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Hardware projects

Making the chipophone

Håkan, organ donor.

It all started when a good friend of mine asked me if I wanted an old electronic organ. He had bought it in a thrift store some years ago, but had now realized that it would remain untouched in his cellar forever unless he could find a new home for it. I accepted the gift on the condition that I could do whatever I wanted with it, in terms of modifications and experiments.

Let me clarify at this point that organs like these are not particularly rare. They were mass produced in the seventies, and most thrift stores in Sweden have at least one of them on display. As can be seen in the pictures below, they are based on solid state technology (transistors), but not integrated circuits.

The organ was in good condition, with only a few contact glitches in the pedals and switches. It featured a set of really plain organ patches, tremolo, reverb and volume controls.

Reverse engineering

The first step was to remove the back cover. An overwhelming amount of dust was eager to come out and see the world, having been locked up for all those years.

It's always a pleasure to work with old machines that have been designed with maintenance in mind: As you can see from the pictures, there were several hinges and other details to aid the repairman.

The bottom right of these images shows a spring reverb tank, similar to what you'd find in a guitar amplifier. This makes sense because reverb, as I've discovered earlier, is the key to synthesizing organ-like sounds.

The reverb tank is currently not used in the chipophone, but it might be integrated in the future.

Apart from the reverb, there's a huge loudspeaker, a transformer, capacitors for the transformer, and rows upon rows of switches and wires. And then there are twelve oscillator cards:

Oscillator card

This struck me as odd at the time, because it seemed like a really backwards way of design a synthesizer, but I suppose it made perfect sense in the analogue world.

There are twelve oscillators, one for each semitone. Each tone is divided down into several versions at different octaves. Then, if I'm not mistaken, these oscillating waveforms are attenuated according to a set of volume signals (presumably voltages or currents) arriving from the keys themselves. Every key acts as two or even three physical switches, feeding the volume signals from a few master signals that are controlled using the switches and knobs on the front panel. So, for instance, the volume signal for F#, second octave, might be a weighted sum of the first overtone of the second F# of the upper manual, and the second overtone of the first F# of the lower manual. Think of it as electronics simulating air flowing through ducts and hoses.

Making a MIDI keyboard

After some deliberation, I began cutting the wires. There was no turning back now.

Bank of switches

I had decided to modify the organ into a MIDI keyboard. To do that I just needed a single switch for every key, so a lot of the wires could simply be removed.

The remaining wires were connected to a bunch of 74HC165 chips, 8-bit parallel input latches that can be daisy chained into a single serial line. Two sets of 44 keys, 13 pedals and a couple of switches made for a total of 120 input signals and a daisy chain of 15 chips.

The daisy chain is controlled by an ATmega88 microcontroller, which is responsible for polling all the signals and running a debounce algorithm. The microcontroller also has six analogue inputs, which are directly connected to the five potentiometers on the front panel (the leftmost knob is a switch) and the right foot pedal.

The pedal

The analogue pedal, used as a volume controller in the original design, was not a potentiometer. This came as quite a shock to me, but again, I suppose it made sense in the good old days of no op amps.

The pedal contained a small light bulb that would shine through an opening, the width of which would vary (non-linearly) as the pedal was operated. This would cause a varying amount of light to shine on a photoresistor on the other side of the opening. Rube Goldberg would've been proud. I do not know whether the lamp was designed to shine with a constant light intensity or if it would actually carry an audio signal.

I replaced the light bulb with a high intensity LED.

The synthesizer

Once the MIDI keyboard was up and running (thoroughly tested with a General MIDI softsynth of course), I started experimenting with creating an ATmega88 based synthesizer with typical chiptune sounds. I could re-use code from several earlier projects, of course.

The synthesizer contains eight independent waveform generators capable of generating pulse waves, lo-fi triangle waves and white noise, as well as some experimental features like ring modulation. These eight voices are then allocated dynamically as keys are pressed. Please refer to the chipophone page for further details.

The linear bits

The original electronic organ contained its own amplifier and loudspeaker. I've opted for a traditional line out signal for the time being, so external amplification is necessary. This also enables me to power the chipophone from a single 5V supply.

In the future, I hope to incorporate the loudspeaker and reverb tank back into the chipophone, but then I'm going to need op amps and a dual power supply to drive them. Time will tell if I ever get around to doing this, but it bugs me that I have a perfectly good spring reverb tank just laying around.

Posted Wednesday 21-Jul-2010 21:42

Discuss this page

Disclaimer: I am not responsible for what people (other than myself) write in the forums. Please report any abuse, such as insults, slander, spam and illegal material, and I will take appropriate actions. Don't feed the trolls.

