Name: Panasonic RZ-S 300W
Brand: Stereo Guide

STEREO GUIDE Verdict

85%

85%

+ clarity, fine resolution and natural balance
+ small, light and good battery life
+ app works smoothly
+ trouble-free phone calls as long as the environment is not too loud
- for balanced sound, you have to make some EQ settings
- dynamic range is limited

Sound: Tonal Balance / Transparency
9
Sound: Bass / Dynamics
7.8
Ease-of-use / Connectivity
8
Price/Performance
9.3

The Panasonic RZ-S300W is a true wireless earbud and looks like a little brother to the RZ-S500W. As the only sacrifice on the spec sheet, it comes without any active noise cancelling technology. Nevertheless it is meant to attract those frequent travellers not being annoyed by low-frequency airplane noise (because they rather take a train). So the list of advantages one gets in return is significant: smaller case, less weight, and significantly longer battery life. Apart from offering not the same number of built-in microphones and lacking ANC, both models are by features almost identical. This said, the earbuds offer a voice-through mode for announcements that can be activated on at the touch of a button. As a bonus, there are quite useful features such as voice control with Siri, Alexa and Google Assistant if your smartphone is offering such.

Functions and features

The Panasonics are connected via Bluetooth (5.0) with the codecs AAC and SBC, controlling quite a lot of basic functions for music playback and phonecall handling at the touch of a finger. Other settings such as the 5-band graphic equalizer are enabled by Panasonic’s own app. Since the left and right earpieces establish a separate Bluetooth connection, one can expect a pretty stable connection in everyday use.

Exemplary connectivity with the Panasonic RZ-S300W

The Panasonics are very light with 4 grams each and hold very well thanks to five different sizes of rubber adapters and their small diameter. They sit excellently and were found to be comfortable by all test subjects. Sealing the ear canal was not a problem in any case. When one is moving his/her head instantly, for example during rough sport activity, the plugs can of course fall out, but they give a really secure feeling.

The manufacturer promises up to 7.5 hours of operation without recharging. After that period, one can insert them into the rounded, flat plastic case, which ensures to recharge the buds three more times. Thus, up to 30 hours are theoretically possible, in field testing we found it to be a very good 25.

To connect via Bluetooth, both Ear Buds must be set to pairing mode. For this it is necessary to consult the quick start guide once, as it is not self-explanatory. Since establishing the connection and pairing with Panasonic´s app work absolutely smoothly and the finger touch sequence is quite memorable, the manual is obsolete afterwards in most of cases. In general, the connection stability, operation and range of functions are exemplary, and the Panasonics did not show any weakness in the test. At most, there were suboptimal results in terms of voice quality when making calls in noisy environments. However, it is not possible to connect multiple smart devices; the connection must always be completely disconnected before a new smartphone or tablet can be connected.

Sound and passive noise isolation

The small Panasonic RZ-S300W sit very comfortably in the ear and give the listener the feeling of “passive noise isolation” even without music. One feels acoustically pleased and decoupled from the environment. At most, very low-frequency noise is let through quite noticeably, for example in an airplane. The voice-through function called “transparency mode”, which is sometimes activated by default when connecting via Bluetooth, is noisy and shows somewhat annoying echoes, so it should first be deactivated when listening to music. However, it is really useful to listen to announcements on planes, trains and stations with sufficient clarity.

With music, the Panasonic RZ-S300W initially showed a subtle and dynamic performance that was even convincing to audiophile ears. At most, the tight, somewhat restrained bass and an equally thin tonal fundament gave the impression of somewhat bright timbre. However, one must attest to the fact that they played excellently dynamically and were never annoying. If you prefer more balanced or warmer overall voicing, you can use the equalizer in the app to quickly and accurately adjust the affected frequency bands to your own preferences. A moderate boost of bass and fundamental as well as a cutback of the two treble registers do the job in a minute.

Bass boost available

Strong effect in the low frequency range can also be boosted by activating a special bass emphasis separate from the EQ. In return, the bass is also somewhat bloated in this mode. The Panasonics basically deliver astonishing SPL and offer very good subjective timing. On the other hand, nothing feels exhausting or too loud when playing material recorded with a high dynamic headroom, something from jazz and classical. Quiet pianissimo passages can sometimes “drown” a bit. Too bad, a slightly higher gain would have resulted in substantially more dynamics here. The source should definitely allow full output level via Bluetooth.

For most music genres, however, the Panasonics deliver a very convincing performance with appropriate EQ adjustment.

Conclusion and alternatives to the Panasonic RZ-S300W

If you can do without noise-cancelling and are willing to adjust the EQ, the Panasonic RZ-S300W is one of the best-sounding true wireless in-ears if you are not expecting to listen to highly dynamic classical recordings in a plane.