Synth Fix

LektroiD · Joined: 26 Jun 2009 Posts: 11

The individual daughter-boards seem way out of calibration, and no matter how I tweak them they all sound different. However, if I use the same slot to put each daughter-board in individually, they all seem balanced. Therefore I would assume it is something to do with whatever is powering and controlling the boards. Any ideas would be kindly received.

sam · Joined: 14 Jun 2010 Posts: 2

Have you checked all connection to the power supply ...?

LektroiD · Joined: 26 Jun 2009 Posts: 11

I have it working to a point (PSU is working ok now), but some of the voices are extremely quiet now.

synthnut · Joined: 30 Oct 2010 Posts: 1 Location: UK

Hi,
Out of interest, what had happened to the PSU? Might it have taken some stuff with it if it failed?
You have the schematics I take it?
If you look at how the boards are bussed, some controls are just bussed to all six cards and then obviously some are individual.
A, D, S & R are bussed as is the VCF cut-off and Q CV plus the LFO and joystick VCF mod.
Check which parameters it is and then you should be able to pin point the area a little more.
Odd behaviour indeed though! Might it just be that the connectors are high resistance? Has the unit been somewhere damp or in storage a long time?
I too have a Stratus that has died and I'm suspecting the PSU and its caps but have yet to get it on the bench as the studio is a building site!

Cheers,
Ben

LektroiD · Joined: 26 Jun 2009 Posts: 11

My PSU died at one point, it was the fuse holder of all things. However, I found the CEM3310's were at varying stages of death, so I've parted it out, built a nice 4 pole resonant hipass out of one of the 3320's which is sitting happily in my modular just now. I think that's the best thing to do when CEMs start to die on these things. The PSU is now driving my modular too as it's more stable than the one that was in it.