Casio CA100 Line Out Modification and Demo (Realistic Concertmate 670)

[@NielsCG]

I just found a Casio CA100 for $5.. but it's in terrible condition... so i'm doing my first keyboard restoration "8 bit key's" style!! wish me luck!

[@aubudjdhueh4501]

Luis Niels how did it go

[@RickyRat256]

Did you do it?

[@NielsCG]

@@RickyRat256 Yes I did it... complete restoration, look brand new!!

[@jamieslifee]

@@NielsCG rcde M

[@adenarrington7607]

@@NielsCG could you post a video to your channel of the restored ca100

[@Fixmix78]

As an audio engineer I have to say you should listen to the end of the recording chain. If you listen to the beginning, i.e. the source, you might not hear problems further down the chain, e.g. buzzing or distortion. Just my 2c.

[@AiOinc1]

Sadly this can make it really difficult if you're playing the instrument and you use a digital recording device, which can often add a bunch of delay into the sound.

[@AndersEngerJensen]

You can hear the Casio sound underneath the hood no matter what brand they slap on top. Why they put Brass as the first one is hard to tell, because on the Hohner PSK range (same as the Casio MT series), they grouped the sounds more traditionally with Piano, E-Piano, Harpsi, Vibraphone etc first. Maybe the Radioshack guys had a say in how they wanted it to be? How is the layout on the real Casio CA-100 in comparison? :)

[@8BitKeys]

its exactly the same on the real CA-100. However, I have a Yamaha keyboard from the same time period and same target price/demographic and it also defaults to a brass instrument (trumpet, I believe) and I scratched my head on that one too. I think it boils down to engineers making a toy and not having any real musicians being part of the design team.

[@nedratio]

8-Bit Keys Hi Hi I love your channel

[@LovroSabljak]

Layout on real Casio CA-100 is the same... I have it myself :)

[@AndersEngerJensen]

Lovro Sabljak Hmm, then it's another reason for it. Guess we have to find one of the engineers who worked on it back then... 😜

[@LovroSabljak]

:D

[@NeapolitanHusky]

I actually have this exact keyboard myself! Radio Shack rebranding and everything. But one correction about the polyphony at 8:31 . You can actually have up to 8-voices on every instrument. The instrument select button also has a label that says "poly/texture". If you press the button, it alternates between limiting the keyboard to 4-voices and giving you a more "textured" sound (which just seems to add a bit more reverb or some sort of modulation) or giving you the full 8-voices without any "texture". Thus the actual complexity of the instrument doesn't really actually matter. It's just dependent on if the instrument is set to "poly" or "texture" mode.

[@Dioxaz]

+Neapolitan_ Husky I was about to write an answer myself when I read yours. Also, he didn't try the auto-accompaniment feature which limits you even further: 2 notes in texture "mode" and only one note in "poly" mode! I also have the same keyboard from when I was a kid. The interesting part is that when you remove the Realistic label on back, you find the original "CASIO CA-100" brading directly on the plastic. However, I suspect the sounds be actually PCM (I didn't belive it back in the day) but very short looped samples, like wavetable. Nobody bothered ripping the content of EPROM chips (if it's technically possible) from the Casio CA line so I can't really tell.

[@dodgeramsport01]

@@Dioxaz This also labled as a Hohner PSK 20

[@blinx88pl]

I had this exact keyboard when I was a kid. It was actually branded Casio but had the same demo tune as yours. Oh, the nostalgia *.*

[@thomasrosebrough9062]

I am always impressed by the large chunks of your videos that you record in one cut, like you did at the ending of this one.

[@Creepus_Explodus]

So the Casio keyboard rick rolls you, when you play the demo tune?

[@maders0405]

it might be a different song.

[@6344Dragonkingon]

Could be Together Forever or whatever

[@Earthbadger]

Ah crap looks like I was to late to make that joke then

[@comptonrapper601]

It's actually together forever and not rickroll :(

[@mystica-subs]

Casio SA-1 plays Wake Me Up Before You Go-Go

[@TheIslandDivision]

Scored a CA100 from Value Village today. Only $4.99 Canadian and works!

[@shreyaskul]

You can short the internal switch of headphone socket on circuit to keep internal speaker ON even when headphone jack is plugged in.

