User Experience

Seen above is the right ear bud of the Technics AZ70 installed on an artificial ear mold that is similar enough to my own average-sized ears. These are not the most comfortable set of TWS earphones I have used as several smaller and more ergonomically shaped sets compete for that title. The Technics AZ70 earphones are still comfortable enough despite appearances suggesting otherwise. Each earphone also weighs more than the average TWS set at 7 g, but once again not to where it is a deal breaker. The fit is such that the Technics logo is visible for branding, and there is plenty of real estate for all the touch controls. There is minimal support from the concha, with the fit in the ear canal doing the heavy lifting. A good fit is critical thus, and that is also valid for isolation—both passive and active. The ANC implementation is very well done in combination with the vents, so much so that I did not feel any pressure imbalance as with many other ANC TWS earphones.

Battery life is a key metric for TWS earbuds, and these promise 6.5 hours of use when fully charged and in ANC mode, which turned out to be close enough to the truth with even the "better" AAC codec. I routinely got 6 hours of use with volume set to ~70% on my phone, and closer to 9 hours with the ANC and ambient modes off, which is how I mostly used these. The included case provides an additional two charge cycles, so expect 25+ hours as a best-case scenario. This is why I wanted the case do more, especially given its relatively large size. The quick charge function is admittedly nice in an emergency, and a fully charged set (case and earphones) can be enough for a weekend break without worrying about charging these, which in turn would take ~4 hours for both. The IPX4 water resistance also makes the Technics AZ70 a gym buddy, with the ANC feature coming in handy there, too.

Audio Performance

Audio Hardware and Microphones

As is the case with most TWS earphones, Technics uses a single dynamic driver per ear bud, in this case a 10 mm PEEK (polyetheretherketone) diaphragm with a graphene coating for a number of potential benefits depending on the implementation, including a more efficient driver by cutting down the magnetic flux required to move the diaphragm back and forth, which can cut down on unwanted distortion for improved sound quality. Technics boasts a large soundstage courtesy the larger drivers, as well as a smoother, clearer treble response owing to the stronger diaphragm. The acoustic chamber design draws on that of the Technics EAH-TZ700 flagship-class earphones, with the controlled airflow pointed out in particular as far as the frequency response in the lows and mids is concerned. This is more marketing on the sound signature of a TWS set than I usually see, and I am all for it!

The rest of the feature set prioritizes the software and technological functions, including algorithms to make the most of the ANC and ambient mode features, as well as talking about the placement of the Bluetooth antenna and touch sensor for a stable connection and reliable touch controls. The latter I can certainly vouch for since these were definitely the best in that regard with no phantom taps or, more annoyingly, taps and gestures going unnoticed. Everything actually worked as advertised, so I had a really good time using these controls for operating modes, volume control, media playback, and phone calls. Speaking of which, microphone quality is better than average but not the best, especially compared to TWS sets with an extended section pointing towards your mouth and the microphone closer to pick up your voice better. It is still highly respectable for a TWS set, enough to where your typical Zoom call on a laptop will not be held up by the Technics AZ70.

Frequency Measurement and Listening

I will mention that I have a general preference for a warm neutral signature emphasizing a slightly elevated bass and smooth treble range with detailed mids and good tonal separation. I also generally prefer instrumental music over vocals, with favored genres including jazz and classical music.


Our current testing methodology begins with a calibrated IEC711 audio coupler/artificial ear the ear buds can feed into to where there is decent isolation similar to real ears. The audio coupler feeds into a USB sound card, which in turn goes to a laptop that has ARTA and REW running and these TWS earphones connected to the laptop through Bluetooth. I begin with an impulse measurement to test for signal fidelity, calibrate the sound card and channel output, account for floor noise, and finally test the frequency response of each channel separately. Octave smoothing is at the 1/6th setting, which nets a good balance of detail and noise not being identified as useful data. Also, the default tuning was used for testing, and no app-based settings were chosen unless specifically mentioned. Each sample of interest is tested thrice with separate mounts to account for any fit issues, and an average is taken of the three individual measurements for statistical accuracy. I am also using the pinna mold fitted to the audio coupler for a separate test to compare how these fare when installed in an ear and cheek geometry and not just the audio coupler by itself. The raw data is then exported from REW and plotted in OriginPro for an easier comparison.


