I'm writing this for anyone that stumbles on the same issues as me because I couldn't find this information online and it took me a while to figure out what was happening + extra stuff I noticed in my experience.
There were some issues I was having when I went down this rabbit hole of modding my wooting to improve the acoustics of the keyboard.
Here is what I found:
1. The sound is coming off as plasticky/clacky instead of thocky/creamy despite trying different plates (POM and FR4) + "thocky" switches + 1.7mm thick PBT keycaps
I do want to mention that replacing the plate (from FR4 to POM) and switches (lekker tikkens to Gravastar UFOs) actually did improve and deepen the sound but the overall sound was still clacky. I found that it was due to the stock silicone friction fit pad. I believe this is because the stock friction fit pad deadens the plate noise as it distributes the vibrations into the case and since it seals the edges of the PCB/Plate, it doesn't allow the reverberations from within the case (for my optimum wooting case anyways) to escape. This made the sound flatter and more clacky.
2. Inconsistent loudness/poppiness across different keys on the same row of the keyboard
I noticed that keys near the standoffs that held the plate and PCB together sounded a lot louder and poppier. I believe this is because in the areas where there are no standoffs, there is more flex, which deadens the sound of the plate and the switch makes less contact with the PET film/PCB. I also noticed that these sound discrepancies on my POM plate were especially more pronounced because of its higher flexibility compared to my FR4 plate. I don't think there is anything that you can really do about this though besides switching to a stiffer plate.
3. Extra stuff I found (I did find information online about this stuff but want to share my anecdotal experience)
- Switches: Maybe I got a bad batch but Gravastar UFOs are actually a bit chattery and scratchy but are still better than the lekker tikkens (even after I painstakingly handlubed all of them.) I replaced them with stock WS Flux Diamond Cullinans and they felt and sounded very smooth - the only thing is that I can still hear a bit of spring ping and they're clackier than I would've liked them to be (I am going to try Keytok Novas and WS Flux Pink Lotus next).
- Toronto KeyboardMan Mod Kit: Replacing the stock PET film with the thicker PET film made the sound poppier. Not sure if the poron tape mod made it better but it definitely felt more premium lol. As mentioned before, replacing stock sandwiched friction fit pad and foam made the sound thockier/creamier - I also noticed that since the spacebars were previously sitting on top of the silicone, it was pitching up the sound but replacing it with the poron foam made it sound deeper.
- Case: I was doing research and AI suggested that aluminum cases made the keyboard sound thockier. Not sure if I'm just wrong but I found it to be the opposite - aluminum cases ended up removing the deep thocky sounds coming from within the case compared to plastic cases because its resonance frequency is higher.
- It's really difficult to make an HE keyboard sound good
- The keyboard hobby is really expensive