Yamaha PSS-100 Review & Output Mod 

'im no electronics expert by any means' *brings up a blueprint for the sound chips and wiring diagrams for the unit*

in the hands of an expert any instrument sounds awesome greetings from the ancient megalithic city of TIAHUANAKU BOLIVIA

Thank you for your respect for the basic (almost forgotten nowadays) principles of a REAL, IN-DEPTH review - so detailed, so thoughtful, so organised, so well narrated, so nicely edited, and so honest. Thank you for your respect for viewer's eyes, ears, brain and ...time. Your attitude and the content which it lives in represent what I would call THE HEART of social media. Subscribed with pleasure!

This keyboard is a must have for every chiptune lover

I had the PSS-80 and I sold it to the kid across the street in my old neighborhood. It was an amazing little box and I hope it served him well.

Kudos for the 110% creativity level in your videos! Sounds smashing!! 🤘🏼🤩

It's good to see your channel getting some activity! Excellent refurb & review as always!

Thank you for the wonderful albums on bandcamp, I hope this channel grows to the millions of subscribers it actually deserves :)

Been loving your videos ever since I got an shs-10 a few months ago, keep up the great work!

Because of your videos I finally gave my PSS-460 and PSS-580 teardowns and services and got them all working right. Thanks :)

Great video! This is one of my all-time favorite keyboards. Its sound reminds me of retro video games and it’s a blast to play.

I like the vibrato effect and the fantasy tone. Thanks for the great review!

The recorder is brilliant. I didn't know that a toy keyboard back then had such sequencer controls. Had to comment in an attempt to support your incredible video and channel. Greetings from a regular Casiotone MT-240 player.

Excellent review. Clear, deep, well played. I'm waiting for mine! I bought one a few days ago on ebay.

Very good! Just some ideas: To remove the "beep" sound you need to disconnect the wire that goes to the CPU, removing the capacitor 470pF would do the job. To reduce the volume of the output, the better would be to make a voltage divider with two resistors, not only one.

Hi Keen on Keys! Just discovered your channel and I definitely think you deserve many more subscribers... Keep it up!!

I think I could never thank you enough for this video! ♥ I still keep mine from 1994 when my dad bought it for me. It has been with me since Im 4 years old, and even though I'm not good at making any music, I have always enjoyed it and the samples have been a companion trough my life, I think I can recreate all of them vocally or whistling haha, now my sons enjoy it too. It still works pretty well but some time ago my brother broke the first white key. Ive been looking online for this model keys but no one sells them of course. I just found another PS100 (here in Argentina) that Im willing to buy to restore mine since the one on sale has te outside body broken but all the keys are fine. Im really happy to found your videos, they are amazing. Greetings from Buenos Aires!

jesus man, those videos of yours are so great I can't stop watching (instead of working!)

great review ! i found one of this and in few days im going to buy it to and to make output for music making ,thank you

Excelent video/demonstration!! Keep them coming 😁 and Thank you! 😉

I love these little yamaha pss keyboards I have a Pss 270 myself that I found in a rubbish dump. So much potential out of them

Excellent work.

Hey thanks for the tutorial and schematic, great videos!

sehr guter Kanal. Danke für deine Inhalte

As always, awesome 👌🏻

Thanks for the great review and the mod. I just got this keyboard for 25€ and will do the audio out mod too.

You are unmatched (along with weltenshule table hooters guy) when it comes to us consumer level home keyboard collectors and users. Thanks for breaking down the output mod in such simple terms. Would love to see your take on the Casio MT-520--- it's a super drums unit, and the drum machine has many variations for all style, as well as mutes for specific drums/groups. Very versatile and fun instrument. I'm fairly certain it is at least partially based on squarewave synthesis.

great, as always. there's a simple filter between the sound chip output and the amp to smooth harsh digital waveforms - it's easy to drive it out (or to make it optional) for the "good direct sound" to pass through the amp. it probably is not a very good idea to take signals directly from the sound chip by wiring it to the jack. the already mentioned voltage devider is one resistor in the signal way, then another to ground. if they are equal then the output is a half of input, if first is 2R and the second is R, then output is 1\4 (well something like that, and that's how volume regulators work). as the native "volume regulation" is effecting the structure of the sound, just a pot in place of such resistors is a good idea for additional real volume regulation. or better a pot for the speaker and after that also fixed resistors for the output jack.

wow thats pretty better than the pss-80 that I own. BUT, surprise surprise, the test mode works the same way so you have access to the drums. Thats super cool!