The IEC711 is such that you can't really compare these results with most other test setups, just within our own library of measurements. The raw dB numbers are also quite contingent on the set volume, gain levels, and sensitivity of the system. What is more useful information is how the left and right channels work across the rated frequency response in the Technics AZ70, or at least the useful part of it. The left earbud was separately tested from the right one, and colored differently for contrast. I did my best to ensure an identical fit for both inside the IEC711 orifice, so note how the two channels are quite consistent and channel matching is quite good, with a +/-1 dB variation at most throughout the entire 20 Hz to 20 kHz range. This is of course considering that the IEC711 isn't all that reliable at higher frequencies, but it's not like I heard anything different with these in my ears, either. Technics talks about an independent left-right signaling system to ensure "proper sound balance between right and left channels," which may well be playing a role here. I will also mention that there was no discernible break-in period or effect, so overall reproducibility and consistency are good since the average response for each channel is also basically the same across the three repeated tests. This continues with the artificial pinna response only having a resonance shift in the treble, and the overall response matching the more ideal fit achieved with the IEC711 coupler. Keep in mind that with TWS earphones, the fit is quite important, as is the connectivity and signal strength from the source itself.

Technics is one of the very few companies that has even bothered to talk about the sound signature instead of just the technology on board, although it's lighter on detail still compared to your typical IEM brands. One thing I will point out right away is that the coupler contributes to the resonance peak at ~8 kHz as it isn't as harsh of an offset in practice as it looks to be in the graph. That said, there remain a few tuning issues that keep it from being an excellent set of TWS earphones. The recessed mids are a matter of preference, although the transition into the upper mids happens so early that vocals go from dark to almost shouty. The in-ear resonance compensation, typically seen at ~3–4 kHz also comes up far too soon, which will be weird if you are not expecting it. So you end up going from recessed mids to shouty upper mids and what comes off as weak and damped where you would otherwise at least want a neutral response with a bump catering to said inner ear resonances. I also mentioned above that things aren't as harsh as it seems at 8 kHz, but it's still pronounced enough for some string instruments to take over what would otherwise be a more balanced instrumental orchestra.

These hold back what is otherwise a pretty respectable tuning in the lows and mids, enough to where it's still going to appeal to many looking for a less-aggressive, more balanced V-shaped tuning. There is good energy in the lows without distortion, with a lift-off at 300 Hz and lower for sub-bass and mid-bass emphasis. Technics is using a larger dynamic driver than usual, with a graphene coating on the PEEK diaphragm, and the bass response is definitely the strong point here. I was impressed by the tightness with house music and the strumming notes with bass guitars in jazz and funk music, even nodding my head along as I occasionally listened to Motörhead when going through my music collection. There is some punch here, although I would not describe it as slammy. The transition to the mids is smooth, but some bleed-over from the bass affects imaging. Male vocals are quite good even if they are certainly not forward-facing. The soundstage is impressive as well, with a better holographic experience than any other tested TWS set to date. Once past the 4 kHz region, the treble response is pretty decent overall, although that aforementioned harsher response comes in again before things roll off past 10 kHz. I now understand why the EQ option in the app ends at 10 kHz—there is nothing but darkness past that point.


Technics advertises battery life and playback with ANC on, so they expect users to have that be their standard operating mode. I have to say that this is one of the better implementations of the same. There is no pressure imbalance and a good deal of active noise cancellation. What I have above is the frequency response of the Technics AZ70 with ANC on; it's not normalized, and I sought to instead show off the compensation applied by Technics to cater to the reduction in the low frequency region with ANC. It's ~6 dB at the highest offset, and this happens in the sub-bass region itself. The rest of the frequency response is otherwise on par with the "off" state to where even with the significant noise reduction of ANC, it's going to sound almost the same as without. This alone makes it worth the price of admission for me, and the Technics AZ70 certainly outperforms the Audio Technica ATH-ANC300TW in both tonality and ANC implementation. The HIFIMAN TWS800 I feel is better tuned and has better technicalities, but is the definitely the lesser of the two technologically while costing more. The EVA2020 x final is another of the more expensive TWS sets I have tried, and I have to say that the Technics AZ70 beats it out, too. In fact, the closest tested competition I can think of is the Lypertek PurePlay Z2 2.0, and it costs a lot less to where the age of the Technics AZ70 may finally be showing.