Over the last two weeks I have had a lot of good progress with regards to finalizing our hardware. After all of the parts arrived last week, I was able to build the first full prototype of the filter and had a lot of issues with it. The sound quality was very poor, with mostly crackling and static at the speaker output. I looked into what issues could cause this, and decided that the most important part to fix were the loose connections. Because I am using a breadboard for prototyping, I did not have the ideal protoboard pin connections to hook up the input jacks that I ordered, and so I had originillay just tried to essentially tie on the wires, but these connections were extremely poor and I feel that was a large reason for the struggle. However, I have now soldered on the wires and made firm connections which hopefully will create a big boost in performance.
Additionally, I realized another obvious issue was that I was building my setup with a single 9V battery with a +Vdd and ground. This is an issue because the opamps require +Vdd and -Vdd, and so obviously this was leading to cutoffs with my audio output. I am now looking into two possible solutions, either using two batteries with the intersection as ground, or creating a virtual ground and splitting the 9V. I am currently leaning towards the former and am hoping to test it out this week. Additionally, I have started building the circuitry for connecting the microphone input into the circuit. There is some worries about how well the ESP32 bluetooth part we are using will work but I have found some examples online about how to use it to build systems like bluetooth speakers and so I am feeling better about the forecast for that.
That will be the first major part of implementation for my work, as the vocal removal is already connected to our webapp.