After some investigation, the reason why the accompaniment potentiometer is stepped like that is because there's only 5 output states for both L and R (pins K020 and K021) on the lower CPU (UPD938G). Since the lower CPU outputs ONLY a single serialized 16 bit audio signal (time shared to emulate stereo) the accompaniment potentiometer tells the CPU to internally attenuate the levels of the percussion (and presumably bass) by simply having identical samples at 5 different volume levels, hence the 5 selectable states. The only real way to isolate the percussive PCM samples and retain full function would be to literally duplicate the entire circuit with an additional UDP938G or equivalent. You'd need to basically redirect all K014 and K015 inputs to the new CPU along with K020 and K021 for the 5 output levels (you could go technically add an L/R pan pot due to how the mode switching works on the CPU). You can then isolate the output to an additional separate DAC circuit in order to retain the independent output. You should be able to feed this signal back into the main mixer circuit (with some filtering of course) and the unit SHOULD behave normal and in stock configuration upon using the regular speaker/headphone outputs.
That doesn't sound right, five samples the same would make no sense. I could see it doing something like bit-shifting right from 0 to 4 steps, which would give a nicely exponential response simulating a log volume pot.
I like to put masking tape over the screws so I don't have to remember which ones go to those holes on the body. Saves you a lot of headache later on down the road
Great video and mods Simon! Just an FYI, the DM100 isn't the only double manual that Casio ever made. There is also the 1983 Casiotone Symphonytron 8000 that though a modular system, could be had with two upper manuals and also bass pedals. A very rare system, with apparently only 100 ever made. Looking forward to seeing you do the clock mod and more with your DM100!
You could probably make some key weights by taping a short stack of coins together, and then using something like modeling clay to keep it from rolling. Basically embed the cylinder in some thing square or triangular. Might even be heavier than those batteries for its size. That could avoid putting lateral stress on keys from the other mentioned jamming methods of keeping keys down. That's because I know some Casio keyboards used a flex hinge, which would be tricky to fix if it breaks. I taped down a few keys on an SK-1 as a fix back when I had it because of the flex-hinge breaking, but it made playing those keys kind of sloppy or inconsistent.
If I remember correctly, all the lower keyboard stuff goes thru the same D/A-converter, so separating the accompaniment would be a challange. However, there are lots of possible hacks for the upper keyboard such as sample memory expansion, analogue filters, a bit of envelope control and better input options for the sampler... With separate filters for each voice the upper keyboard would become like a low-fi sampling TimbreWolf! Just add real simulated wood grain sides and some heavy distorsion! :-)
@@nmusic65 I used two UMR2 MIDI retrofit kits, one for each keyboard. I did it a long time ago and can't remember where I got all the info on how to do it but you should be able to find it on the internet
i just learned out people modding korg volcas to have multi outs, its useful on the drum machines and stuff to get the toms and snare seperate in the recording mix, i really might do it
magpie. I cant wait. I got the little brother (without the sampler) of this and my attempts at clock speed mod have all failed, I cant find the resistor! hope you are able to figure it out! I modded mine with a patch bay, I get some CRAZY sounds outta that thing. sheers magpie.
Ooh nice with patchbay! The clock on these are coils. I have never done a swap with a coil before so will be interesting 😅 But essentially you replace an oscillator rather than a resistor. So it is a bit more advanced. You can look up LTC1799 (thats the easiest choice I think), and circuitbenders.uk
Instead of the battery trick you can use cigarette filters stuck underneath the key next to the one you want pressed and they will hold down in press the key you want
Using guitar picks or flippos/tazos/pogs (remember those?) to put on a key and under the neighbouring keys is easier than batteries or other weights. Doesn't work on the top and bottom key though.
@@SimonTheMagpie That might work too, but I just lay them flat on the key I want to press, and under the keys next to it. Strictly a white key thing, of course.
maybe a little keyboard latch circuit would be a good addition to the top keyboard :) The batteries did produce some pretty good happy accidents though tbh. I eagerly await the big knob mod, clock/sample rate reduction is where the magic is. Sometimes. Mostly. Also - the soldering light which also sucks, is it expensive and where does the results of the suck get routed, hose out the window? I have a lot of de-soldering and soldering to do and I'd prefer not to die from inhaling the fumes. Really enjoying the renewed energy for making videos, hope you're having fun!
