Reviewed on: SoundStage! Solo, November 2022

I measured the QC Earbuds IIs using laboratory-grade equipment: a GRAS Model 43AG ear/cheek simulator with KB5000/KB5001 simulated pinnae, and an Audiomatica Clio 12 QC audio analyzer. I used a Reiyin WT-HD06 Bluetooth transmitter to get signals into the earphones. I used the supplied medium silicone tips for all measurements because they fit best in the ear simulator. These are “flat” measurements; no diffuse-field or free-field compensation curve was employed. Note that I’m unable to do spectral-decay measurements on most true wireless earphones due to the latency. If you’d like to learn more about what our measurements mean, click here.

Unfortunately, something about these earphones and their ability to interface with my measurements gear gave me a great deal of trouble getting usable measurements with my usual techniques. I ended up getting latency that was too high for the Clio analyzer to deal with. So I had to do response measurements using pink noise with a real-time analyzer. This results in measurements that look different from what I usually present, and fewer measurements than I usually present. However, I did not notice any operational or latency problems when listening to the earphones.

Frequency response

This chart shows the frequency response of the QC Earbuds IIs versus the Google Pixel Buds Pro earphones and the TinHiFi T3 Plus earphones, a design I like a lot. Sorry, folks, best I can do—I didn’t have a lot of other samples on hand to run this measurement on, and my usual measurements use a different technique that’s not comparable. Anyway, the QC Earbuds IIs’ response looks pretty normal, and, in fact, rather Harman curve-ish.


Here we can see the differences among the QC Earbuds IIs’ noise canceling and transparency modes: ANC at max, Home, and Aware. It’s interesting to see how the Home mode works—it basically seems to turn the QC Earbuds IIs into something like an open-back headphone design.


Here’s how the Bose QC Earbuds IIs’ noise canceling compares to many competitors’ earphones. In most cases, the Earbuds II earphones beat them dramatically—even models that have pretty decent noise canceling. The only earphones that really compete are the Technics EAH-AZ70s, which more or less equal the QC Earbuds IIs’ performance in the bass, but can’t match the performance above 1kHz. Had I not used these earphones on some dog walks and a couple of airplane flights, I’d assume Bose got that result through better acoustical isolation, because all noise-canceling designs I’ve tried before limit the noise canceling to frequencies below about 800Hz, in order to prevent feedback. But I didn’t note an especially tight fit or ear-filling design with these, so I think Bose may have found some way to get noise canceling to work at higher frequencies, perhaps through active feedback cancellation. Regardless, I agree with Geoffrey Morrison that these earphones deliver a combination of noise canceling and isolation that’s dramatically better than I’ve experienced in any competing product.

Bottom line: Wish I could find a way to dig deeper into these technically, but what I see in these limited measurements is pretty impressive.

. . . Brent Butterworth