5 Homebrew Electret & Condenser Microphones

I got a bit obsessed with modding and building microphones. Here are five Frankenstein mic builds I've put together from various microphone donor bodies and capsules. A particular thanks to Jules Ryckebusch (@SoundSleuth) for his excellent Instructables guides which inspired these builds. Mic #1: Schoeps 4 mini electret Body: Maplin "Prosound" dynamic mic Capsules: RS PRO Omni-directional 6mm through-hole electrets (https://uk.rs-online.com/web/p/conden...) Circuit: Schoeps on matrix board Mic #2: Pimped Alice dual large electret Body: BM900 (longer version of BM800 cheap Chinese mic https://www.aliexpress.com/item/32965...) Capsules: Generic 25mm large capsule electrets (https://www.aliexpress.com/item/10050..., or if you want better quality and are in USA or don't mind high shipping fees TSB2555B (https://www.jlielectronics.com/microp...) Circuit: Pimped Alice on matrix board (see guide https://www.instructables.com/Modify-...) Mic #3: 8-capsule electret BM900 mod Body: BM900 (longer version of BM800 cheap Chinese mic https://www.aliexpress.com/item/32965...) Capsules: ---- 4 x Generic 25mm large capsule electrets (https://www.aliexpress.com/item/10050...) x 4 ---- 4 x Generic 16mm electrets (https://www.aliexpress.com/item/10050...) Circuit: Native BM900 with lower noise 5.1V Zener + low pass RC filter on DC rail Grille: Isopon Aluminium Mesh (https://www.amazon.co.uk/UPOL-UPPM1-I...) [You're nuts if you want to build this mic.] Mic #4: LDC Alice full condenser Body: BM900 (longer version of BM800 cheap Chinese mic https://www.aliexpress.com/item/32965...) Capsule: 34mm large diaphragm true condenser (https://www.aliexpress.com/item/10050...) Circuit: LDC Alice on matrix board with inductor-based DC bias generator Mic #5: Body: BM800 (https://www.aliexpress.com/item/32965...) Capsule: 77JC 34mm large diaphragm true condenser (https://www.aliexpress.com/item/10050...) Circuit: OPA Alice + hex inverter DC-DC (see: https://www.instructables.com/True-Co...) ---- PCB #1: Dual OPA Alice in blue (https://www.pcbway.com/project/sharep...) ---- PCB #2: DC-DC Hex Inverter Multiplier in red (https://www.pcbway.com/project/sharep...) ----- Operational amplifier: OPA1642 (https://www.aliexpress.com/item/40004...) I have since built a microphone using a clone U87 body (https://www.aliexpress.com/item/10050..., the Mic #4 34mm true condenser (not the 77JC one), and the two PCBs from Mic #5. The results are outstanding. Very low self noise and excellent sensitivity.