Rhodes amp splitter

[jlullo]

Hey guys... the keyboard player in my band recently aquired a Rhodes Mark I 88.  He has the kind where a 4-pin cable goes from the keys to the amp.  The amplifier for it is also the smaller 2x12 cabinet, and not the suitcase model.

here is his post on the Rhodes Forum, which has more details on his model:
http://www.fenderrhodes.com/forum/viewtopic.php?p=12941&sid=397ae248195d7499e90a61fda12a2641

he would like me to build him a splitter to run his Roland VK7 into the rhodes amp, with two independent volume controls for each keyboard.  I looked around to see what each pin does, and this is what i found:

    * 1 = +25V DC (red)
    * 2 = Channel 1 preamp output (green or clear)
    * 3 = Channel 2 preamp output (green or clear)
    * 4 = Ground (black)

would this be fairly simple, or difficult to pull off?  what would be the best way, if it is doable?

thanks guys!

[theehman]

Wouldn't be difficult at all.  Just build a box that the cable from the Rhodes plugs into, make another cable from the amp to the box, and have a couple of switched jacks on the box connected to the signal path that would let the Rhodes thru when not in use but would route the signal of another instrument to the amp when plugged in.
I have a Rhodes 73 I bought at the Salvation Army ($20) that didn't come with the amp.  I built a box with a power supply and a couple of jacks so I can power the Rhodes up and plug the output into any amp I want.

[jlullo]

ron,
great!  what size pots should i use?  how i would i connect the 1/4" jack (for the roland) to the 4-pin output jack, since i don't want to A/B, but want to blend.... ?

thanks!

[theehman]

ron,
great!  what size pots should i use?  how i would i connect the 1/4" jack (for the roland) to the 4-pin output jack, since i don't want to A/B, but want to blend.... ?

thanks!

Why does he need a blend function?  Would he ever use both at once?

[jlullo]

yes unfortunately.  is this not possible?

[theehman]

Not impossible, just more complicated.  The simplest way to would be incorporate some kind of transistor or FET mixer circuit to provide good isolation.  You could tap off the Rhodes power supply to power the mixer circuit.