Sometimes you need to get things right and one of these things was to get good music on the terrace. So I did some research and read up on the reviews of external weatherproof loudspeakers and decided to go for Bose speakers, but I hesitated between Bose 151 SE and Bose 251. So, I bought both and connected them to my NAD chromecast amplifier.
However, I thought I was able to get the best decision from the published reviews, but I missed out in those some of the conclusions I made in my own comparison, so I decided to write them up here.
Comparison Bose 151 vs Bose 251
So, both speakers come out very well through different tests and reviews. I will not repeat those, but will add my own observations here.
Size and weight
First of all, I was amazed by its size. They are large and they are similarly sized. If you see the pictures, you may believe the 151 model is much smaller, but the truth is that are very similarly sized and they are big. They are not the carry-on Bluetooth speakers you can just carry with you to a party. No, you need to install them properly, because they are heavy as well, and you do not want them to fall and break up...
You can see from the pictures that they are very similar in shape. The width is the same, but they differ slightly in depth and in height. The depth is thanks to the large woofers the Bose 251 offers and presents a larger sound space. The Bose 151 does not have a separate woofer and hence its more compact size.
Here is a table with differences in specifications:
If you lay them on top of each other, you can really see the difference is very small. I put the 251 below the 151 and see that only the back is a bit deeper thanks to the woofer. Also the curve of the Bose 151 is more rounder to distribute its sound in a wider angle.
There is a clear difference in weight, so ensure that the wall or wood is strong enough to support them.
Installation
The installation of these speakers is another difference. The Bose 151 come with a special plastic bracket that allows the speakers to position them up and down. The Bose 251 come with a metal bracket that allows the same alignment. Both only offer up and down alignment, but no horizonal alignment.
I hanged them up in my outside space on the ceiling without little effort. Note that in both speakers you can rotate the "Bose" label so it does not look like that the speakers are hanged up incorrectly.
The Bose 251 installation is also quite easy, however, as they are heavier, you need to ensure that you place them solidly on the wall or wood. Note that the 251 can only be positioned vertically where the Bose 151 can be positioned horizontally and vertically. However, the recommendation for the latter is to position them horizontally which I will explain the next section.
In terms of presence, the Bose 151 are a little bit nice to see, they are not that bulky as the 251.
They are both passive speakers and need an amplifier. The Bose 251 are 100 Watt RMS, and Bose 151 offer 50 Watt RMS. They both do perform well on my NAD Chromecast C338 amplifier that provides 50-100 Watt RMS power.
The speaker cable can be connected through direct wire screwed-in or use of banana plugs. You can use both at the same time as well to connect speakers in parallel. However, connecting the Bose 251 and 151 in parallel is not very good as the 151 has some sound quality issues where it ends up providing some digital hissing sounds. I believe that is because the 151 varies in impedance depends on its frequency and therefore affects the overall impedance in case of mounted in parallel. It was easier to install a RCA splitter and 2 cables to 2 amplifiers, one for each pair of speakers.
Position and Sweetspot
Here is the more important thing to me and that is about which speaker performs better. I positioned them in various locations on my terrace and even though you might expect slight differences, I believe they do differ significantly to make a balanced decision.
The first thing is its sweetspot of the sound. When I position the speakers I walk around the speakers and try to listen where I can hear clearly the sound and voices played and where it starts to rumble.
The difference has to do with how the 151 and 251 are built. The Bose 151 has 3 speakers located in its front. Its 3 speakers are positioned in a half circle trying to cover a wider area. And that is definitely what I hear. The Bose 251 only has 2 speakers located with an angle, but do not cover the wider angle the Bose 151 offer.
Another difference is the clarity of the sound. I must say I do have to say when standing a bit further from the speakers that the Bose 251 wins. Its sound makes me feel I am sitting live with the singer, while with the 151, even though the difference is small, it does not penetrate with the same crispiness that far. But again, the angle of the 251 is narrower, so as soon as you leave the speaker sweetspot, the 151 is the better one as it reaches wider plane.
It also differs in distance and fullness of its sound. I noticed that the 251 carries the sound better over longer distance, where the 151 covers shorter distance. If you walk away of the 151, the sound does not carry that far as I it lacks the woofer. The bass of the 251 is a little light that I noted in a studio compared to high quality indoor speakers, but in outside environment is very good.
Conclusion
So, what I have now is a Bose 251 and Bose 151 in my terrace and pool. They are both top quality speakers. Due to its different characteristics, I placed them in different locations. The Bose 151 serves well smaller outdoor spaces such as the dining and cooking space, but to me the Bose 251 is the winner on its nicer sound quality and larger distance it can cover. I use the 251 for larger deeper areas such as the open terrace and swimming pool as it covers with more warmth the music I want to listen.