Jag tar inget ansvar för det som skrivs i forumet, förutom mina egna inlägg. Vänligen rapportera alla inlägg som bryter mot reglerna, så ska jag se vad jag kan göra. Som regelbrott räknas till exempel förolämpningar, förtal, spam och olagligt material. Mata inte trålarna.

Anonymous
Thu 22-Jul-2010 21:52
Sir, this is the most awesome thing of the day. You would rock at Comic Con!
Anonymous
Thu 22-Jul-2010 23:29
I am completely in love with the Chipophone! I neds one!
Anonymous
Fri 23-Jul-2010 00:02
How much would it cost to have you build me one?
Anonymous
Fri 23-Jul-2010 00:19
This is one of the coolest things I have ever seen, props to you man for having the initiative to actually go through with this conversion. Cheers
Anonymous
Fri 23-Jul-2010 03:15
holy fuck! this is good. very *very* good!
Anonymous
Fri 23-Jul-2010 04:48
Linus, Bravo! great project, beautiful job, Thanks for sharing. N3, Detroit Michigan, United States
Anonymous
Fri 23-Jul-2010 05:27
You are a genius!
Anonymous
Fri 23-Jul-2010 05:47
the thing you wrote about the pedal struck me as a very creative solution back in the days. friggin awesome to use photo sensitivity in this context. good to see the love you have for life, music, technology and with everything that you do. cheers!
Anonymous
Fri 23-Jul-2010 07:57
Well done man, seriously. Thank you for doing this. I would love to buy one if you ever start selling them. You stand to make a good amount of money I assume.
Anonymous
Fri 23-Jul-2010 08:14
AWESOME! Ge mig!
Anonymous
Fri 23-Jul-2010 08:46
AMAZING!!!
Anonymous
Fri 23-Jul-2010 08:54
You're my hero.
Anonymous
Fri 23-Jul-2010 08:57
ZSÍRADÉK! :)
Anonymous
Fri 23-Jul-2010 10:19
Wow! Very cool!
Anonymous
Fri 23-Jul-2010 10:44
Absolutely amazing! Looking forward to more video's!
Anonymous
Fri 23-Jul-2010 10:50
This is one of the coolest things I have ever seen, props to you man for having the initiative to actually go through with this conversion. Cheers
Anonymous
Fri 23-Jul-2010 11:06
This is the coolest shit ever! You, sir, are a gentleman and a scholar!
Anonymous
Fri 23-Jul-2010 12:16
your my nerd-idol!
Anonymous
Fri 23-Jul-2010 12:27
Totally awesome!
Anonymous
Fri 23-Jul-2010 13:07
YOU ROCK! Fantastic work! You, Sir, are truly a man for all seasons!
Anonymous
Fri 23-Jul-2010 13:20
I'm glad that a chip-tune enthusiast also appreciates the value of a good spring reverb!

Great job on this! Amazing to read about what you've done. I hope you write some original compositions for the Chipophone.
Anonymous
Fri 23-Jul-2010 13:48
This is truly amazing, You just made my day!

cheers from Iceland
Anonymous
Fri 23-Jul-2010 14:58
Great stuff! Seeing someone as talented in the technical way as in artistic measures makes me happy. Please keep on posting new music on youtube - you could even invite fellow scene musicians to do live-sets at your house, so you don´t have to do it all by yourself. I would love to see / hear zyron or fanta or... what about reyn?
Anonymous
Fri 23-Jul-2010 16:06
brilliant. absolutely brilliant.
Anonymous
Fri 23-Jul-2010 16:09
I would love to build the synth to use as a sound source. Are you planning to make schematics and source available? Or at least a pre-programmed AVR chip?
Anonymous
Fri 23-Jul-2010 16:36
Wonderful project! Congrats!

Regarding why they used the light bulb/photoresistor setup for the expression (volume) pedal - all electric organs at that time took at least some design inspiration from the original Hammond organs - the expression pedals in classic tonewheel Hammonds use an air-variable capacitor - the moving parts don't directly contact each other, which makes for a wonderfully quiet pedal (electronically & physically) that won't ever get scratchy. I'd bet the pedal in your organ was designed with that in mind - they may have found that pots available at the time weren't up to it.
Anonymous
Fri 23-Jul-2010 17:38
You, Sir, seem to be shitting with us. Want to tell us where that noise disappears to the time you supposedly play it yourself? Next time try a microphone which has a lot of noice if you record.
Anonymous
Fri 23-Jul-2010 17:39
hasn't*
lft
Linus Åkesson
Fri 23-Jul-2010 18:12
You, Sir, seem to be shitting with us. Want to tell us where that noise disappears to the time you supposedly play it yourself? Next time try a microphone which has a lot of noice if you record.

