Yamaha cs50

[claudiopallone]

Hi guys.

I don't know if I have done a great or a really bad deal.

This morning I bought a Yamaha cs 50 in marketplace.
It was going for 50Euro (wtf) because not in working condition. I have quickly agreed with the seller to get it for 600 Euro because I knew he would get bombed. So I closed the deal.

I went to get it, looked inside and at least it didn't look empty haha. It seems like the main parts should be where they are. I am no expert and that's why I m here, but the biggest flow I could see is that all cables going to the keys had been cut.

Now before I give you photos and before I know that it could be other 100 problems other than this, I would like to ask you. Why do you think the previous buyer had cut all cables going to the keys ? What project did he have in mind ? I am asking because I think that could help figure out what other kinds of problems the machine has.

I thank you in advance for your help and sorry for my English

All the best .
Claudio

[madtheory]

Preparing it, in a very rough and brutal way, to be sold for parts?

[claudiopallone]

Oh no ... Why do you say so

[claudiopallone]

Preparing it, in a very rough and brutal way, to be sold for parts?

Mmm... would you start by cutting those ?
I can't be that they have been "dragged off" accidentally by lifting the keybed ? Still haven't had time to look at it but I saw that the keyboard could be lifted / removed without removing the main panel ?

[madtheory]

Oh no ... Why do you say so

Because the CMOS chips will be rotting by now. The key assigner is a common failure. Only way to get one is break another CS poly. If you are lucky, you can bypass the key assigner with the Kenton retrofit kit. Play the synth via MIDI only.

I can't be that they have been "dragged off" accidentally by lifting the keybed ?

A photo would tell.

[claudiopallone]

I could finally look inside a little , and even though my poor expertise I kind of feel I have just thrown 600 Euro in the water. Could some expert tell me a little more here? I get zero sound from outputs obv

Here the photos https://drive.google.com/drive/folders/ ... cq7-P7Q39s

All the best .
Claudio

[claudiopallone]

I ve got some information from the seller , he said that the owner 20 years wanted to use the keys for another project but never he never kept going so could be that the rest is in shape

[ppg_wavecomputer]

Oh no ... Why do you say so

Because truth always hurts, and reality tends to bite back viciously.

In Yamaha custom parts parts alone, it would easily be worth three or four times the price you paid for it. After all, more CS50s than I care to admit were cannibalised for parts to make their bigger brethren survive.

One major and very common pitfall with CS polysynths are the 4XXX CMOS ICs as well as the keyboard assigner ICs. The latter can be salvaged from some contemporary top-of-the-range Yamaha organs if space is not an issue for you. I had all the 4XXX ICs replaced as well as various capacitors and tantalum caps some years ago, just to make sure they would not get me in trouble eventually.

Unfortunately, I can't blow up the photos and have a closer look at what is inside but it looks reasonably complete.

This is yet another story of an apparent bargain turning sour.

Stephen

[claudiopallone]

Oh no ... Why do you say so

Because truth always hurts, and reality tends to bite back viciously.

In Yamaha custom parts parts alone, it would easily be worth three or four times the price you paid for it. After all, more CS50s than I care to admit were cannibalised for parts to make their bigger brethren survive.

One major and very common pitfall with CS polysynths are the 4XXX CMOS ICs as well as the keyboard assigner ICs. The latter can be salvaged from some contemporary top-of-the-range Yamaha organs if space is not an issue for you. I had all the 4XXX ICs replaced as well as various capacitors and tantalum caps some years ago, just to make sure they would not get me in trouble eventually.

Unfortunately, I can't blow up the photos and have a closer look at what is inside but it looks reasonably complete.

This is yet another story of an apparent bargain turning sour.

Stephen

Thanks for the reply! It seems like what's missing are the KAS and SH cards below the keyboard. Will they be hard to find ? In case I would like to sell it in parts, where would you recommend doing that ? Thank you in advance

[madtheory]

It's cosmetically perfect, and no signs of corrosion, even the caps I can see look minty. I notice some tomfoolery on the PSU. I doubt those parallel resistors are factory. But I could be wrong. But the soldering is horrible.

Will they be hard to find ?

Yes.

In case I would like to sell it in parts, where would you recommend doing that ? Thank you in advance

Reverb.com, Ebay.

If you want to use it as an instrument, contact Kenton. I am pretty sure their retrofit bypasses the KAS. But ask them.

[ppg_wavecomputer]

I strongly endorse trying the Kenton option first before gutting the instrument -- the lure of quick profit, I know.

Stephen

[claudiopallone]

I strongly endorse trying the Kenton option first before gutting the instrument -- the lure of quick profit, I know.

Stephen

One local technician told me that the midi implementation won't work without those boards...I Think I will give it a try anyway.

[synthRodriguez]

You need all the original boards and a working synthesizer for the Kenton system to work, it piggybacks onto the key assigner. Without the KAS and SH cards, it's useless.

If all the Yamaha chips are on the voice cards, I'd say you got a good deal. I certainly would have snatched it up for $600. It's really not that bad if you know what you're doing and the only thing that is missing is the two boards.

Would love to get it working for you, too bad I'm in the states.

[ppg_wavecomputer]

I'll have a spare voice board then. Or maybe two, if the price is right.

Stephen