DarkStar Modification

             First the BAD NEWS ; by opening up your Darkstar by Redsound synth module, you are probably voiding the warranty. So if this is important to you, DON'T  DO IT!!!  (or build this into an external metal box with in's & out's)

Also, if you don't feel you can handle this Mod ,on your own or don't understand what I am showing you here, then DON'T DO IT!!! (or beg or pay a Techie type guy to do it for you)  I don't have time to answer questions or make suggestions as I have too many projects of my own. Sorry ,but if you mess it up you are on your own.

>>>>>>Now for the GOOD NEWS ......

By adding two little transformers to the outputs of this device I have changed it from an amusing but thin & sterile sounding digital device  into a Phat sounding analog style MONSTER!! The whole procedure only took about an hour to perform but the  differance is profound! The highs are much smoother ;none of that digital edgyness & the lows are much fuller.The basses are just ....bassier!! All around the Darkstar just gets darker!

I did this Mod to the First Version of the Darkstar. The Latest version has more outputs so I do not know if there is sufficent room to install the transformers inside the unit, like I did on mine.

First thing I did was to open the unit up by removing the 4 screws in the back. There is sticky tape,behind the back cover that will hold it in place,so you could leave it in place. There are also 3 screws on the bottom front corner, these too must be removed,then the top cover swings up, from the front, with all the knobs &

electronics still attached. 

 You have to seperate the PCboard from the top panel so you must first ,pull all the knobs off the front panel. then flip the board over & remove these screws..& unplug the JoyStick connector.I put a mark on the connector & the board ,with a sharpie, so that I don't reconnect it,backwards.                The screws with the red X's, do not need to be removed. All the others must be removed to free the PCB from the front panel.

When you have the unit open, be gentle with the PCboard as the traces are very fine & can be easily damaged. Now you must cut a trace and add two wires to the top of the board.

              Click on these pictures for a closer look at the right spots to cut the trace & add the two wires. I widened two of the holes on the PCB so I could chase the wires through them. After this is done, I reassembled the PCboard to the front panel.    Now, you have to make two cuts to the output jacks ,these are the two right next to the Midi jacks . Use a good set of side cutters or a Dremal tool with a metal cutting disk but be CARFUL! Be sure that you don't nick the PCB or twist the solder joints with your cutters. Once these cuts are made, you must carefully bend those metal tabs away from each other, so wires can be soldered to them.

Time to talk about transformers. You need a pair of matching transformers, because ,this is a stereo modification and you want both outputs to sound the same. I used the 2000ohm secondary as the input and the 600ohm primary as the output. Basically, any 3 to 1 audio transformer will work but there are a few guide lines.

1. The frequency response should be, at least 50 htz to 20khtz.

2. The power level should be in the 10 millawatt range ,go too low and the transformer over saturates and distorts ,go too high and it will sound too clean and defeat the purpose of  doing this mod in the first place.

3. It should be small enough to fit inside your DarkStar or inside any metal enclosure that you want to build it into.

What ever transformers you use, make sure to test them first,BEFORE you open your unit up!  You can use jumpers & a cutup RCA cable to patch it into the output of one channel, that way you can A,B it, or compare it to the other channel ,to hear if you are getting the desired effect. You may lose some signal on the effected channel but if you lose a lot ,play with the different taps on your transformer intill you get what you want. Also pay special attention to phase. What that means is that you can invert the phase of a signal through a transformer if you are not paying attention. You can check it with a scope or use your ears, if it sounds kinda strange then try swapping the taps on one side of the transformer. 

Well, now it's time to wire up the transformers. Both input grounds to the transformers hook up to the PCboard ground ( the black wire coming thru the PC board,on my unit) & both output grounds from the transformers tie to the Jack grounds ( the white wire chasing thru the PCboard on my unit). Then the input of each transformer solders to the PCB side of the cut you made in the output jacks. The output of each transformer solders to the Output Jack side of those jacks. Click on the proceeding pictures for a closer look or the little diagram I drew up. 

After all the wiring is done, I affixed the transformers to the bottom plate with double sided tape. You might want to use screws or hot glue on yours if you are gonna' take it out of the house, but mine stays in the studio, so tape is fine. Then the rest of the housing is reassembled, and now ,my DarkStar has a whole new attitude! 

If all this is too much trouble for you ,just put the whole thing in a metal box with RCA input jacks & maybe 1/4 output jacks. You could even balance the outputs, with the right transformers, but i'll leave that up to you.

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