Sure, but several youtube commenters have already figured out the answer to this question independently, actually. =) The output from the chipophone was routed to a separate track, which was mixed in afterwards during editing. The volume of the speech track was lowered so the sound from my monitor speaker wouldn't interfere with the real track. It still does, if you listen carefully during the parts where I speak while the synthesizer is sounding.
Anonymous
Fri 23-Jul-2010 18:50
Highly impressive and very cool!
Anonymous
Fri 23-Jul-2010 19:33
Great work, impressive old tunes You played, congratulation!
Respect, Yozef from Hungary.
Anonymous
Fri 23-Jul-2010 20:35
Nicely done! I'm very impressed. Salt Lake City, USA
Anonymous
Fri 23-Jul-2010 20:46
Linus, you are the next Koji Kondo! (SMB music composer)
Anonymous
Fri 23-Jul-2010 22:49
Dude, when you played the commando highscore tune, i almost got tears in my eyes!
The chipophone is a piece of art, a tribute to old electronic games.
Well done!
Anonymous
Fri 23-Jul-2010 23:12
May you live for a thousand years.
Anonymous
Sat 24-Jul-2010 00:52
Super cool!
Anonymous
Sat 24-Jul-2010 01:37
"Håkan, organ donor." ..... (speechless)....
Anonymous
Sat 24-Jul-2010 02:21
BRILLIANT!!
Anonymous
Sat 24-Jul-2010 05:45
Fantastiskt!
Anonymous
Sat 24-Jul-2010 06:42
Solid work you got there. Maybe in the future you can get a small touch screen to replace all the switch controls.

d@@b
Anonymous
Sat 24-Jul-2010 08:42
Very sweet project. I've been playing around with R-2R ladder DAC's and they're getting really nasty on my breadboards when using the actual resistors ;). Could you possibly give a part# for that R-2R you're using? I'm having trouble finding one that's not surface mount.
Anonymous
Sat 24-Jul-2010 08:51
заебись!
Anonymous
Sat 24-Jul-2010 10:47
You made an awesome and unique work. This is really engineering art :)
Anonymous
Sat 24-Jul-2010 12:34
Awesome work can you please post details on instructables for DIY it will be a great DIY project.

Thanks.
Anonymous
Sat 24-Jul-2010 14:53
"organ donor" just cracked me up :)
//vanti
Anonymous
Sat 24-Jul-2010 17:44
In case you're curious, the volume pedal design with the light and photocell is still very common. No moving parts to wear out, you see. But it is nonlinear and requires analog support circuitry.

In the digital domain, you'd use some kind of quadrature encoder and process the pulses directly. But unless you can actuate it directly over the distance of pedal travel, you're going to have some kind of mechanical system to convert a dozen degrees of rotation or a couple of cm of travel into 256 MIDI values. Look for components which will tolerate a million cycles of use.
Anonymous
Sat 24-Jul-2010 18:15
So cool! Heard about it on Slashdot. Thanks for the fabulous demo!
From Maryland, USA
Anonymous
Sat 24-Jul-2010 18:20
good work my friend!
Anonymous
Sat 24-Jul-2010 18:33
Hey Linus! Go back to working on Linux damnit!
Anonymous
Sat 24-Jul-2010 18:59
This is the coolest shit ever! You, sir, are a gentleman and a scholar!
Anonymous
Sat 24-Jul-2010 20:41
As an old player piano and organ technician, I would have to say your abilities are to be admired. Well done!
Anonymous
Sun 25-Jul-2010 05:42
Tusen tack! Detta är skitbra!
Anonymous
Sun 25-Jul-2010 06:38
Dude, that was awesome. Especially the Mega Man music. I'd say those old Mega Man tunes influenced me so much as a kid that I now listen to electronic music regularly. Thanks for the video!
Anonymous
Sun 25-Jul-2010 10:42
I'm impressed! that's outstanding!
Anonymous
Sun 25-Jul-2010 11:31
Såg en youtube-länk på facebook där du demonstrerar Chipophonen. Bland det häftigaste jag sett på år och dag. Uppenbarligen är du såväl tekniskt som musikaliskt begåvad. Fortsätt gärna och posta videor där du spelar på den.

