Unlocking the Yamaha E70

[Ray Fenwick]

[Ewaves]

Hi Ray

Big difference E70 have 2 oscillators per voice, where E50 have 1, just like CS80 , and for the rest what you saying, they're fairly similar, just not everything populated.
Grossing it with a D80 is a good idea, D80 have the same kind of PASS for there oscillators, even the same keyboard scanning, maybe you can double your oscillators !
At least have some spare chips !

[Ray Fenwick]

Hi Ewaves
That sounds encouraging Everything for me is guesswork at the moment until I am in the same place with the organs and start looking inside, so every piece of information and advice is very useful, and much appreciated!

[Ewaves]

This is just a warning for every one who wants to mod this organ, especial the Cmos 4000 digital parts, be very careful with it, its one of the first generations and very sensitive for static voltage and mostly non-buffered, today's generations are better and still available .

Can not speak for the Yamaha-LSI's, but its save to earth yourself and the organ when working on it.

Saying that I never destroyed an I.C. with static voltage in my live, but better safe than sorry.

On youtube there's some one named itself " the dollar guy" and he is restoring his CS80, replacing all his Cmos 4000 series and a lot of other components , but some one must decided for himself if that's the way to go.

And also be Shure you have the right knowledge and measuring equipment , some parts are not available anymore.

[Ray Fenwick]

Sound advice, thanks.

[Guest]

From old Alvek post "E50 has 1 OCS per voice, but it's not a problem, You can put in dual lower keyboard and it will be 2 absolutely independent OCS, which actually even better than E70, anyway "

To be sure, Adamstan is particularily knowledgeable on the E50. You can find his related posts on other sites as well as ours.. : http://forum.vintagesynth.com/viewtopic.php?f=1&t=52194

OrganForum "Posted by adamstan
Hello again, I've done another mod to my E50.

Yamaha decided, that sine wave is too boring for drawbars, so each "flute" sound is made of fundamental, and 1st overtone mixed in at around -10dB. (So 16' is actually 16'+8' etc). I don't like it - if I want these overtones, I'll just engage next drawbar - so I removed some resistors from "FWM" and "IF" boards, and now each flute is sine."

[Ewaves]

Don't now what Alvek means with " it will be 2 absolutely independent OCS " , all OCS have the same time sharing, so both organs will sound the same on same conditions.

[Guest]

Don't now what Alvek means with " it will be 2 absolutely independent OCS " , all OCS have the same time sharing, so both organs will sound the same on same conditions.

I think he meant each manual has a different voice, layered together you get a similar approach to the CS80 dual-layered voice structure?

[Electradyne]

Hello! A user from the grave here. I was a member years ago (under a different handle), but had to drop out due to "life getting in the way".

Anyway, I'm about to dig in to the Son of GX mods on my E70. I have all the parts, cables, front panel graphics printed, etc. So there's no point in delaying the inevitable! (I'll post photos and descriptions as the project progresses.)

As an initial exploration into the guts of this machine, I'm hoping to increase the amount of detuning when using the celeste sliders. When maxed, it's a bit subtle for my taste. Any idea if this parameter is accessible?

Thanks!

[Electradyne]

The vinyl front panel graphics arrived today. (There's a protective translucent film on the front, so if you see any bubbles, they are simply under the film, and are not on the actual panel graphic.)

[Guest]

Congratulations - looks great. Good luck with the mods and be sure to post them here and on Youtube

The vinyl front panel graphics arrived today. (There's a protective translucent film on the front, so if you see any bubbles, they are simply under the film, and are not on the actual panel graphic.)

[ATTACH=CONFIG]29601[/ATTACH]

[ATTACH=CONFIG]29602[/ATTACH]

[Natron]

Hello Fellow enthusiasts, i am currently unlocking my E70. I am mostly done but have run into a few things. Concerning the pedal TPR 4 board, it appears there is no VCF 2nd decay clock. How does one access that?

[Ewaves]

Having this not done by myself, but looking in the schematics you can use the same value pot. and connected it the same way as in the upper/lower keyboards, it's only used in piano presets and therefore not used by pedalboard.

[Rustychops]

[Ray Fenwick]

Hello everyone.

Just to let you know that I am finally in the same place as my organs and can soon begin to look at this project. To remind you, I have an E-50, D-80 and D-85 to supply parts, plus a lot of parts from an E5-R that was scrapped - including lots of sliders and switches.

The plan is to integrate the D-80 solo synth in the E-50, with some other goodies thrown in. One change to the plan is that I'll have to 'chop' it, as my circumstances have changed a lot, and it must be transportable. So I plan to transfer everything into a CS80 style case and front panel, and use my RA-50 for amplification.

I like the Arduino idea - did it get any further?

This thread is great (I've just read all 75 pages again...) but many of the links to images are now dead - I wonder if the OP's are around and could refresh them?

All advice gratefully received, and glad to know that people are still interested in this project - there's some great instruments out there, and more to come!

Slightly late, but Merry Christmas to all!

Ray



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