Yes a Play:5 is a louder speaker than a Playbar. The names of Sonos products may not be very indicative of their capabilities, and the Playbar is slightly more expensive than a Play:5. This leads many people to think that a Playbar is a more powerful speaker. In some ways, it is, but the Play:5 wins when it comes to pure loudness and quality of sound. This does not mean that a Play:5 is a better speaker though.
The reason that a Play:5 is louder, is because it is a better speaker system, from a pure quality of sound perspective. That is not to say that a Playbar is not also an extremely high quality speaker, but a Playbar is meant for a home theater system and a Play:5 is not specifically meant for that purpose.
Playbar is For Home Theater
A Playbar is a home theater speaker through and through. It is meant to simulate actual surround sound (or augment a full surround sound system). Any soundbar (which is what this device is) has a right, left, and center sound component. So if, for instance, an audio output is Dolby Digital, when the audio is meant to be heard from the right side speaker (as coded by the output) a soundbar will play sound from its right side and will give the impression of surround sound.
A Playbar gets plenty loud for home theater, but at the end of the day it is limited by its narrow size. In reality the sound is excellent but it tends to have a little bit higher frequency because each one of the nine individual speakers are small in diameter. Where the Playbar, and any soundbar, may fall a little bit short is in the creating lower bass tones like those handled by a subwoofer. A Sonos Sub can easily be added to a Playbar and you may consider the sound to be superior at that point to the Play:5.
Play:5- Top Quality Sound
The purpose of a Play:5, on the other hand, is for creating the absolute clearest, loudest, and best tones for music. It can also be used as one component of a surround sound system.
The Play:5 has larger speakers within the self contained enclosure, and this lets it handle low tones better than the Playbar. While there are fewer total speakers in the Play:5 (6 compared to 9), the bass is overall better.
In both systems each speaker has its own driver and amplifier, so you know you can count on the consistent and precise sound that Sonos is really renown for.
Both Systems are Top Notch
At the end of the day either system can be considered the “best” based on the application. The Play:5 gets slightly louder, but a Playbar is far superior for home theater and emulating surround sound.
In many complete home theater systems, people will have both systems hooked up at the same time. The bottom line is either system can get loud enough to blow your ears off, and you probably would never use either at its full volume capacity. Your neighbors may not like you, but you won’t be able to help turning up any Sonos speaker a little.