//Benny - Trollhättan
ralph
Ralph Corderoy
Sun 25-Jul-2010 11:50
A marvellous project, well done. And having arrived here from Slashdot I've now the wealth of the rest of your site to explore.

You mentioned the 120-bit shift register, how often do you sample all of its bits?
Anonymous
Sun 25-Jul-2010 12:43
UNDERBART, Linus! Ett litet hopp för mänskligheten har tänts i mitt bröst.
Anonymous
Sun 25-Jul-2010 13:49
Goodjob! Greets from Holland!
Anonymous
Sun 25-Jul-2010 17:15
You make a lot of people happy :) including me
Anonymous
Sun 25-Jul-2010 17:52
Very cool!
Anonymous
Sun 25-Jul-2010 22:26
Incredible! Greets from Hungary.
Anonymous
Mon 26-Jul-2010 02:21
Awesome work, and a enjoyable read. Thanks for writing this up. Great work, very inspiring.

Greets from Scotland.
Anonymous
Mon 26-Jul-2010 03:35
lovely work! it may be that I haven't looked around this website that much but do you have blueprints or schematics for the chipophone? I would love to have one!


Yours from the U.S.
Anonymous
Mon 26-Jul-2010 10:13
"Håkan, organ donor." ..... (speechless)....

I loved that one aswell :D
Anonymous
Mon 26-Jul-2010 19:15
You sir are a genius. I wish I had one. It's but another instrument that I really really want.
Anonymous
Tue 27-Jul-2010 03:15
As someone said, brilliant, absolutely brilliant work. I'm your fan.
Greetings from Brazil, from a 8-bit minded old man.
Anonymous
Tue 27-Jul-2010 06:29
Hearing your device has made my day. Thankyou, and I wish I had half your skill!
Anonymous
Tue 27-Jul-2010 17:12
Dude you almost made me cry. I always wondered how those songs were created. Thank you for a truly magnificent display of technical genius. That was truly the best thing I've seen on YouTube.
Anonymous
Tue 27-Jul-2010 18:24
Awesome project!
Anonymous
Tue 27-Jul-2010 20:26
Ja vad ska man säga ,, väcker många minnen från C64 tiden :).. helt klart det bästa jag sett på bra länge :)..
Anonymous
Tue 27-Jul-2010 21:14
Absolutely breathtaking...
Anonymous
Tue 27-Jul-2010 21:45
Wow, this is amazing! Dude, i was awestruck when i watched the video. I love sid tunes and you did an amazing job turning that organ into a fullblown sid-wonder!
Anonymous
Wed 28-Jul-2010 00:36
ah man this shit is wicked
Anonymous
Wed 28-Jul-2010 04:37
You are absolutely incredible! The designing of your chipophone
blew my mind. Not only that but your ability to play multiple NES
tracks from the old days is beyond impressive! Kudos to you, good
sir ~ you are an inspiration to us all, local & foreign.
Anonymous
Wed 28-Jul-2010 06:40
Wow!!!, i don´t have words! really, amazing!
Anonymous
Wed 28-Jul-2010 10:07
Have you ever hear the Sliver Surfer sound track for NES. May not the most complex music, but fun.
Anonymous
Wed 28-Jul-2010 11:03
i would also love to see a instructable online to convert my own electric organ into a midi 8-bit chiptune producer :P
Anonymous
Wed 28-Jul-2010 12:59
Ты крут чувак +100500
1й нах!!!!
Anonymous
Wed 28-Jul-2010 13:16
Awesome work, I love it!
Anonymous
Wed 28-Jul-2010 16:06
Cool man, keep up the good work, by the way very entertaining video...
Maisteri
Helsinki, Finland
Anonymous
Wed 28-Jul-2010 17:11
That's the coolest thing I've seen in ages! Nice work!! MattF
Anonymous
Wed 28-Jul-2010 18:31
May you live for a thousand years.
+1 we need more human beings like this on our planet.
Anonymous
Wed 28-Jul-2010 19:06
Fantastic! Great job!
Anonymous
Wed 28-Jul-2010 19:11
Great job! I think it's funny that you call your friend Haiku an "organ donor." Haha
Anonymous
Thu 29-Jul-2010 00:37
"Håkan, organ donor." ..... (speechless)....

I LOL'd at that as well- brilliantly deadpan (or, at least, that's how I read it!)

And this project is amazing. Thanks for the incredibly thorough breakdown, the inner workings of the original organ are fascinating (yes, particularly the photosensor-based pedal).

Incredible job! Thanks for sharing!
Anonymous
Thu 29-Jul-2010 08:44
Simply amazing, You, Sir just made my day.
Any chance of you doing an "Outrun - Splash wave" video?

