some 2015 grid users have reported a high pitched noise coming from the grid when lots (and lots) of LEDs are lit up. i’ve identified the problem and a simple fix-- the problem is that in these new builds, the type of capacitor was incorrect. two ceramic capacitors were placed by the boardhouse instead of tantalum. we didn’t catch this error during inspection as the grids function perfectly well-- but for the sake of making these grids more perfect, here’s what needs to be done to reduce the potential for high frequency noise:
obtain 10u and 4.7u 1206 sized tantalum capacitors. e-mail firstname.lastname@example.org with your address and we can send you one of each. if you’re really in a hurry (particularly if you’re not in the US), part numbers are T491A106K010AT and T491A475K016AT (you can use similarly rated parts, of course).
remove the two bottom screws of the grid using a 1/16" hex key.
the capacitors are now visible, see diagram below:
desolder both capacitors. there are a variety of ways to do this, but the easiest perhaps is to add extra solder to both sides, then alternate touching the iron to each side until both are melted, where you can then flick the capacitor aside.
remove the remaining solder with solder wick or by another method of your choice.
solder on the new tantalum capacitors, respecting the correct orientation (make sure the line on the PCB is the same as the line on the capacitor itself. see image below.)
if you don’t have a soldering iron or are uncomfortable doing this mod, contact email@example.com with your mailing address. we can discuss some options.
lastly-- if you haven’t had an issue with your grid, please don’t feel like this is an obligatory mod. there’s no functional issue with the device and the life of the hardware is by no means compromised.
all grids shipping from us in the future will have this issue corrected. all grids currently stocked at retailers will have the old ceramic capacitors. this is not a big enough deal to merit any sort of recall.
my kit is affected, but the noise is barely noticeable even when you listen closely. still thanks for the fixing instructions, @tehn. i’m gonna do that just for the sake of fun you get when hacking the monome
Yes my kit is affected too, doesn’t bother me much, but is a really easy fix so i’ll do it at some point thx!!! if someone is in Madrid or Berlin and is not comfortable fixing this send me a line and i’ll help
hey, not sure if I have this problem or something else. I have a Grid I bought from Control about 3 weeks ago plugged into my White Whale. When it’s plugged in I hear a high pitched sound like at around 8K. If I press the memory button on the White Whale the sound stops. I was thinking it was a ground loop or something, but maybe it’s what you are describing here.
Just made the fix myself, it was not the cleanest work as I am totally inexperienced in soldering but everything seems to work fine. The difference is absolutely drastic concerning the noise (I have always been sensitive to high frequencies). It is finally a pleasure to control my modular with the grid. Anyway thanks for the perfect assistance.
It’s a good thing you sent the caps taped to a card marked with the capacitance values, because the (nearly invisible) markings on the caps themselves don’t appear to correspond to the capacitance values.
I’m pretty new to SMD soldering. For my edification, if I needed to identify a loose capacitor’s capacitance value, how might I interpret the values printed on the component?
I have a friend ready to make this upgrade for me. Should I expect it to enable me to use White Whale without the Switch module? At the moment I’ve been having the LED-intensity-related noise issue from WW (output is MN Rosie), but I’m not totally clear from the thread whether this grid mod will fix it.
this is an issue with physical noise coming from the grid-- the capacitors vibrate. this should also lessen electrical noise, but modular power supplies and ground design are so different that i can’t assure it’ll be a complete fix. switch provides complete isolation.