Spirit folio 14/2 schematic

bfisk

Member
2004-08-02 11:34 am
London
Hi all,

I'm trying to find the schematic for this mixer. I've seen the 10/2 one in another thread but there are some subtle differences between the two.
Also does anyone know if it's possible to obtain the 3 way power plug as a seperate item? I haven't tried Soundcraft as yet but I suspect I'll have to purchase a whole PSU and I dread to think how much it mght be.

Cheers
Bob
 

Netlist

Ex-Moderator
2003-01-18 9:50 am
I recall having problems with the input jacks of a spirit. When no jack is connected, they are supposed to terminate the input to ground, what we call a normally closed contact. Due to aging some contacts fail to close and can cause hum. I usually located the problem by plugging a jack in and out of all inputs and other female jacks while listening to the output.

/Hugo :)
 
Soundcraft won't provide a schematic?

Any chance the hum is due to the three pin power connector? That is a transformer winding with center tap, so if one of the end pins loses contact you are running half wave in the power supply. Plenty of hum if that happens.

I have not seen that connevctor elsewhere, but nothing stops you from lopping it off the adapter cord. Then mount a connector of your choice on the mixer chassis and its mate on the end of the power adapter cord.

If channel inouts are humming, you can isolate them by bringing the channel faders to zero. If the hum goes away with it, then the channel is at fault. If it hums with all channel faders at zero, then the hum is in the master section or the power supply. If the hum is on all outputs - subs, masters, aux sends, etc, then it is likely the power supply, and see my idea on that above.

If wiggling the power cinnector makes a difference, then it is loose.

From the what harm can it do department, if the female three pin connector on the power cord is loose, it is molded out of something rubbery. And the pins are split across the narrow dimension. if you grip the plug in stout pliers and squeeze a bit, you can tighten up the pins.