It would make my life happy!
Anonymous
Thu 29-Jul-2010 11:20
we love you!
from italy
Anonymous
Thu 29-Jul-2010 12:11
Király állatság!!!
Anonymous
Thu 29-Jul-2010 21:49
Aztaku...!! Hát ez nem semmi! Leborulás!
Anonymous
Fri 30-Jul-2010 03:47
Sir, this is the most awesome thing of the day. You would rock at Comic Con!

Dude, Kyle, Sir, is that you?
Anonymous
Fri 30-Jul-2010 07:12
молодец!!!!!!Талантливые люди всегда себя проявляют!!!!!!
Anonymous
Fri 30-Jul-2010 09:56
Thing of the day! You are good engineer!
Anonymous
Fri 30-Jul-2010 19:24
Sir, this is really really fantastic, keep up the good work! You'll be making wonders if you continue like this. By the way: visit http://iddqd.blog.hu/ , where your video has been linked... ;) This is one of Hungary's most famous gamer blog. Cheers from Hungary!
Anonymous
Fri 30-Jul-2010 19:27
Good job! Congratulations!
Anonymous
Sat 31-Jul-2010 04:51
Наврятли ты знаешь русский.Но все же пишу так).Круто) за тетрис спасибо)
Tommy-Cat
Томас Игоревичь
Sat 31-Jul-2010 07:52
I have a few questions:
-why didnt you used an already build atmega solution like CraftDuino/Arduino and is there any chance that someday you will make a pair of this retromachine for those who are in need?
Anonymous
Sat 31-Jul-2010 18:42
Simply Awesome
Miss the 8-bit times
Anonymous
Sat 31-Jul-2010 22:43
THIS MARKS A NEW ERA! IT'S JUST MARVELOUS!
Anonymous
Sat 31-Jul-2010 23:25
Detta är det mest imponerande jag sett på mycket länge. Sjukt bra ljud också :)
Fantastiskt gjort!
Anonymous
Sun 1-Aug-2010 23:31
Реально круто!!!! Мужик, ты молодец
Anonymous
Sun 1-Aug-2010 23:53
I want your babies. All of them. This is the most AMAZING mod of ANYTHING EVER.
Anonymous
Mon 2-Aug-2010 01:33
Congratulations, it's awesome!
Anonymous
Mon 2-Aug-2010 03:35
måste bara säga att du är ett geni... jag verkligen ÄLSKAR 8-bitars ljud och hade nog gett i princip vad som helst för att få tag den eller att lära mig hur man gör en...borde nästan starta en massproduktion av detta och bli miljonär.. keep it going!=)
Anonymous
Mon 2-Aug-2010 07:04
I think this is great, you're giving it some life! I'm actually a Hammond organist. Mine's just like that one, except it uses a tube system instead of a solid state one. The Hammonds are by far the most valuable and desirable as antique instruments. Any tonewheel organ that isn't a Hammond isn't particularly valuable in its original state, but it makes for a great steampunk keyboard! Rock on, dude! :D
lft
Linus Åkesson
Mon 2-Aug-2010 15:42

Tommy-Cat wrote:

I have a few questions:
-why didnt you used an already build atmega solution like CraftDuino/Arduino

I don't see the point of them. The bare ATmega88 (DIL package) is powerful and user friendly as it is.

Tommy-Cat wrote:

and is there any chance that someday you will make a pair of this retromachine for those who are in need?

Currently, I don't have any plans to make another one. But I might change my mind.
Anonymous
Mon 2-Aug-2010 22:32
if u do so.. im willing to buy one!
Tommy-Cat
Томас Игоревичь
Fri 6-Aug-2010 10:01

lft wrote:

