X77 troubleshooting

[SirLordJason]

Hi All!

I bought an X77 + X77L not too long ago, i think they're very interesting and i don't see them popping up all to often so i grabbed this one for what i consider fairly cheap even knowing it would probably need some work. As it happens, it needs some work (haha). I had to locate a leslie cable for it which took a while, and then spent a bit getting oiled and running smooth. The leslie is still a bit noisey which brings me to my first question. There is a very obvious place for oil on the horn, but the noise seems to be coming from the middle motor/rotor/pulley assembly, is there somewhere to oil this part?

Beyond that im not getting any sound aside from a mild ground hum that goes away or lessens with various configurations of the main only/echo only/ celeste / chorus tabs. So i imagine my next step is to get in there and clean every contact. To that end is there anywhere in particular i should start? The fact that im getting an obviously amplified hum through the speakers leads me to believe that my problem is somewhere in the organ yes? And to get specific is it best to actually unseat each of these little pin connectors and give them a spray and reseat them? Another very rudimentary question, which output is the main? i cant find a schematic or manual and the label is worn off there.

Also, i have read through a good amount of the X77 related posts here (including the really long one), they have all been informative but i figured i would start this thread to see if anyone had any specific tips that might save me some extra work :) Eventually i will need to replace some keys as well, does anyone know what the easiest way to get at the manuals is? (also i should check to make sure theyre both connected, any tips there?)

Anyways, any help is much appreciated, im very determined to get this thing in playing shape!

[Tim Rinkerman]

Are you getting any notes at all, or just hum? Is the tone generator in the organ actually running? It has to be turning to make sound. The X-77 leslie has more things turning inside it than most cars..top rotor, bottom rotosonic drum, and a few pulleys on the space generator... plenty of places to make noise. I had one for quite a while and got to know its problems pretty well. The keyboards take quite a bit to disassemble far enough to change keys..you start at the top and unbolt levels till you get to the keyboards. And yes, clean every contact and edge connector. Good luck!
P.S. The main output is the right side one..looking at the Leslie outputs on the organ..

[ubxf]

I found that the switches, tabs were a major source of problem. Deoxit and exercise helped quite a bit but still not perfect.

[SirLordJason]

Thanks for the info!! Just hum no notes at all yet. The TG certainly appears to be moving, It was doing so very loudly until all the oil worked its way in. The noise in the leslie seems to be from something rubbing intermittently in one of the wheels that drives the space generator. Ill begin cleaning this week and see if anything changes :)

[SirLordJason]

Thanks for info!! No sound other than the hum. The TG certainly appears to be spinning (it was doing so very loudly before the oil soaked in). The leslie noise seems to be coming from some intermittent rubbing of elements near the space generator. Ill give all the tabs a good cleaning as well as the contacts and hope for the best :)

[Admin]

Since there are four separate channels on this organ, the fact that there is no sound at all points to something common to all of them as the problem.

First, the obvious: you must have a preset key pressed on each manual in order to hear any sound. If you have pressed the A# or B preset, you must have drawbars pulled as well. I know this is basic knowledge, but there was a post here a while back with the same problem, and the presets were the issue.

The next thing to do is to determine whether the problem is with the console or the Leslie. Measure the voltages from the power supplies in organ and speaker and verify that they are correct. Be careful working with the Leslie. The space generator uses a high DC voltage that will give you nasty shock and is present for quite some time even if the unit is off and unplugged.

[SirLordJason]

Yes i had initially wondered if there might be a main preamp that all the channels run through before going into the speaker that might be the problem? I had tried many combinations of the preset keys and drawbars with no avail, is it also possible the entire manuals are disconnected at a single point? Other notable clues, the chorale and celeste tabs seem to function properly in terms of slowing/speeding up the horns.

[Admin]

Yes i had initially wondered if there might be a main preamp that all the channels run through before going into the speaker that might be the problem?

No. There are separate pre-amps/line amps for each channel. Check the power supplies.