[@nikgolinar4378]

Shreyas kulkarni or hook it up to a switch, so it can also be only on headphones

[@Reneg3r]

The demo song at 6:00 is "Touch in the Night" from Silent Circle

[@mineteam0]

I don't think that's it.

[@yournamehere23435]

Fun fact, a tv gameshow from my country in the mid 90s used the sound at 12:00

[@yournamehere23435]

Chile. The show itself was called "time is golden" when translated into English. It's the same sound but i woudn't be able to tell you if it was from this exact keyboard or not. PS: I had a Casio SA when I was a kid, it was my first keyboard

[@anwiseru9064]

i swear that sound is used in some Death Grips song

[@nneeerrrd]

You got a *Silver Button!* Congratulations, man! Been with you since circa 20k subs. Keep up great job!

[@fungungus]

The realistic concertmate line is surprisingly good. The concertmate mg-1 is a real powerhouse

[@ChasD]

That's because the MG-1 was made by Moog, and is basically a Moog Rogue in Realistic clothing!

[@onesixfive]

When my grandfather died and his house got cleaned out we came across this exact Realistic synth. Apparently He fooled around with it. I took it home, it had a black plastic molded stand it sat on as well. I had it for years. I used to take line out of the headphone jack into my 4 track and monitor through that. I composed and recorded many primitive hip hop beats with this thing and bass played through a practice amp, that i would mic through a garbage can I punched a hole in the bottom of and fixed to the end of the amp. Eventually I was going to junk it but my girlfriend at the time said she wanted it. When you zoomed into the list of sounds I got a chill as I hadn’t seen it in so long. Great mod and great vid.

[@superluig164]

I had a little keyboard with the exact same synthesizer as this as a kid. It also came with a song bank, with Ode To Joy. I used to call it the "piano song" and when I learned to play it I was so happy lmao

[@bbbc4294]

Radio Shack actually put final assembly date codes on most of their devices. On the bottom, it has "6A0" on it, and that is the date, where the first number is the month, 1-12, the "A" is a spacer, and the last number is the final digit of the year. So, your keyboard was assembled in June of 1990.

[@cjhoyle]

Another trick you can use to get line output is to unsolder the leg of the headphone jack which causes it to mute the speaker when there is something plugged in. This essentially turns your headphone jack into a line output. I have a much newer Casio keyboard where I did this and also added a little switch so I can change whether it's a headphone jack or a line output jack.

[@etiennelj]

He just likes to do (unnecessary) mods and make up reasons for doing them... I think it's more about the process than it is about the result, in spite of what he might say.

[@gonXay]

I believe most of these connectors that "auto mute" mechanically disconnects the speakers when something is inserted. Drilling a new hole would be sensible in that case, as that would put it on par with most modern keyboards that have both a headphones and a line out connector.

[@ulisesvzv9518]

what is this leg on the jack? i have one but i dont know :S

[@eemeli7093]

@@etiennelj if you dont like the channel, dont click on the videos or comment!

[@zdave6083]

@@eemeli7093 why not ? Diverse opinions make for a richer discussion. Criticism prods innovation.

[@Anonymous-xn2xh]

The casio will never give you up, never gonna let you down, never gonna run around and desert you. Great ad

[@TopThrillTravis]

Wow, I had this exact keyboard when I was a kid, hearing that demo track just brought back a flood of memories. It wasn’t much but it certainly gave me many hours of enjoyment. Thanks for showing us this! 👍🖖

[@EpicLPer]

Pfahaha I love how at 6:17 he just reversed the soldering clip because he probably forgot to record one :D

[@8BitKeys]

That's exactly what I did.. and yes, I forgot to record it.

[@LohTec]

Didn't even notice :) When content trumps errors.

[@CIubDuck]

EpicLPer I noticed how unusually fast the soldering went at that part, but didn't notice it was in reverse lol

[@ThatElectronicsFool]

gir489, The only way to recapture the genie!

