ATM31R mod recommendations

Hello diyAudio,

I just created this account because I am looking for some help with my first mic-mod. I got 4 of this old ATM31R microphones. I really like their look and also the capsule doesn't sound too bad, but they are quite noisy. They work well if I use them with loud sources and for close setups. But in situations where they need more gain the hiss is quite noticeable. So I was wondering if I can get more out of them. I can try to redraw the schematic. I've done some mods before and I am not new to diy. But I am no expert in electronics

Transistors are K223 and C1775. Any recommendations :)? Maybe try some new caps? Or different transformer to get more gain?

Thanks in advance


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