modding Soundcraft Ghost ???

[matthias]

Hi

I just looked at the schematics of the soundcraft ghost desk
and think of doing some mods on mine (24channel)...

1) there are a lot of ne5532 and tl072 opamps in there...
do you think it would make sense to swap them out to better types,
like opa2604 or just swapping the tl072 to ne5532...??

2) I found a lot of electrolytic capacitors in the sinal path...
changing them to better types, like panasonic fc series, or elna
electrolytics would provide a better perfiormance here...???

3) the master insert is unbalanced... I use it a lot , so I think a simple
transformer upgrade would do the job... what do you think...??


you can find the schematics in that thread:
http://www.groupdiy.com/index.php?topic=6280&start=15


btw: If you trace the connections of the line input jack along to the connector to the input section on page2 of the schematic... I find out, that the positive signal goes to the tape+ and the negativ signal to ground...
Is this correct?? I always thought, the input was balanced ??


thanks,
mat

 

[Svart]

it's doesn't go to ground, that arrow is part of the line/mic switch.

as far as modding, that thing DOES have a lot of caps in the audio path.

You would be best going to nichicon HE caps if you intend to only recap.

You *could* possibly remove the caps in the system by switching out the BJT input opamps (like NE5532) to a FET input like the opa2604/opa2134.

I would try replacing two channels of opamps with the opa2604 and testing. then remove some of the coupling caps and seeing what happens. normally you would get hella dc offset problems, but the FET inputs tend to negate that.

ultimately your ears will be the judge, but if you are like me, very anal about the fewest parts in the audio chain normally(unless they have very good reason to be there..).