[@deelan_]

YOU ARE F*CKING TOPCOMMENT AGAIN! STOP YOU BOTTING

[@mitchmatthiesen5855]

@ 8-bit Keys I have the Casio CA-301, CA-401, CTK-100, CTK-120, CTK-130, MA-101, MA-120, MA-130, and MA-201. All of those keyboards are based on the same sound chip as the CA-100. I also have the Casio CT-400, CT-840, and MA-220. Those three keyboards have similar sound hardware, but a few of the sounds are different from the other afore mentioned models. For example, the piano sounds more realistic on the MA-220 than on the MA-130. I also have in my vintage portable electronic keyboard collection the Casio CTK-150 and one of its bigger brothers the CTK-300. Both keyboards have a lot of the same sounds as the other models mentioned above, but here some of those sounds improved resembling what they’re supposed to be, such as the trumpet and the harpsichord for example. However, some other sounds such as the accordion and the bagpipes didn’t improve at all.

[@derirrevomzombiehof4893]

11:16 The Casio Ca 100 / realistic concertmate 670 has 5 bass species, namely 29 = slap bass, 30 = elec bass, 31 = WOOD bass, 32 = snare bass and 69 = synth bass, in which the lower seven keys as drums act. Nowhere in the operator instructions is this function documented!

[@perseverance8]

I just picked one of these up at a Yard Sale for $6 with a “QuikLok” stand. I’ve been keeping my eyes open for one of these keyboards in satisfactory condition for some time, I lucked out & found one that came in it’s original box with everything original present along with a nice stand. The people at this Yard Sale had no idea what they were offering, I was able to walk away with MANY other items I’ve been looking out for in addition to a Japanese Imperial Navy leather cap in oddly good condition, the seller’s claimed original owner is a grandfather who served in a not specified branch of US service who didn’t serve in Japan, however owned many items which apparently originated from Japan of WWII era. Including early Honda items, including a Honda E40 & Honda “Cuby” engines & kits!

[@MaverickGrabber71]

You finally got a step bit! 😃 The old drill and switch to next larger bit approach was killing me. 😂

[@VincentJanssen123]

Congrats on your 2nd 100k+ channel!

[@AttilaSVK]

The sounds of this keyboard bring back so many memories to me... I had the Casio MA130, which has almost the same sounds, but has a smaller keyboard. I even did some multitrack recordings with my dad's stereo reel to reel by recording off one channel to the other and adding a new instrument every time. (I also used it for some echo as well)

[@askhowiknow5527]

I love glass harmonica, it's like an intro to an 70s Sci-Fi movie

[@PanosDCC]

Can't wait for the PSR-6 review. Had this keyboard as a child, and lots of good memories spring to mind because of this thing. Love it, always did, best keyboard ever as far I am concerned...

[@Katerpillar]

Congratulations on 100k subscribers here on 8-Bit Keys

[@fernandiwxbc13]

I can not believe it! I used to have this keyboard a long ago, until my brother tried to "Fix a key" and the keyboard ends all disable and loose. Great work on both of your channels, keep it up like that! Grettings from Ensenada Mexico!

[@fanatic26]

I recently pulled my CA-100 out of storage and it was not working properly. I would flip the power switch and it would light up for a moment and then die. This video helped me take apart the whole thing and after checking over all the components I had a stroke of genius and looked at the power switch itself. There was so much gunk on the board from being in storage that the power switch wasnt making contact. A bit of contact cleaner and 136 screws later I once again have a working keyboard :D

[@granworks]

Congratulations on hitting 100k subscribers on your second channel! Well earned.

[@MyNewSoundtrack]

Awww my old Casio CTK-100 had that demo melody in it, brought back some nice memories

[@MyNewSoundtrack]

Now that I'm hearing the demo sounds, they're EXACTLY the same samples from the CTK100 :O

[@poplharris]

MyNewSoundtrack what year is that ctk 100

[@MyNewSoundtrack]

poplharris 77 not sure, I got it as a present when I was 5 back in 1999.

[@florentjendrysiak3396]

I think the inverted signal sent to the speaker is called a balanced output signal. It's made to eliminate electrical noise during the transmission of the signal. I guess that's why you get a better signal from the speaker.

[@technology4617]

it's called a bridge-tied load configuration, and he correctly identified the reason this was done at 5:27. it has nothing to do with common-mode noise rejection in this context. the audio rip using the inverted signal as a ground reference should be 6dB higher in level than the chassis-ground version.

[@florentjendrysiak3396]

@@technology4617 Okay thanks for the correction, It's configured that way to amplify the signal and not to correct noise if I understand. It would only cancel the signal if it was not inverted.