I tried the startup trick on my PSS-80 and it works as well! Seven of the eight Voice buttons turn into drums.

Great channel! Thank you!

Wow, this thing looks like a chiptune monster machine!

I keep my eyes peeled for the 100 as it is probably the best of the lot but a bit harder to find. For now, I have the PSS-80 and the PSS-140 that you mentioned.

Arnold? Is that you? Incredibly review, by the way!

Some nice sounds can be had with that voice-variator. Im going to buy one for my Niece as she was really into my PSS470 today :D

Nice vid! Brings back memories. I had this neat little keyboard many years ago when I was a kid. I eventually through it out with the rubbish. Ugh 🙄

Theme tune of the Rockford Files !... didn't think I would hear that today.

I have the pss 140 all functions work save for the power jack and it's temperamental on how I feed it battery. But once the battery's are in right it sounds really cool.

LOVE THIS! Are there any mods that can be done to a PSS-F30?? Thanks for the great uploads!

Can you start linking any hardware modifications you post? Have a suggestion on where to buy the jacks? Loved the video!

That 16 beat tune you did with the accompaniment sounds like a rhythm heaven practice song lol

To disable the beep, take out the 470p capacitor on pin 15 of the CPU. It is coupled to the same path that the soundchip puts its signals, so it will bleed through. You also circumvented the filtering that happens before the signal enters the amp, so of course it's going to sound different. To get a more comparable signal, take the amp's input on it's pin 1.

Yeah, I saw on the schematic you shown, that the beep wouldn't go away because it's basically wired to that same pin with no parts in between, like a diode to keep the signal from reaching that pin.

this synth is clearly underatted

For me this one allways seem to be good in many styles of music, since it has very simple sounds and is possible to edit like a real synth, but for kids I imagine you could use this in both metal, goth, new wave and synth pop with a little bit of pedals.

to get rid of the beep you can scratch the trace that the sound goes through or cut the pin of the cpu that it comes from.

I loved It!

Test-mode drum-machine hack!!! 10/10 :))

Rarely old keyboard review and repair in RU-vid, you will have more subscribers

Hi @keenonkeys, may I suggest to get rid of the beep noise, you perhaps try removing the capacitor to the left of the cpu beep track. I didn’t get a pss-100 from ebay (seller cancelled), but have a pss 80 and I am going to try removing this capacitor and also hack they keyboard matrix to see if I can get all the 16 sounds of the pss 100. Lovely videos ;)

The "detune" effect is actually pulse width modulation (I think).

You're born to be keyboard presenter

Show!!!! 🇧🇷😍🎹

OMG, it’s been about 30 years since I last heard the demo tune... -_-U before mine got broken. This tiny music cosmos of a device is printed in my brain. Back then perceived it’s sound in such a different way than I do now though... btw I’d love to hear it with fx, I bet it can yield some punchy sounds. Also there has to be a way to change the octave of the oscillators

Great videos. Where are you from?

Wonderful Demonstration! I love the way you enlarge logo and model number. Where can I get those fonts which look exactly like the real things on the key!?

11:22 - It's Pulse Width Modulation (PWM), but with limited duty cycle

sounds like 8bit RPG game OST ^^

oh man, i had one of these as a kid!!!!!D

I have a pss-125 that I want to mod with a power led, output Jack, and add a pt2399 delay circuit :) i'd like to cut out that little blip noise too. But this keyboard looks like a step up from the 125! More cool preset sounds!

Awesome Channel. Where do you purchase those switch contact jacks from?

