(New member) Electone CSY2A fx loop and other mods

[Kavalcade]

Hi organ folks,

Si I am new to this wonderful forum. I had a greaaaat lot of inspiring reading so far and I intend to make my contribution to the organ world the best I can.

What brought me here in the first place is that recently got a nice yamaha Electone CSY2A(E), absolutely free. It is in overall great shape, all sounds are clean and working fine, except for the synth section. It is the same problem mseven described in the Yamaha SY-2/CSY-2A Modification and Repair thread a little while ago. The synth is retriggering over and over when on manual but not on the pedal.

Of course I plan to spend all winter modifying it to more I can and as much as my finances allow me! But I will certainly need help from some of you guys to get to that. I manage to get the service manual from Magnus, thanks to him. So i feel like I'm on business. But wait! i still have some "schematics dizziness" going on. But I am a fast learner, so I should be on my feet soon enough.

All right, now let me describe the few first mods I'd like to do and those of you who can be of some assistance, please manifest yourselves.

1 : Change the RCA output plug for a 1/4" plug. That shouldn't be too much headache.

2 : I want to make 2 different FX Loops. First one is a send to my effects and return back to the organ's amp. Either the overall sound or two different paths (the 2 manuals in one and bass pedal in the other). Then I can use reverbs, delays, dist, etc.

So my question here is where, in the organ's signal path, do I need to operate in order to do that. Also, will the signal impedance be friendly with my pedals and back to the amp?

3 : the second FX Loop is for my Leslie emulator, a Boss RT-20. I would like to be able to assign which manual go through it, the same way it is already configured with the built in leslie speaker. It means I want to be able to assign the manuals independently using the existing rotary switches on the organ (upper and lower voice). How do I do that? (later on, I'd like to modify my RT-20 so I can change it's rotary speed with the organ's speed switch. But not a priority)

4 : Bypassing the synth's presets. For that i already downloaded the document "Ho to build your own son of GX", designed for the E70 but which I think can be adapted easily to the CSY2A's circuitry. I'll start by trying it as is, then I'll post something new to share my plethora of inspiring bugs!

5 : What else??? I think this one is for next summer. Taking off all the top section to make it transportable. With all my upgrades, I could now put it on a keyboard stand and plug the whole thing in the pas system, leaving the speakers comfortably at home.

That's about it for tonight's ideas.

[Guest]

Most of your mods are introducing/replacing simple patch points, so just a matter of tracing the audio path and interrupting with a normally closed jack where desired.

As far as I recall, the external Leslie speaker connector on the back of the synth will give you the audio patch points fed off the 'leslie' panel switches - careful as there is also power on adjacent pins - the pinout is in the manual, so not too hard to follow (?). You may have to add/make your own separate connector if you can't find one compatible with the existing one on the back of the cabinet.

As far as audio levels - haven't got a solid answer, though I did tap into the manuals, to divert them to the synth filter, the levels seemed very low, leaving me to believe it was not the optimal point, but then I was just 'hacking' at that point and not committing to a hardwired connection and so just boosted their levels using an opamp.

Again, you'll have to trace the audio path which may lead you to the reverb/mixer board - hopefully a good enough clue for now. Unless you have a scope, you will have to probe with an an audio amplifier to check the signal levels - use a small capacitor 0u1 to block any DC voltages and be sure to not short anything. The one thing that MSeven mentioned is that the output stages are noisy, so you have to find the optimal point to patch into, having a good audio level, otherwise, you may have to amplify them using an opamp etc.

As far as retriggering, you have to clean the metal keyboard contacts of the upper manual. Basically undo the two screws on either end of the keybed - underneath where your knees bump up will be where you'll see them. You also have to pop the lid (two screws on top), then everything flips up for servicing. There will be a white styrofoam cover over the keybed contacts, carefully pop that out and away from the retaining tabs, to reveal the stacked key contacts.

The contacts are all metal, I cleaned the contacts using 'Deoxit' made for switches, you may want to use a special cleaning swab with a fabric pad that does not catch as would fibers from a Q-tip. Gently clean each contact area (buss bar as well), being sure not to bend anything. You also have to work each key a few times to ensure the contact surfaces are properly conditioned with the contact cleaner. You can spray them, but mind you will have to cover where you don't want the spray to go.

That should hopefully fix the retriggering - assuming it's a contact issue, since you say the pedal contacts (a different form of contact, being much larger) work fine? Otherwise, if there is an electronic issue, it could cause false triggering of the envelopes due to a bad transistor etc. Anyway, you should confirm that the pedal note control works as you mentioned, without multiple triggers.

The reason for the multiple triggers is that the circuit looks for transitions in the key voltage, any dirt will make a noisy contact and result in multiple triggers - it's the same for any mechanical contact, requiring you to clean the related surfaces.

I did 'chop' a CSY-1 which detached the top and left off the 'leslie' and required mounting the power supply and amplifier assy - the speaker was detached as well, making it necessary to plug into the overall output to access the final audio that would normally feed into the power amp (via an RCA plug if I recall).

So it is doable, but you still have a bulky top since it has both manuals and all the related cards - better on the CSY-2AE as all the cards are in the top area and do not drop down into the speaker cabinet area - the CSY-2AE is much easier to work on since the cards are flat and the wire points are labelled. Careful when poking around as the metal rails used to mount the cards are also serving as power distribution for the DC supply.... you can short these out if you have a scope ground lead touching them.

Hi organ folks,

Si I am new to this wonderful forum. I had a greaaaat lot of inspiring reading so far and I intend to make my contribution to the organ world the best I can.

What brought me here in the first place is that recently got a nice yamaha Electone CSY2A(E), absolutely free. It is in overall great shape, all sounds are clean and working fine, except for the synth section. It is the same problem mseven described in the Yamaha SY-2/CSY-2A Modification and Repair thread a little while ago. The synth is retriggering over and over when on manual but not on the pedal.

Of course I plan to spend all winter modifying it to more I can and as much as my finances allow me! But I will certainly need help from some of you guys to get to that. I manage to get the service manual from Magnus, thanks to him. So i feel like I'm on business. But wait! i still have some "schematics dizziness" going on. But I am a fast learner, so I should be on my feet soon enough.

All right, now let me describe the few first mods I'd like to do and those of you who can be of some assistance, please manifest yourselves.

1 : Change the RCA output plug for a 1/4" plug. That shouldn't be too much headache.

2 : I want to make 2 different FX Loops. First one is a send to my effects and return back to the organ's amp. Either the overall sound or two different paths (the 2 manuals in one and bass pedal in the other). Then I can use reverbs, delays, dist, etc.

So my question here is where, in the organ's signal path, do I need to operate in order to do that. Also, will the signal impedance be friendly with my pedals and back to the amp?

3 : the second FX Loop is for my Leslie emulator, a Boss RT-20. I would like to be able to assign which manual go through it, the same way it is already configured with the built in leslie speaker. It means I want to be able to assign the manuals independently using the existing rotary switches on the organ (upper and lower voice). How do I do that? (later on, I'd like to modify my RT-20 so I can change it's rotary speed with the organ's speed switch. But not a priority)

4 : Bypassing the synth's presets. For that i already downloaded the document "Ho to build your own son of GX", designed for the E70 but which I think can be adapted easily to the CSY2A's circuitry. I'll start by trying it as is, then I'll post something new to share my plethora of inspiring bugs!

5 : What else??? I think this one is for next summer. Taking off all the top section to make it transportable. With all my upgrades, I could now put it on a keyboard stand and plug the whole thing in the pas system, leaving the speakers comfortably at home.

That's about it for tonight's ideas.