The little Sonos bluetooth speakers do something like this. I went in search of a teardown to figure out how on earth they get any sort of bass response from that size enclosure, and the innards turn out to be kinda boring. The trick is almost entirely from shoving the real-time room response through software correction. If that could be packaged up for Linux laptops, it would be amazing.

Also, even the best speakers in the world can benefit from room correction, because every room behaves differently. The difference is HUGE in the lower frequencies.

Thanks for the links! I'd been searching (futilely!) for that HN post, I knew I'd seen it and wanted to use it for my framework too.

If you haven't watched the video btw, I highly recommend it. It's quite amazing how much difference a bit of software can have.

> Even with very suboptimal measurement equipment (cheap microphone, questionable audio interface), we can clearly see the sloped bass response

I've always wondered with this, how do you know you're not just measuring the frequency response of your mic?

Modern electret and MEMS microphones are almost flat from 100 Hz to 10 kHz. Here's an example plot:

https://www.allaboutcircuits.com/uploads/articles/CCTB_PUIME...

In contrast, small speakers, especially non-round speakers with plastic diaphragms that are commonly found in laptops, have pretty wild response curves, something like this:

https://www.bestartech.com/wp-content/uploads/2020/09/FRC-BL...

I am skeptical about measurements done using the laptop's microphone, though. These microphone arrays are often designed to be very directional, some laptops have bottom-firing speakers, etc.

For most cheap computer speakers and headphones, you can make them sound better for music and gaming simply by boosting low and high frequencies. And for speech, you often want the opposite...

> I am skeptical about measurements done using the laptop's microphone, though.

While any microphone might be able to provide some ballpark info which corrections to start with, laptop mics will be especially poor. Laptop manufacturers consider conferencing the primary use case for mics so they're intentionally placed and oriented to minimize hearing the laptop's speakers. More recent laptops feature far-field mic arrays which often apply DSP processing in hardware such as equalization, acoustic echo cancellation, spatial beamforming and dynamic multi-band compression with little or no control provided at the OS or app level.

If you care about audio it's worth picking a calibrated measurement microphone. It's one of those tools like a multimeter or colorimeter that are just good to have around. Even ~$100 buys a quite good reference mic you can use with REW to improve output from laptop and PC speakers but also home theater audio. If you have or can borrow one of the calibration mics bundled with Denon Audyssey-equipped AVRs, you can download a community-created REW profile for it. Since it's cheap and analog (3.5mm output), it's not as good as any real measurement mic but if you've got one already, it's better than nothing for measuring relative frequency response. However, if you also want to measure things like absolute dB you'll need to measure the input gain of your sound card's ADC with an SPL meter.

My limited and fuzzy recollection is that while the freq response of most cheap to mid speakers is balls, the freq response of most cheap mics is quite good - sure not studio quality, but much better than the equivalent speaker.

IIRC when using REW you're supposed to feed it the response curve of your mic (which you should get at least as a printout with any good mic) + also do a loopback measurement of your audio input.

Or skip both and assume they're "neutral enough"

Any measurement microphone worth its salt is calibrated (even the cheap UMIK-1) so it comes with a frequency response file or a link to it.