Ambika SMR4 Voicecard BOM Verification

Hello all

I’ve just finished my Ambika SMR4 filter board BOM and wanted to confirm the following two substitutions:

C1, C21:


(The BOM specifies the latter, but the voltage is 25 V compared to the required 35 V)



(The yellow LED specified in the BOM is on backorder)

Here is the whole project minus AtMega328p:

So you want to use this for the c1&c21 then?
Should be ok, be aware that the 50v version probably is (significantly?) larger than the 25v version…

The BOM specifies V > 35 V, which led me to seeking out the bigger caps. This cap is 1.3 mm wider and 4 mm shorter than the 25 V version, which doesnt seem like a huge difference, but the board is pretty tight so I will have to measure.

Resurrecting this thread - I went by the Mouser BOM that is listed on the wiki , and I ordered these because of it.

But now I note, as above, that the Mutable Instruments BOM suggests that the caps need to be >35V. So am I screwed, and need to re-order the 50V suggested above? @dtforgette, did they fit?

Usually that shouldn’t be a problem, although C1 sits directly behind an amp, so I can’t say for sure. But I believe most people ordered after that list at Mouser and I didn’t see anyone having a problem with their cap. If you take a look at the MI BOM, it lists those exact 25V caps aswell.

i think the highest voltage present in the ambika should be 18V from + to - so you’re definitely fine with 35V rating.

Thank you guys. Yeah I didn’t realize that the same part is listed on the MI BOM. Cool. Thanks again.

@Olivier, you may want to make a notation on the MI BOM for the future, to avoid confusion where people like me and dtforgette question whether the 25V cap from Mouser is sufficient?