Ooooooooh SMART!! Just a ton of switches to solder but maybe totally worth it. One switch for every key on the upper keyboard. Will totally do that. Just gotta see if I can fit it in a cool looking way. The whole cone with a light is something I made myself and attatched to a classic solder extractor that showed up in the trash 😅 Also the solder fume sucker itself is modified so it more or less is just a vacuum cleaner with a really long pipe going up into the ceiling and out the room. So it doesnt have a filter anymore which costs a ton of money and needs yearly replacing or something like that.
@@SimonTheMagpie ah I was hopeful there was a simpler way rather than a switch for every key, latching the gate signal with one switch so you hit a few keys and the key off is not registered. Diode on that circuit that you can switch in and out? Latching it at the keyboard multiplexor (if there is one) rather than the key end of the circuit? Apologies if all of that is absolute nonsense. Maybe heavier batteries is the smart hack :) Thanks for the info on the solder sucker, will keep an eye on the trash :D
not related to the video, but i feel like you are the only person who could potentially find a solution i like playing keys: piano, synths and so on but i also want to play in camp settings, aka, when i go to the beach, some people bring guitars and it’s an instant vibe, but when it comes to keys i cant find a single comfortable solution do you think you could design an instrument that is like a portable piano that works acoustically and you can sing along to?
I would assume since it sounds pretty much like a MT-540 which I still have hooked up in my MIDI chain (lol) that it is M ostly P oor E xperience capable. 😜🎶🎹🎶🎶 Play On
After some investigation, the reason why the accompaniment potentiometer is stepped like that is because there's only 5 output states for both L and R (pins K020 and K021) on the lower CPU (UPD938G). Since the lower CPU outputs ONLY a single serialized 16 bit audio signal (time shared to emulate stereo) the accompaniment potentiometer tells the CPU to internally attenuate the levels of the percussion (and presumably bass) by simply having identical samples at 5 different volume levels, hence the 5 selectable states.
The only real way to isolate the percussive PCM samples and retain full function would be to literally duplicate the entire circuit with an additional UDP938G or equivalent. You'd need to basically redirect all K014 and K015 inputs to the new CPU along with K020 and K021 for the 5 output levels (you could go technically add an L/R pan pot due to how the mode switching works on the CPU). You can then isolate the output to an additional separate DAC circuit in order to retain the independent output. You should be able to feed this signal back into the main mixer circuit (with some filtering of course) and the unit SHOULD behave normal and in stock configuration upon using the regular speaker/headphone outputs.
I will pin this thank you 😁😁
One Correct Answer, To "Time Shares". = "No."
This, may save you thousands of denominations of funds. Have, a fund time.
That doesn't sound right, five samples the same would make no sense. I could see it doing something like bit-shifting right from 0 to 4 steps, which would give a nicely exponential response simulating a log volume pot.
that little jam at the end was beautiful
Prancing around a maypole and he still manages to get a video posted!
I like to put masking tape over the screws so I don't have to remember which ones go to those holes on the body. Saves you a lot of headache later on down the road
Smart! Will very much do that from now on 😁
At least when it has deep holes like this
pro tip !
14:18 battery falling sounded like a drum fill :)
Jamming with electric ghosts 😆
asynchronus alkaline accent
Nahh, it was way too full sounding to be a Casio drum sample.😜
Nahh, it was way too full sounding to be a Casio drum sample.😜
Great video and mods Simon! Just an FYI, the DM100 isn't the only double manual that Casio ever made. There is also the 1983 Casiotone Symphonytron 8000 that though a modular system, could be had with two upper manuals and also bass pedals. A very rare system, with apparently only 100 ever made.
Looking forward to seeing you do the clock mod and more with your DM100!
Glad to see channel doing well Magpie 🐐
You could probably make some key weights by taping a short stack of coins together, and then using something like modeling clay to keep it from rolling. Basically embed the cylinder in some thing square or triangular. Might even be heavier than those batteries for its size. That could avoid putting lateral stress on keys from the other mentioned jamming methods of keeping keys down. That's because I know some Casio keyboards used a flex hinge, which would be tricky to fix if it breaks. I taped down a few keys on an SK-1 as a fix back when I had it because of the flex-hinge breaking, but it made playing those keys kind of sloppy or inconsistent.
If I remember correctly, all the lower keyboard stuff goes thru the same D/A-converter, so separating the accompaniment would be a challange.
However, there are lots of possible hacks for the upper keyboard such as sample memory expansion, analogue filters, a bit of envelope control and better input options for the sampler...
With separate filters for each voice the upper keyboard would become like a low-fi sampling TimbreWolf! Just add real simulated wood grain sides and some heavy distorsion! :-)
3:10 😂👍🏻 Wonderful experiences here with you again! ⭐⭐⭐⭐⭐
It's also possible to add MIDI I/O on it!
that'a what I want to do, can you recommend some website that show you how? this kit with midi would be outstanding.