[@NicDroid]

Oh, this keyboard! This is my Dad's first keyboard and also mine since I learned how to play piano when I was 9. Brings back memories!

[@awyeh1234]

Oh the amp chip is being used in bridge mode to give more power to the speaker, it’s a way to use a stereo chip in mono, but with a higher output wattage using both parts of the amp

[@superlew12080]

I had this keyboard (the Casio) as a kid. I completely forgot about the demo. Thank you.

[@LordBete]

Jesus the demo song on that keyboard brought back some memories of my old keyboard! Edit: It turns out the keyboard I had used the exact same internals just in a different shell

[@Jones12ax7]

Hi, I just got a Casiotone MT200 with my mother to restore. That was the keyboard we had in in 1986 when I was a kid. Inspired by this channel I'll restore it, including a retrobright. It was a very good keyboard for that age. Very simple, but has decent sounds, stereo line outputs and at last 8 keys polyphony. Also, it has an unknown computer port that I plan to discover what is that for. As kid was curious about that I never found it out.

[@HisXLNC]

This keyboard was my second keyboard ever. This vid brings back so many memories. I remember using that demo song for intro to my fake radio show as a kid.

[@sebastiancardenasholik]

Hey, ive been seen your vids for some time now, i realy was waiting for this keyboard, i grew up playing with it and loving/hating it. only used it as a toy as a kid, then saw it as an old thing. But over all, i think these kind of keyboards touch something deep in your viewers lifes, some memories or some dreams left untouched from growing up. Thanks David, From Argentina a great thank you.

[@Patrik2166]

David, the main reason why you record from the input of the amplifier is that the Amp's noise adds when you amplidfy your signal. If you use the method you said before (record directly from the inputs of the amplifier) then you'll get a less noisy signal. If your amp is a low noise amp you can just use the outputs directly but if it is a noisy one (not realy used in audio technics tho) you should get the signal from the inputs instead of the outputs. In most cases try to use the amplifiers inputs for the line output for clear audio. Love the show :)

[@macupgrader]

I actually had the casio equivalent of this keyboard as a kid and it definitely had the demo song you played in the video.

[@tohopes]

I wonder if that chip has a sustain input... if so, perhaps you could add a pedal jack.

[@Koraniz]

love to see you get one of those professional keyboards that had a built in floppy and can program in your own beats

[@dazzlesoftware9319]

I had so many classic keyboards over the years some I wish I still had, now I 35 I been slowly rebuilding my old retro collection from DX7, Yahama DJX, Even now sounds amazing still, Yamaha sy35, Yamaha PSR 520

[@coondogtheman]

I had a keyboard like this. This one looks exactly like mine but was made by Casio. I liked all the sound effects. 10:18 The sound that played when you hit the right most keys I always thought sounded like an alarm clock.

[@fisqual]

OMG I used to have the Casio version of this! It's so cheesy sounding, I love it and I especially loved the TOGETHER FOREVER demo on it.

[@fisqual]

And #88 was my favorite sound.

[@Locomamonk]

I have had it for 31 years and counting, without ever needing to repair it. I've listened to that demo a thousand times at least

[@CattoRayTube]

Casio, c.1990: "The piano sound is awful. Bury it behind the brass."

[@Vlad0_SvK]

ConGratulation for 100 000 subs on this channel!

[@jairounvet]

My first keyboard right there. I got the Casio one. Those sounds got me back in time. Very nostalgic.

[@TheMr77469]

Yay for use of the piano meter once again, seemed to be missing from some past ones.

[@matthewrichards88]

This was my first keyboard. I still have it!. My father got it from Tandy's (that was RadioShack equivalent here in the UK). That demo tune is full of nostalgia for me. I used to play it all the time.

[@joshblaho1919]

Just picked myself up a Casio CA-110 at Goodwill. I have a Behringer 25w amp that can work as a preamp with L and R output. I would recommend getting a small amp like it. It would save you the hassle of finding the amp on the keyboard, soldering, and drilling. You would have no input delays. Also, you get the added benefit of stereo v mono; as well as, you would be able to make adjustments to gain, bass, mid, and treble. Mine was just $100. I know you said you don't have a studio, but I think for a buck it would be a good investment since I have seen you do this more than once. This merely a suggestion. I'm not telling what to do. Also also, they had a behringer guitar amp at the same goodwill that was a 30w for $50 that had the same function. I'm in CO though not TX :,(

[@antuananartistamultidiscip7925]

They are the same sounds as the Casio MA-100, although the MA-100 doesn't have any type of audio output. This video will help me if I dare to put it on mine. Thank you!

