of cheap PC speakers are good enough, and it's a good start on creating a whole synth + effects chain.

Speaking of which, there is also the Mini Kaos Pad, which is a dynamic effects processor: https://www.korg.com/us/products/dj/mini_kaoss_pad2/

This one is a little more difficult to figure out for the kids as it is a "modifier" in the chain and they haven't quite wrapped their head around that concept yet. But still, it works great, has lots of features, and is really inexpensive for such a thing.

And finally, they have a number of these mini-synths that are in the USD$30 - 50 range that are a ton of fun: https://www.korg.com/us/products/dj/monotron_duo/

TurkishPoptart• 8 months ago

Good lord, you must have an amazing wife/support system to give you some peace while you designed this amazing toy.

random_moonwalk16• 8 months ago

I am very lucky in this regard, my partner is amazing indeed! Most of the work was at night, so I hopefully didn't disrupt her too much.

fabioq• 8 months ago

What an incredible idea, I with every nursery to school had some of these!

ty_2k• 8 months ago

Really cool project, super polished. The panda animation!

yigalirani• 8 months ago

build it at scale and make a fortune

jeremydavid• 8 months ago

Wow! Very cool. How hard would it be to create a "custom" sound, where you use the sliders to adjust the Attack Decay Sustain and Release?

evmaki• 8 months ago

What a beautiful and charming project. Kudos for taking it all the way from zero to one with such a polished design. That's no small feat. I've built prototypes for eurorack and even with some simplifying constraints it's a lot of work.

Best of luck with your Kickstarter!

amatecha• 8 months ago

Ahh, this made me think of "Dato DUO", similar concept (though the Dato stuff is a little more complex): https://dato.mu/

Bengalilol2• 8 months ago

I love the atmosphere, the object and the purpose.

mft_• 8 months ago

Hmm, very cool project and maybe just the inspiration I need.

I bought a Baby Einstein Magic Touch Guitar for a friend’s daughter a couple of years ago, and while it was okay as a toy, it was disappointing as a musical instrument because the chords it plays are badly chosen. It’s basically impossible to play along with most songs.

I’ve had the back burnered idea to buy another and improve it; maybe I will now, following a variation on your approach.

thomasqbrady• 8 months ago

This is phenomenal, but my biggest question is (which is probably a more of a long-term one that comes from genuine curiosity/fascination, not doubt): does she use it/enjoy it? I'm so curious to see what happens over time. Does she learn the functions of these buttons, years before having words for what they're doing? Does she write some music? Does she grow up expecting things with knobs to be this interactive/creative? SO cool!

blauditore• 8 months ago

3-year-olds actually have quite a vocabulary, so they can certainly talk about what the knobs are doing, maybe just not as accurately as adults.

Regarding discovering functionality: The author mentions Montessori stuff, and the philosophy there is unguided discovery, "let them figure out by themselves". Not sure if that's how the author is planning to use this too, though.

nielsbot• 8 months ago

Reminds me of the work of Love Hultén: https://www.lovehulten.com

He builds beautiful, colorful, retro-futuristic audio-visual art pieces Many are synths.

dimatura3• 8 months ago

There's a fun podcast by Arman Bohn/Distropolis (who himself has made some cool small-batch hardware synths) where he interviews makers of small hardware synths, https://open.spotify.com/show/30USGHPeGQ9ZyWQDyRnfcv might be of interest.

sunray2• 8 months ago

Putting aside the beauty of both the synth and its purpose, what I'm curious about is the learning process in making this. The running theme is that you picked up several new skills 'from cold'. That in itself is impressive enough. How did you approach learning:

- the necessary basic electronics;

- PCB design;

- 3D CAD;

- your particular iterative process,

among other things? I get the impression you built things incrementally, observed what happens and learnt via that feedback loop? Maybe others could share their own feedback loops, too.

random_moonwalk16• 8 months ago

I've been reflecting on this a bit. I found it very useful to have a well-defined project and focus the learning time on things that are necessary for completing it. Having a background in coding was useful because I find you end up developing a knack for isolating parts of systems and figuring out how to work on small parts that end up fitting together.

I therefore focused initially on simply getting readings from a single potentiometer; if I could do that then I felt pretty confident I could read from four of them. If I could generate a midi message I was pretty confident I could send it to something that could read it etc.

When I started on the PCB design I had a simple circuit already so it was a case of translating that onto a board.

I didn't get too deep into any of the various parts but I found that it gave me a birds-eye view of the whole process and I now feel confident in isolating parts of them and 'zooming in' to them and refining them, building on the foundation I've developed.

endorphine• 8 months ago

Where would you suggest someone starts for building something like this.

What kind of hardware would you suggest (preferably something with Rust!bindings). Is the one used in the original post a good starting point?

I've minimal to no experience with embedded.

evereverever• 8 months ago

Amazing! Kids need more synths! My kids play the blip blop and the critter & guitari synth.

michaelhoney• 8 months ago

So impressed by this, from someone with no prior experience. A1 hacker news experience, congrats

Geste• 8 months ago

Oof, nice one !

I was looking for some synths for my less-than-two-years kid, after seeing their face light up when I fiddle with my Lofi 12 XT in front of them.

I had all these criterias : -Something without any screens -Something simple enough -Something that could withstand some rough play

I looked and looked, was considering proper Aira Compact synths, but ended up with the antiquity of the Bliptronic 5000 from Thinkgeek. https://youtu.be/6rCfhF-fNb4 They love it, the buttons are beyond fun to them, but the knobs are quite hard to turn for a little kid (1st world problem, I know)

I felt they were too young for a Blipbox, and I also bought an Orba 2, we'll see how that one goes.

But I dreamed of such a device, with easy to turn knobs, and colorful display, something simple to modulate sounds and just hear melodies. Seeing how you created it is both inspiring and discouraging, as someone with limited free time and electrical knowledge, but, you never know !

freshnode• 8 months ago

Well done. This is really inspiring.

_adamb• 8 months ago

As a EE nerd, I love this project. As a parent, it's the sort of toy I want to smash as the repetition drives me insane.

What should I make that captures the awesomeness of this project without the insanity? Hmm...

findthebug• 8 months ago

love this!

beAbU3• 8 months ago

I want to commend you for making this actually musical. Too often these basic synths aimed at kids are little more than a noise maker unless you really know what you are doing.

My spouse and I are into music and we are pretty serious choristers. We have our first little one on the way this December, and we definitely want to expose them to making music from a very young age. Your synth looks like an excellent way to do that, as it does not seem possible to get it in a state where it's just making horrible noises, every state will be some new pleasant little jingle.

Bravo!

johntash• 8 months ago

My mind jumped to synths from the Fallout games, so I was disappointed to find something else, but it's still pretty cool!

dazamarquez• 8 months ago

Is the plastic and other materials you used safe for children?

Dowwie2• 8 months ago

We have similar interests! I've been working on a DIY animatronic project that is mostly vibe-coded using Sonnet 4.5. It's my first electronics project. So far, I got the Ultrasonic Sensor to trigger led when object is less than 2 feet away. I set up a sound player and the components fried when I started the device. I have to redo all of the wiring for the sound setup again. I only have one of three sound modules that isn't bricked.

The comments in this thread reveal a community of parents who are aspiring builders of high tech devices for their children. I think this community need a discord.

jacquesm2• 8 months ago

There's a lot of talent on display here. For someone who has never done any of this I'm so impressed with the degree of finish and care as well as the functionality of the device. It even sounds pleasant. Dad of the year award!

Rioverde• 8 months ago

Just Amazing !

Show HN: I built a synth for my daughter

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