Currently, I don't have any plans to make another one. But I might change my mind.
Totally agreed, chipophone is exclusive to make even few of them, but how about some midi controlled box with few knobs and buttons made exclusively by lft? That would be awesome :)
Anonymous
Sun 8-Aug-2010 07:52
Congrats Linus, you and your machine are just awesome... i'm without words.
Tommy-Cat
Томас Игоревичь
Sun 8-Aug-2010 14:34
wanted to contak via email but antispam filter rejected :(
Anonymous
Sun 8-Aug-2010 20:56
Amazing work! Any plans on publishing schematics/software?
Anonymous
Tue 10-Aug-2010 18:19
You are so fucking awesome :D
Anonymous
Wed 11-Aug-2010 03:58
Helt galet underbart! Vacker idé och klockrent genomförd.
Mycket bra jobbat! Vill ha en Chipophone i min studio. Nu!
/RobinTengvall.se
Anonymous
Wed 11-Aug-2010 13:03
Truly an amazing and incredible project. A fantastic array of sound. I'm looking forward to hearing the sound with the spring reverb in circuit, although a more reliable and stable reverb can be made with the AVR as well. But the spring reverb is more authentic, and more challenging to interface.
Anonymous
Wed 11-Aug-2010 17:34
This is so awesome! Keep it up! :D
Anonymous
Mon 16-Aug-2010 05:56
Awesome project. Good luck with the reverb tank and the internal speaker - you know it would sound that much sweeter with both of those! Maybe catch you at a party one day (whenever I'm next in Europe) cTrix^DA
Anonymous
Mon 16-Aug-2010 15:11
Why you haven't used the already present power supply and power amplifier to have internal amplifcation? I think most the components are already there. If the problem is of dead electrolytics, you can even try to reform the original ones.
Anonymous
Tue 17-Aug-2010 03:41
Excellent work! Now make it AY-compatible :-)
lft
Linus Åkesson
Tue 24-Aug-2010 18:00
Why you haven't used the already present power supply and power amplifier to have internal amplifcation? I think most the components are already there. If the problem is of dead electrolytics, you can even try to reform the original ones.

It's a valid point, but I'd have to reverse engineer the entire power supply, because I don't want to meddle with a 230 Volt circuit unless I understand it. Thus, using an off-the-shelf power supply is quicker and safer, apart from being more efficient.
Anonymous
Fri 3-Sep-2010 20:50
Well done man, seriously. Thank you for doing this. I would love to buy one if you ever start selling them. You stand to make a good amount of money I assume.
I would totally buy one.
Anonymous
Tue 7-Sep-2010 21:34
fantastic man, you rock

id pay big money fro one of those ya know! =)
Sm00thie
Emil Hjort
Thu 9-Sep-2010 03:05
Jag fick syn på dig idag via Wimp. Måste säga att det var kärlek vid första tonen! Älskar hela 8-bit soundet =) Fortsätt skapa örongodis! Introt till "Robo Warrior" om man får komma med ett förslag ;)
Anonymous
Tue 21-Sep-2010 15:24
Really looking great! I'm very impressed!

Keep up the good work!

Cheers,

Reyn Ouwehand
paulj0557
Mon 4-Oct-2010 21:53
the thing you wrote about the pedal struck me as a very creative solution back in the days. friggin awesome to use photo sensitivity in this context. good to see the love you have for life, music, technology and with everything that you do. cheers!

Did you know that Morley guitar pedals ( the big chrome ones) all used the light-bulb/curtain method for their foot pedals? The pedals were all 110V AC and the AC light bulb for the red power indicator served as the light source for this make shift 'opto- resistor'. If the power light was out then you knew the pedal wouldn't work. On ebay I once bought a Morley Wah/volume pedal for $15 because the owner said " It was working and then one day the light went out. Selling as-is."
Unlike potentiometers that wear out over time and become scratchy the photo cells do not. Craig Anderton designed a mod intended for a Crybaby wah that instead of 'defacing' it and making it optical, he built a tiny circuit that isolated the pedals original pot from the circuit and used it to control a variable resistor in his circuit. So regardless of how scratchy its resistive element became the pedal would still sound normal. Don't know where I saw it, but it could be handy in rare instances. Personally I'd just change out the pot with a good Allen/Bradley one.
lft
Linus Åkesson
Fri 8-Oct-2010 07:23
Really looking great! I'm very impressed!

Keep up the good work!

Cheers,

Reyn Ouwehand

Thank you Reyn!
Anonymous
Thu 14-Oct-2010 17:24
Most impressive good sir. Personally I'm working on chip concertina, this has been helpful and iformative indeed.

Greetings from Iceland
Anonymous
Fri 15-Oct-2010 20:54
пиздец, да это охуенно, чувак!
Anonymous
Sat 16-Oct-2010 15:59
How much to fly you, and your organ to Canada to preform for my birthday?? :D


Great work, thanks for sharing your amazing talent with all of us!
Anonymous
Mon 25-Oct-2010 14:13
How much would it cost to have you build me one?