[@jcamou012]

You can slightly alter the tone bank sounds by pressing the "poly/texture" button again, its a feature that no one talks about. bumping the keyboard from 100 sounds to 200.

[@EYTPS]

OMFG GUYS 8BIT KEYS HAS 100,000 SUBS LETS CELEBRATE!

[@tigrom01]

I had this exact keyboard and was always disappointed with the sound (lack of) quality! I'm glad I wasn't wrong!

[@ProDigit80]

7:28 I think because the voltage provided to the speaker is around 2V. If the speaker is 8 Ohms, it will run at 2.25W. If the speaker is 4 Ohms, it will run at 2.5W. They basically cut out a poweramplifier, and just installed a cheap speaker on their line signal; since every system actually has a soundchip, a line amplifier (for line out), and a power amplifier or two. It's probably an FM chip. 9:38 I think they just dual layered instruments, causing it to sound like it was an octave higher. Yamaha Clavinova has the same problem with layering samples. 13:43 Even with professional instruments, I end up only liking about 10 good sounds out of 500 bad ones.

[@theshadowman1398]

Congrats on passing 100K on this channel

[@SchokobomberLP]

the audio in this keyboard gets boosted by a two channel amp , so if you have only a mono spaeker keyboard but a stereo ampfilifier it gets brigded to double the ampfilfication. It works when both channels on stereo have the same data. This is a common method on car hifi ampfilifiers, cause they are often at least stereo but many people are using these for an extra subwoofer (1 channel) so you can bridge the amp and gain the power of the second transistor inside the amp.

[@SuperNicejohn]

Congrats on hitting 100k on this channel a few days ago :)

[@fnersch3367]

Doing this makes a lot of sense doing what you do. I plug my Concertmate into a Roland Cube thru the Phones jack. It sounds quite good considering this is all low end equipment.

[@KonnorLetterBee]

You got a step drill bit finally!

[@BjornThePiper]

I have the Casio version of this keyboard (or one very similar), and it has the interesting feature that when you press the "tone bank" button, it will alter the "depth" of whatever instrument you're using, giving you more or less polyphony. Also interesting is that on my keyboard Piano IS the top option. Also, it has the same demo tune - no Rick Astley.

[@proxythe1337]

Wow, man. That demo tune made me cry. I remember my grandfather had an old keyboard in his basement with the same demo tune, and when I was young and visited him, we would often go play with the keyboard. It sort of became our little tradition to listen to the demo tune before either of us would play anything. It's been a few years since he passed away. I miss you, grandpa. edit: Could you potentially capture a high quality sample of the demo loop?

[@AlexWindsor]

I am a professional pianist and I have the same problem with headphone output but no line-out, with the P- range of Yamaha keyboards (which are fantastic quality and value for money). I've had a P-60, P-70 and P-95, each has been well and truly been gigged to death. None of these keyboards have line outs - just headphone outputs. So I just crack open the case, and inside the headphone socket is a small piece of plastic (switch) that you can snap off and then by connecting the headphone output to an amp (mind you, voids the warranty) and you get the output come through the internal speakers as well - and this has never caused me any problems at all, after 12 years of gigging like this. Although, now I feel like the time has come in my career that I get a car and a Nord, and stop smashing my keyboards about on public transport !!

[@DrDingsGaster]

I have a PSR-6 I'm not as knowledgeable on the specifics of how they actually work but I absolutely love that thing. I got one from a second hand store as a young guy for Christmas and I haven't gotten rid of it. It needs cleaning but other than that it's still going strong.

[@Melcadrien]

It's these videos that got me interested in finding my own digital keyboard from a thrift store. I found two. A toy Casio SA-75 keyboard for 5 bucks and then a Casio CTK-531 for 10. Both in conditions I just had to clean the gunk off of.

[@NielsonLucas]

I have a Casio CA-100 and it still works fine.

