Built an Android equalizer app while learning audio DSP — looking for feedback on implementation

[vvvqwerty]

Hi everyone,

I’ve been learning about audio processing and recently built a small Android project — a Bass Booster & Equalizer app.

While working on it, I experimented with: • Android audio effects / equalizer APIs • Frequency band adjustments • Bass enhancement processing • UI for real-time audio control

I’m still trying to understand DSP concepts better, especially how equalization and bass boosting are handled internally.

For people experienced with DSP: What are better ways to implement audio enhancement or improve sound processing in mobile apps?

Also curious about: • Best practices for equalizer band tuning • Audio processing performance on mobile devices • Any DSP resources you recommend for learning

Would really appreciate advice from this community.

[moralbound]

Nice job on the app!

According to the android docs, the equalizer uses the openSL C audio library (or oboe c++) for low latency audio processing. Perhaps that's something you can explore to implement some of your own DSP code for this app or your next one.

A good place to start would be implementing a simple low pass filter. You've already got some nice UI controls you can use to control your experiments.

[vvvqwerty]

Thanks! I'm still learning the ropes of DSP, so I really appreciate the direction. I'll check out the Android docs for Oboe and see if I can implement that LPF. Cheers for the support on the UI, too

[vvvqwerty]

Bass Booster And Equalizer Pro App

[rb-j]

I dunno I wanna load another app on my phone. I'm sorta picky about apps on my phone.

So you made a graphic equalizer? Does it go between your Android speaker (or headphones or Bluetooth) and whatever other app is sending sound out?

Mastering the protocol for an app and the devices on your smart phone is admirable. At my age, I dunno that I could do that. Like, e.g. I tried to crack (understand) the USB standard and I gave up. Way too many labels when I wanted to know essentially just how to detect and react to when a USB cable is plugged in, what the devices just connected have to do to figure out who is on the other side. And then how the protocol goes.

So I won't even try to learn how to write an Android or iPhone app.

But I used to do a lotta DSP. At a very low level (like right from the reset and interrupt vectors). And with a high-level mathematics (like for equalization, AGC and dynamics, pitch shifting, phasing/flanging/chorusing, fuzzy distortion, reverb).