Hey everyone its been a while since I got started back to fixing my mics. Now that a seasonal holiday is coming up in my country I finally have some leeway to get back into it. Installed Russell Technologies SM02 circuit board from aliexpress into the boya body.
![WhatsApp Image 2024-02-07 at 12.36.13.jpeg WhatsApp Image 2024-02-07 at 12.36.13.jpeg](https://cdn.imagearchive.com/groupdiy/data/attachments/73/73808-86e5f34eb8f3fe9567c2ab0a946d5a71.jpg)
![WhatsApp Image 2024-02-07 at 12.36.14.jpeg WhatsApp Image 2024-02-07 at 12.36.14.jpeg](https://cdn.imagearchive.com/groupdiy/data/attachments/73/73809-27b130440403fc5249da1a0f56927dd4.jpg)
![WhatsApp Image 2024-02-07 at 12.36.14 (2).jpeg WhatsApp Image 2024-02-07 at 12.36.14 (2).jpeg](https://cdn.imagearchive.com/groupdiy/data/attachments/73/73810-350c1f24567113745e30d8b7c06b8dc4.jpg)
![WhatsApp Image 2024-02-07 at 12.36.14 (1).jpeg WhatsApp Image 2024-02-07 at 12.36.14 (1).jpeg](https://cdn.imagearchive.com/groupdiy/data/attachments/73/73811-0dde2adcf92473a4196d3dc5af9aa1ad.jpg)
Some observations about this circuit: it requires a metallic body to act as a shield otherwise it just picks up interference everywhere. Also maybe because of the way I mounted the pcb and soldering the wires (I had to sand the pcb down about 2mm to fit the height of the mic body bracing), it occasionally makes a very subtle high-pitched whine or pop from shaking the cable/body. I have some idea of how I want to secure the pcb better inside the body but any other suggestions are welcome.
Probably the biggest/unexpected improvement to the mic is actually padding the base of the capsule holder and body with some packing foam to damp internal reflections/resonance. Before this the mic always had a little bit of ringy quality to its sound.
I've kind of figured out how to do the polar pattern switching, so now I'm attempting to find a way to mount the pad/cut/polar switches from the old pcb to this new circuit, but I have some questions about the best implementation for the hpf switch
![mod-rtsm02.jpg mod-rtsm02.jpg](https://cdn.imagearchive.com/groupdiy/data/attachments/73/73812-0ad59896110c879e3ca8e7a29733d29c.jpg)
If I understood correctly the more simple/straightforward ways to implement a HPF in a Schoeps style circuit is either a cap right between the capsule & FET gate, or a resistor across the capacitors after the drain; in this context which is a cleaner implementation without compromising the quality of the signal? I'm targeting to HPF somewhere between 70-80hz.
Optional implementation of the pad is a capacitor across the gate and drain of FET. Is it correct?
![WhatsApp Image 2024-02-07 at 12.36.13.jpeg WhatsApp Image 2024-02-07 at 12.36.13.jpeg](https://cdn.imagearchive.com/groupdiy/data/attachments/73/73808-86e5f34eb8f3fe9567c2ab0a946d5a71.jpg)
![WhatsApp Image 2024-02-07 at 12.36.14.jpeg WhatsApp Image 2024-02-07 at 12.36.14.jpeg](https://cdn.imagearchive.com/groupdiy/data/attachments/73/73809-27b130440403fc5249da1a0f56927dd4.jpg)
![WhatsApp Image 2024-02-07 at 12.36.14 (2).jpeg WhatsApp Image 2024-02-07 at 12.36.14 (2).jpeg](https://cdn.imagearchive.com/groupdiy/data/attachments/73/73810-350c1f24567113745e30d8b7c06b8dc4.jpg)
![WhatsApp Image 2024-02-07 at 12.36.14 (1).jpeg WhatsApp Image 2024-02-07 at 12.36.14 (1).jpeg](https://cdn.imagearchive.com/groupdiy/data/attachments/73/73811-0dde2adcf92473a4196d3dc5af9aa1ad.jpg)
Some observations about this circuit: it requires a metallic body to act as a shield otherwise it just picks up interference everywhere. Also maybe because of the way I mounted the pcb and soldering the wires (I had to sand the pcb down about 2mm to fit the height of the mic body bracing), it occasionally makes a very subtle high-pitched whine or pop from shaking the cable/body. I have some idea of how I want to secure the pcb better inside the body but any other suggestions are welcome.
Probably the biggest/unexpected improvement to the mic is actually padding the base of the capsule holder and body with some packing foam to damp internal reflections/resonance. Before this the mic always had a little bit of ringy quality to its sound.
I've kind of figured out how to do the polar pattern switching, so now I'm attempting to find a way to mount the pad/cut/polar switches from the old pcb to this new circuit, but I have some questions about the best implementation for the hpf switch
![mod-rtsm02.jpg mod-rtsm02.jpg](https://cdn.imagearchive.com/groupdiy/data/attachments/73/73812-0ad59896110c879e3ca8e7a29733d29c.jpg)
If I understood correctly the more simple/straightforward ways to implement a HPF in a Schoeps style circuit is either a cap right between the capsule & FET gate, or a resistor across the capacitors after the drain; in this context which is a cleaner implementation without compromising the quality of the signal? I'm targeting to HPF somewhere between 70-80hz.
Optional implementation of the pad is a capacitor across the gate and drain of FET. Is it correct?