@@nmusic65 I used two UMR2 MIDI retrofit kits, one for each keyboard. I did it a long time ago and can't remember where I got all the info on how to do it but you should be able to find it on the internet
Love that battery drum fill at 14:18 . Sample it! ⭐️⭐️⭐️⭐️⭐️
@14:01. "And you may find yourself living in a shotgun shack...."
i just learned out people modding korg volcas to have multi outs, its useful on the drum machines and stuff to get the toms and snare seperate in the recording mix, i really might do it
magpie. I cant wait. I got the little brother (without the sampler) of this and my attempts at clock speed mod have all failed, I cant find the resistor! hope you are able to figure it out! I modded mine with a patch bay, I get some CRAZY sounds outta that thing. sheers magpie.
Ooh nice with patchbay! The clock on these are coils. I have never done a swap with a coil before so will be interesting 😅
But essentially you replace an oscillator rather than a resistor. So it is a bit more advanced. You can look up LTC1799 (thats the easiest choice I think), and circuitbenders.uk
Sounds great and what a follow up.
Instead of the battery trick you can use cigarette filters stuck underneath the key next to the one you want pressed and they will hold down in press the key you want
Using guitar picks or flippos/tazos/pogs (remember those?) to put on a key and under the neighbouring keys is easier than batteries or other weights. Doesn't work on the top and bottom key though.
Smart! Sticking the pogs in between keys?
@@SimonTheMagpie That might work too, but I just lay them flat on the key I want to press, and under the keys next to it. Strictly a white key thing, of course.
maybe a little keyboard latch circuit would be a good addition to the top keyboard :) The batteries did produce some pretty good happy accidents though tbh. I eagerly await the big knob mod, clock/sample rate reduction is where the magic is. Sometimes. Mostly. Also - the soldering light which also sucks, is it expensive and where does the results of the suck get routed, hose out the window? I have a lot of de-soldering and soldering to do and I'd prefer not to die from inhaling the fumes. Really enjoying the renewed energy for making videos, hope you're having fun!
Ooooooooh SMART!! Just a ton of switches to solder but maybe totally worth it. One switch for every key on the upper keyboard. Will totally do that. Just gotta see if I can fit it in a cool looking way.
The whole cone with a light is something I made myself and attatched to a classic solder extractor that showed up in the trash 😅
Also the solder fume sucker itself is modified so it more or less is just a vacuum cleaner with a really long pipe going up into the ceiling and out the room.
So it doesnt have a filter anymore which costs a ton of money and needs yearly replacing or something like that.
@@SimonTheMagpie ah I was hopeful there was a simpler way rather than a switch for every key, latching the gate signal with one switch so you hit a few keys and the key off is not registered. Diode on that circuit that you can switch in and out? Latching it at the keyboard multiplexor (if there is one) rather than the key end of the circuit? Apologies if all of that is absolute nonsense. Maybe heavier batteries is the smart hack :)
Thanks for the info on the solder sucker, will keep an eye on the trash :D
bend it! bend it! bend it!
not related to the video, but i feel like you are the only person who could potentially find a solution
i like playing keys: piano, synths and so on
but i also want to play in camp settings, aka, when i go to the beach, some people bring guitars and it’s an instant vibe, but when it comes to keys i cant find a single comfortable solution
do you think you could design an instrument that is like a portable piano that works acoustically and you can sing along to?
awesome
You’re so damn amazing 😁👍
Ha en bra midsommar!
number one,,,always!
3:06 since they like hiding in carpet just put some on your work bench, then they will not go bouncing all over the floor and vanishing. LOL!
That ending...
Is it MPE Bro?
What is mpe?
@@SimonTheMagpie Magical Playing Energy
I would assume since it sounds pretty much like a MT-540 which I still have hooked up in my MIDI chain (lol) that it is M ostly P oor
E xperience capable. 😜🎶🎹🎶🎶 Play On
The MT sounds don't seen to match with the SK-sounds in this keyboard.
Dope
Found one of these for $8 at Goodwill. It was cool but not worth the crazy prices they go for these days considering that SK-1s are still affordable
Exactly. I have a DM-100 too, and while I do like it, it IS only two ordinary Casio keyboards stacked in the same case.
9 Volt Latch… band name… t-shirt… both 🤔
Orrrrr u pull the screws up prior to flipping
Bro I have the same keyboard bro I'm from India bro pls send your mail bro I want to contact you.❤❤❤😊