Varthdader´s Shruthi XT build

Hi all

Wanted to share a late night (for me at least) quiet moment of joy as I sit back and enjoy having finally finished my Shruthi-1 XT build.

Everything that could be soldered the wrong way has been soldered the wrong way and re-soldered, including all 4 rainbow cables and switch leds. That would count almost like having built 2 synths!

But it was worth it.

Thanks to Frank for great support!

Hope you all like the retro rainbow knobs.

Victory-candy time!

Like it!
Bullshit in?

Advisory input: the bridge beneath the bridged resistor would be imho a good candidate for shrinking tube. Just to minimize potential trouble here.
Rest is nicely done !

@shiftr: haha it´s a reminder that music should not be taken too seriously IMHO. Hence the in n out vol. pots!

@nightworkxx yes, that area (I guess you mean the switch area?) has been redone since the photo, the leds and filter connections were inverted…leds were cut too short and had to do “microsurgery” with small yellow jumper cables and my trusty tweezers.

Next step is infilling the case´s side panel engravings. Will try the infill-wipe with Isopropyl Alcohol method. Have some Tamiya Modeling acrylic paints from my teenage years that will be brought out of storage for this.

A couple of tips:

-Be careful with the Case´s front and back panels, they´re long, and they are acrylic. I dropped one to the floor and it split in 3 pieces. Not a happy moment.

Superglue and patience stuck the pieces and so far the case has been assembled without problems.
It´s a pity that it was the front panel, and although the seams are not too obvious, I know and hence notice them all the time.

-The shruthi was sitting a bit low in the case, and buttons and encoder were hard to use.

Stuck a nut on top of the hex spacers and then put the digital board on the filter. The Arduino-type headers were long enough to still communicate with the filter, and the buttons, encoder and pots now sat at just the right height. Do this before solrdering leds on the digital control board or they will be to high.

If the Shruthi had an Oled, it would have been possible to have a clear bezel flush with the case´s top. My standard Green on Black lcd is too high, and sits flush with the top face, so I don´t see room for a bezel. Still, I have a sheet of translucent, thin plastic that has given me some ideas that I will try.

As fot the Encoder cutout, I feel it´s too large for the knob design I chose might try to put a black disc underneath the encoder knob to obscure the pcb below.

Nice work. My programmer still has not had the filter switches and modes done so I have some empty holes on the front. As a result my victory candy has gone uneaten.

" My standard Green on Black lcd is too high, and sits flush with the top face, so I don´t see room for a bezel. Still, I have a sheet of translucent, thin plastic that has given me some ideas that I will try."

Bend the tabs on the LCD back as flush as you can, put a piece of tape on the PCB to prevent shorts, and mount the headers on the back side (i.e. the plastic stand off) and you can fit almost any LCD between the front panel and the CS

@altitude: good idea, might try it on my upcoming Polivoks.

In this case, my basic Shruthi was already soldered, and it´s a pain to have to remove all 16 pins of the lcd at the risk of damaging it. Particularly since this lcd is the color I wanted.

Then again, I may just get an oled and have a lower profile if I have to source parts for a future project. Never used one but there seems to be only upsides, with cost as the only downside. And, being brighter, one can put a smoked/darker bezel and it would be ok.

The OLEDs are REALLY noisy electrically, I just had to replace one for a customer as a result. If you want to give the yellows a go, I have 3 to sell cheap ($15+ ship)

@altitude: Didn´t know that thanks for the heads up! How would you go about isolating this noise? I am half-way though the build of a Yellow Magic Shruthi and was about to solder a yellow Oled I have around…

I have’nt been able to put a dent in it. Tried a ferrite, all sorts of caps, nothing really works. Someone recommended a separate Vreg for it

Do really all OLEDs behave equally bad?
I have a green Newhaven OLED in my Yellow Magic and I got some problems with flickering display values etc. A 10uF tantal cap plus a 100nF in parallel on pin 1 and 2 seems to have fixed it.
The red Winstar OLED I put in my Polivoks the other week did not seem to cause these problems though (but I put the caps there anyway after a day or two =) ).

i only have experience with the newhaven parts and all of those show it

@larsen: could you possibly illustrate (photo or drawing) what exactly you did? I am kinda a noob on electronics so it would be great to know what to do if this problem arises.

Another question I have with this issue is wether any of the oled users with issues soldered pins 15 and 16 since they seem to not be necessary and maybe these conduct part of the problem?

I never solder them, AFAIK they are not even connected to anything

How about the trim pot? That is not necessary either right?

Trim pot is not necessary for the OLED…

No jumpers, just leave holes unused?


Are there any backlit LCDs that are especially flat for those who like their display below the panel?