The EBL's don't have a step up - I think they use maybe 3 internal cells. It has dropping voltage with time so no DC step up. The OK's don't have it and if you can't hear it it is fine to not use CRC filter with the other DC step up. I only added it because I could measured a broad -90dB noise hump from 1k down with the DC switcher step up. 2200uF RCRCRC actually fits in tin with 3000mAHr LiPo and charger an step up.