I'll build you one for $15,000. :-P
Anonymous
Mon 15-Nov-2010 00:53
I Love this type of music, and are vere impressed of you making of the Chipophone

i hope you play the Chipophone on a show i Stockholm somtime i will see in live

Great work
Anonymous
Mon 29-Nov-2010 19:28
Wow - what an amazing project! Well done, and I've downloaded Spellbound because its a favourite - thanks!!
Anonymous
Sat 11-Dec-2010 20:33
This is fantastic! I saw the video you placed on youtube, where you described the chipophone, and while there was some, I think that you definitely need to do the full Comic Bakery!
Anonymous
Sat 8-Jan-2011 21:30
Excellent mod. The light bulb and photoresistor arrangement in your expression pedal was extremely common on expensive analog audio equipment. At the time it was the only way to provide an inexpensive noise-free variable resistor. I have a cache of salvaged dials and sliders and other devices like that which work that way. These were used on studio mixers, for example. The same arrangement of bulb+photoresistor is used to provide electrical decoupling of audio gear. The inputs on high end mixers would often be a 1V light bulb attached via a metal tube to a photoresistor. Very clever and very effective.
Anonymous
Mon 24-Jan-2011 07:29
I found an organ donor as well.

Linus, is it possible you could release the source? I believe I can piece together the hardware fairly easily, but for the coding I'm just at a loss.
Anonymous
Sat 12-Mar-2011 23:41
Amazing stuff.

I am truly in awe! I've played the main Chipophone video on youtube to all of my friends now and everybody loves it.

Keep up the good work.
Anonymous
Sun 3-Apr-2011 21:39
Fan va coolt! :D
Anonymous
Thu 26-May-2011 18:31
Linus,
I believe the reason for having 12 oscillators was that there was a school of
thought in the 70's (I'm old enough to remember :] ) that it sounded better if the adjacent notes where "free phase" - i.e. not locked in sync with each other. Dividing down the semi-tones from a single oscillator was perceived to produce a "flatter", less complex sound.
Of course, the hard-core elite insisted that meant that you should have a separate oscillator for each key on the keyboard. However, for most purposes one for each note and dividers for the octaves was sufficient and saved a lot of time tuning.

Ian K Rolfe
Anonymous
Sun 17-Jul-2011 13:31
In case you're curious, the volume pedal design with the light and photocell is still very common. No moving parts to wear out, you see. But it is nonlinear and requires analog support circuitry.

In the digital domain, you'd use some kind of quadrature encoder and process the pulses directly. But unless you can actuate it directly over the distance of pedal travel, you're going to have some kind of mechanical system to convert a dozen degrees of rotation or a couple of cm of travel into 256 MIDI values. Look for components which will tolerate a million cycles of use.

An easier solution would be to use polarising filters on a drum assembly. Cheap and cheerful and long lasting.

Great work by the way. You need to speak to access-music.de. They'll sign you up.
Anonymous
Thu 8-Sep-2011 11:19
It's simply amazing. It's all of my childhood's sounds, I'm getting emotional ahah.
Thanks a lot.
Anonymous
Mon 12-Sep-2011 02:01
Fantastic work Linus! David, a colleague of mine sent a link to our internal hardware development mailing list and watching the video and reading about your work has quite made my morning :)
DellAnderson
DellAnderson
Wed 14-Sep-2011 02:56
In case you're curious, the volume pedal design with the light and photocell is still very common. No moving parts to wear out, you see. But it is nonlinear and requires analog support circuitry....

True - I believe Allen Corporation first patented it in the US decades ago, and Rodgers organ still has an upgrade kit for their older organs that didn't have it to begin with (early 70's?). The problem that the photoresistor method solved was that simple potentiometers had a nasty tendency to get scratchy and drop outs with the heavy use a volume expression pedal gets. It's actually quite cool that this small organ had a photoresistor pedal expression in it.
Anonymous
Fri 21-Oct-2011 03:54
I would seriously pay around 700$ US for a contraption like this. Perhaps you should look into a mass producing situation for us geeks out there in Awe of your amazing device.
Anonymous
Sun 30-Oct-2011 03:08
I would seriously pay around 700$ US for a contraption like this. Perhaps you should look into a mass producing situation for us geeks out there in Awe of your amazing device.
sadly he could not as he did not design his own organ so some aspects would be copyrighted.
Anonymous
Sat 14-Jan-2012 01:42
Well, I won't post "anonymously", but I won't register an account here, cause I have a zillion accounts everywhere. The Chipophone is a brilliant piece of hardware, but what you did with it (playing several of my tune on it in a way that nobody would ever be able to do has meant a lot to me!). I am really glad that I finally saw a picture of you where you smiled; cause during the music performances you really looked like a too serious bloke! :) Thank you for your efforts towards "our" scene and I hope you will prosper in every single way. (Jeroen Tel / Maniacs of Noise)
Anonymous
Sat 14-Jan-2012 01:45
Tune = of course TUNES (argh, damn typos @ 1:45 am at night ... LOL (Jeroen Tel / Maniacs of Noise)
Anonymous
Sat 4-Feb-2012 14:34
You rock! I'm now trying to find one of those organs, but no luck in Canada.
Joey Todd, Canada
Anonymous
Sat 14-Apr-2012 03:09
you are awesome. nice work.
Anonymous
Fri 27-Apr-2012 17:41
Thanks for sharing!
Anonymous
Sun 20-May-2012 20:30
You could make real good money with your live acts!