[@n1fffan]

Wow, my brother actually had this very same keyboard when I was a kid. Wasn't too sure until I heard the demo track

[@darm2534]

I love this channel! I had been watching your other channel for a while and i love it and when I found this channel I can't stop watching :)

[@jpablo68]

I still have that model, mi parents bought it brand new here in Mexico, I always liked it.

[@captainturloc5938]

This is very technically advanced. You are to be commended.

[@CoolDudeClem]

I had a keyboard like that once, I think it was the same model as the one here I can't quite remember, but I do remember those same low quality sounds (I even sampled every one of them for some reason), I think it also had the same demo song.

[@misterhat5823]

You should not use a polarized capacitor when connecting to a BTL amplifier like this one. In addition, the keyboard can never share the same ground as the device you're connecting to or you're likely to have a dead amplifier chip.

[@peaceful1123]

(I agree with you.) I asked the same question before. Electrolytic capacitors can withstand 1 to 1.5V reverse voltage. Thus, line level AC should be fine in this case. Moreover, the keyboard itself's already isolated as a transformer's being used at the 9V power input. (But I would use a ground loop isolator whenever dealing with different voltage of ground.)

[@technology4617]

why is it bad to use polarized ac coupling capacitors with btl amps

[@AceRuiner1979]

I used to own a Casio mt68 I loved mine!! The one tone labeled as "Funny" was my favorite

[@danz409]

i used to have one of those. was fun to play with. but had too many limiting factors. wish i grew up with a better keyboard D:, still brings back soo many memories hearing the interments!

[@PedalingPrince]

I remember that Realistic branding thing. I am a big fan of Koss headphones and many headphones under the Realistic brand were actually Koss; you could tell because the Koss logo would be there, understated, somewhere on the headphones.

[@MaverickGrabber71]

PedalingPrince the Pro 35s were the best! Was glad to find the Koss version on Amazon after my last pair of Pro 35s got broken.

[@nrdesign1991]

8:22 Synth-sounds were 'in' at the time, so it made sense to make a keyboard appear as a flashy synthesizer rather than an old-fashioned piano

[@BulletProofCupid7]

In software like Reaper (or any recording software really) you can turn "monitoring" on a track to listen to what you're recording.

[@BulletProofCupid7]

in this case, which is recording toy keyboards, i don't think that would be a problem at all.

[@totaltotalmonkey]

Audacity also has a play though option.

[@johnfrancisdoe1563]

bpc7 But going through the computer creates a delay, which will mess up his playing.

[@ilpatongi]

Ryuhouji No it doesn’t, that’s what professionals use actually. Every DAW does this and the delay is so small you will never notice it, especially an amateur

[@benisboy2697]

My interface (ur22) has handy daw-input knob. Its really useful for recording and monitoring live. Basically no lag

[@PrankZabba]

can't wait for a multi keyboard multitrack recording of all the keyboards, playing the best sound on every single one.

[@compu85]

Growing up we had the Casio branded version of this keyboard (or one that was super similar). It had the same demo tune.

[@marioluigifun]

Hey, welcome back to 8-bit keys, it's been a little bit. Also, happy 100k subs! (Not sure when u hit that goal, but it's still cool.)

[@fnersch3367]

Just got one of these for $19. Works fine and sounds good thru a Cube mini amp. Thanks for showing the hack. May try it.

[@jonasgrill1155]

You could plug an Auxillary cable into the headphone jack of the keyboard, then plug the other end into the laptop's mic in port. Then, you can go into Audacity, press Ctrl+P to open preferences, go to the recording tab, then check the box next to software playthrough of input. Then, when you start recording, the keyboard would play through your laptop speakers. I know you probably knew this, but I'm just commenting this to be helpful.

[@facundopignanelli]

Missed your videos on this channel!

[@abcqwerty123400]

This new intro piece sounds amazing!

[@ItsDoctorAmatic]

I have a Casio CA-110 (it was my very first Keyboard back in the early 90s) and it has the exact same demo tune like that CA-100. I'm from Europe btw. - so no re-branded stuff.

[@DreitTheDarkDragon]

I don't know about you, but I'd put some heat-shrink on capacitor legs at 7:13 ;) Also, I'm just curious - if both outputs are floating, wouldn't it be better to put capacitors on both wires? Because now your CINCH ground isn't same as DC jack ground.

