Crumar Musical Instruments User Group.

Hi,

Just acquired a performer and am attempting to fix the following problems any tips would be helpful as i'm a bit of a newbie in repair and schematics.

Problems:

No main output
volume levels not responding
eq section not working
strings 8/16 not working although one of the two lights up

working:

brass section seems ok
crescendo/sustain seems ok
signal out ok-so I hear some strings this way
all keys work
mod section works
resonance ok although seems a bit off? perhaps some adjustment?

SO:  After studying the schematics I'm assuming the 1450/741 chips are bad since they seem to affect the strings/main section?
Im going to get some replacements and check it out. How about replacing caps? 
any help would be appreciated
cheers
T