Maybe you should come to Rotterdam in The Netherlands! That would be so awesome.

Walter
wloch@live.nl
Anonymous
Tue 3-Jul-2012 16:32
This is absolutely best/most amazing nostalgic project I've seen over the years.
Respect, sir!
Weazel
Tue 7-Aug-2012 03:44
this is so amazing u should post all the info for others to build if u havnt
i so want to build mi own this would be the best thing to motavate me to learn piano
Anonymous
Tue 7-Aug-2012 09:40
Skicka ett prisförslag till mig är du snäll, om hur mycket det skulle kosta att bygga om en gammal yamaha elorgel johansson.raymond@gmail.com
Anonymous
Wed 28-Nov-2012 20:36
You sir, have won. Congrats!
Anonymous
Wed 28-Nov-2012 22:05
Congratulations, you are now famous on reddit! Very neat project. Thanks for sharing.
Anonymous
Thu 29-Nov-2012 05:33
very, very, nice!
Anonymous
Mon 3-Dec-2012 01:16
SHUT UP AND MY MONEY! :D
owning a chipophone would be the greatest thing i ever dreamed for! you should REALLY consider to build and sell units...
Anonymous
Mon 3-Dec-2012 08:13
This may well be the best thing I have ever seen, in my life.

Where do I sign to sell my soul for one?
Anonymous
Thu 3-Jan-2013 08:56
This may be the most beautiful instrument ever. You have to show exactly how to do it, meanwhile Ill hook up the soldering pen.
Anonymous
Thu 3-Jan-2013 15:06
a proper fix to an organ... sweeet. C64 would sound way better in chuch ha ha
Anonymous
Sun 24-Feb-2013 01:25
Is there any way I could get a schematic for this?
Anonymous
Wed 27-Feb-2013 03:07
omg dude, i want one so bad! D: there at least needs to be an app or something :P great job, this is amazing! these need to be mass produced, and you get credit :D you are freaking awesome dude!! :DDDD
Anonymous
Wed 29-May-2013 23:57
i just stumbled upon this through youtube. i am amazed you did this all on your own!! you guys in sweden are bad ass :D have the best day!!
JohanB
Johan B
Wed 12-Jun-2013 16:49
Genialt!
Hittade just den här sidan via YT, helt otroligt häftig konstruktion.
Jag hoppas att du någon dag gör ritningar osv. tillgängliga.

//Johan
Anonymous
Tue 7-Jan-2014 12:12
Absolutely amazing. Kudos on an incredible creation, my friend! -Tyler Larson (USA)
Anonymous
Mon 9-Jun-2014 07:46
Just awesome!
Anonymous
Thu 8-Jan-2015 23:25
Thats great! How much are the costs for marterial?

Jerry , germany
Anonymous
Thu 28-May-2015 14:18
This is very awesome! I hope you should start a kickstarter campaign for this and get rich.... Just sayin' LOL xD Anyway, it is very impressive! :)
Anonymous
Mon 5-Dec-2016 03:20
How much would it cost to have you build me one?

I'll build you one for $15,000. :-P

With shipping to the US? If so, I'm in.
Anonymous
Mon 5-Dec-2016 03:25
Are you willing to release a binary for the 88?
Anonymous
Fri 18-Aug-2017 22:45
¿What tools and objects do I need besides 8-bit microprocessors and the organ?
Anonymous
Mon 19-Feb-2018 13:25
Good Work...
Anonymous
Thu 27-Sep-2018 21:48
I want to get one of these !
Anonymous
Sat 1-Jan-2022 09:44
I have a 89,000 dollar offer for the chipophone, and would like to buy it. May I?
lft
Linus Åkesson
Sat 1-Jan-2022 15:11
I have a 89,000 dollar offer for the chipophone, and would like to buy it. May I?

That is a respectable sum, but the chipophone is quite dear to me so I think I'll hang onto it for the time being.