[@mystica-subs]

I miss those RadioShack days when all they had were their own brand name products. When I worked there most of their stuff was just ”custom manufactured in China for RadioShack” but that was the 2000s. 8-bit guy has something from the era of my youth - less than 3 ft tall walking around with my grandfather at RadioShack looking at all the cool things on the walls.

[@kelli217]

David, you do you. Make those mods if you want. You mentioned alternatives, like Y-cables, for those who don't want to make these kinds of changes to their keyboards. I would also recommend looking into small cheap console mixers as another possible alternative.

[@andyglbrt]

I have a Casio CTK-100 that looks a bit different but sounds exactly like that. Same demo and button press sound and everything. Built the same too with the circuit board on top and the OKI chip. Pretty much the exact thing just a more modern looking package and actually has the Casio badging.

[@fishnutter5219]

This was my keyboard growing up! I was forbidden from using any of the sound effect sounds without headphones on. :D

[@sparkyprojects]

The Casio LK60 i have starts with piano, followed by organ, guitar, bass, orchestra, then brass, plus a few others. I'm surprised your friend suggested the inverter was after the amplifier, the normal way to do 'bridge mode' is for the input signal to be inverted on one channel.

[@egs-zh3dt]

One thing to note about line out mods is to NOT use RCA connectors. RCA connectors are unbalanced, which means the sound loses quality in longer cables, whereas quarter-inch TRS connectors are balanced and don't lose quality. Always use TRS connectors for any sort of output.

[@jwhite5008]

Disclaimer: I'm not actually an electronics engineer, especially not a music-realted one. Your capacitor is WAAAAY TOO LARGE! You need no more than about 1uF..10uF cap. That's 100 to 1000 times less than the one you used. I won't be surprised if the sound you heard mostly came from leakage current - with the capacitor acting as a resistor. Also half of the time your cap is connected in reverse - VERY BAD for electrolytic caps. You probably did not notice yet because it is rated 50V and the audio levels are probably about 1V - that may be within its tolerance but still a bad idea. Electrolytic caps are mostly just for power supply filtering. Use a ceramic cap - they are unpolarized (mylar or polycarbonate should have less distortion, or so I'm told, but ceramic is fine for this project) More importantly, ONE CAP IS NOT ENOUGH when you are tapping into both leads of a balanced circuit - you need a second cap on second lead. This is because if power supply "-" is connected to a protected earthing on the 3-prong AC plugs on both sides, you are essentially shorting one lead to ground exactly where there is absolutely no protection against it. You probably didn't notice because the keyboard connects via an unearthed plug but it's asking for a disaster to happen. There's another problem with your setup - you connected a BALANCED circuit in your keyboard to an UNBALANCED cable+circuit in your computer. This has subtle side-effects like kind-of circumventing the shielding of your audio-cables. Normally you need something called "balun" which consists of a transformer and some optional resistors - you can buy one of these or just wrap 2 parallel strands of fine wire around a ferrite core. If you use a balun you should not need any capacitors, although you should connect a current-limiting resistor in series (I'd guess 10 ohm is fine, probably). However, since the keyboard won't actually produce any studio-quality Hi-Fi sound anyway, and you are not connecting it via a 10+ meter audio-cable, so you can skip the balun altogether and just use 2 caps.

[@russdill]

Yup, the most critical thing here is that he's potentially shorting the amp output to ground.

[@ilpatongi]

I don’t think the current nor voltage is high enough to cause any problems

[@NielsCG]

@@ilpatongi stick to cars dude!!

[@ilpatongi]

Luis Niels Stick to being useless

[@ttg_jamie6494]

No one cares

[@AlbertoCastillo2001]

Reminds me of my beloved Casio SA-21 keyboard which I still remember deeply, although I no longer have it. It was another PCM keyboard, and many, if not all, are the sounds of my keyboard. If you end up getting one I would love you to do a review on it. It's clearly a toy, but a very huge part of my childhood. By the way, that one began with a piano sound :)

[@TechnologySpotlight]

Congratz on 100K subscribers!

[@smheath]

I had this keyboard as a kid! And even back then, I thought it sounded terrible!