Hi KoK! An amazing and brilliant demonstration as ever! I have the possibility to buy an PSS100…just one question: After doing some recording into the sequencer, is it possible to change with the Sound Variation controls the sound of the instrument for the melody? I think that it is not possible, but did you try it? Thanks again for your videos! 👍🏻👍🏻

Hey! Those presets are the same or similar to the VSS30 lol! I recognized them when you played the vibraphone. I do not have this model.. I feel cheated

Just bought pss100! I had pss80 in the past but this one is much better, the 8 additional presets with the variations and quite advanced sequencer. What baffles me is the lack of the output. Very strange considering all the other features. Yeah i know its easy to make, and i've made the outputs like that in the past, but still, WTF Yamaha.

I have a question. I have a PSS390 and PSS790 which I love, but they produce a very audible white noise when they're on. I used to also have a hum issue which I fixed by using an isolated guitar pedal power supply, but my guess is that the hiss/static comes from old transistors. I've identified a B1416 PNP transistor that seems to be an audio frequency output stage transistor. Would this be the right one to replace? There's also a MOSFET LM340T5 which seems to be an output regulator with noise elimination characteristics. I have never had to deal with removing a hiss, but this seems like a good place to start, right?

Hello, ive been looking for the service manual of the casio sk-10. do you happen to have it?

Just tried doing this mod myself (with the same exact jack) and I’m running into an issue that isn’t making much sense to me. When nothing is plugged in, the sound plays out of the speaker just fine, but when I plug a cable into the output, I get no signal at all. I thought it could be a soldering issue, but seeing as the sound is still making it to the main speaker, I don’t think that’s the case…

Where is there a PDF of the magazine scan?

Yamaha Mk100 next, please :)

Nice ! Is it possible to put a tonewheel on such keyboards ?

I have the PSR-780 but it's missing some screws, do you know where I can buy them?

Heh, nice Rockford Files theme there :P

Sounds exactly like old videogames

I've looked at this keyboard again and again and I can't shake the feeling that I need it in my life. Also, how do the voice variator's "Bright" and "Mellow" buttons affect the sound of the organ? Does it sort of sound like you are adjusting the drawbars/stops of an electric organ as you change the sound using the variator?

Can anyone provide a link to a US supplier for that output jack? Thanks! 👍

You can't beat the PSS Portasound keyboards.

Bummer that it doesn't record the variations. Cool keyboard nonetheless

The 1970s TV show theme at 7:55 was driving me crazy. It took some Googling to figure it out. (Answer is The Rockford Files.)

It sounds like a commodore-64 soundchip

Is it worth upgrading over a pss-125?

It sounds like a Sega Master System 😀👍

Yamaha psr 51 please

The demo song on this keyboard sounds very much like a NES or Commodore 64 game.

Hi, could you please tell me which signal is the "Amp" one (from your recording of both signals)? That one seems to have better sound. I think I want to just do a mono output and choose the better signal, but I am confused about which one is which. I would preferably like to avoid soldering to that spot on the board, but if that's the best way to get the sound to output clearly, I will give it a try. I just picked up a PSS-100 with a cracked case so there's not too much to lose. Also, you showed an output jack at the beginning that is capable of cutting the speaker signal when a cable is inserted. Does that enclosed output jack do the same thing? I would like to copy your modification if I can because it looks very clean and I don't want to worry about clearance with a the limited space and the added width and extra exposed metal contacts of the standard jacks. Thank you in advance if you can help me!

This sounds like a sega master system.

the detuned sound of Honky Tonk sounds like Pulse With Modulation actually. Is that possible?

10:58 Interesting, the mandolin's doing the weird repeating-note thing that one sample on certain toy keyboards does...

Piano reminds me of Ultima

@Keen On Keys this works for pss-130 just got one and bummed no audio output!! Please help!!

I have a pss80 and i believe is a 6 voice and i believe the pss100 is 8 voice.

Sounds like Many nes games use this keyboard or tone generation process

You should have way more subscribers than this!

真希望有人能采样这个键盘 出一个kontakt的版本😭

What type of wiring is that? I’m trying to order some and don’t want order the wrong stuff

15:10 sounds so NES haha and 17:11 is like Game Boy

WHEN ARE YOU GOING TO DO THE MT-40>>>>????????

Almost every single tone sounds like master system or the nes

Stefan is that you??

I have a suspicion that this guy is German. And it's not because of the accent. Btw, great vids.

These keyboards don't deserve such well-produced videos.