In this review, we will be comparing LS50 Wireless II and Navis ARB-51, two Powered Bookshelf speakers from KEF and ELAC. Being Powered speakers, they both have built-in amplifiers so you don't need an external power amp or an integrated amp to power them.
Let's have a brief look at the main features
of KEF LS50 Wireless II and ELAC Navis ARB-51 first before getting into our more
detailed comparison.
| Key Specs | KEF LS50 Wireless II | ELAC Navis ARB-51 |
|---|
| Brand | KEF
United Kingdom · founded 1961 | ELAC
Germany · founded 1926 |
|---|
| Design | 2-way | 3-way |
|---|
| Built-in amplifier | 380-watt RMS (760-watt peak) | 300-watt RMS (600-watt peak) |
|---|
| Uni-Q driver | 12th Generation Uni-Q | — |
|---|
| Tweeter | 1" Hard-Dome | 1" Soft-Dome |
|---|
| Midrange | — | 4" |
|---|
| Woofer | 5.25" | 5.25" Aluminum |
|---|
| Frequency response | 45-28k Hz | 44-28k Hz |
|---|
| Max depth / sample rate | Yes / 384 kHz | — |
|---|
| Bluetooth | Built-in | Optional |
|---|
| App control | Yes | — |
|---|
| Weight | 20.10kg / 44.2lbs | 8.10kg / 17.8lbs |
|---|
| Dimensions (H x W x D) | 10.9375" x 7.875" x 12.6875"
277.8 x 200.0 x 322.3mm | 13.8125" x 7.5625" x 11.3125"
350.8 x 192.1 x 287.3mm |
|---|
The sections below take each area in turn: drivers, frequency response, physical size and what you get in the box.
Drivers
One of the fundamental differences between these two speakers is that LS50 Wireless II is a 2-way design whereas the Navis ARB-51 is a 3-way speaker. 3-way designs utilize a midrange driver in addition to the tweeter and woofer on 2-way designs. Designing a crossover for a 3-way speaker is a complicated process and generally increases the overall cost of the speaker.
KEF LS50 Wireless IIELAC Navis ARB-51
TweeterMidrangeWoofer
Front view, drawn to scale - cabinets and drivers share one scale, so sizes are directly comparable. Hover a driver for its size.
| Driver |
KEF LS50 Wireless II |
ELAC Navis ARB-51 |
|
Driver Setup
|
2-way
|
3-way
|
|
Tweeter
|
1-inch
|
1-inch
|
|
Midrange
|
- |
1 x 4-inch |
|
Woofer
|
1 x 5.25-inch
|
1 x 5.25-inch
|
LS50 Wireless II features a 1" Aluminum Hard-Dome Tweeter and 1 x 5.25" Woofer. On the other hand, the Navis ARB-51 features a 1" Fabric Soft-Dome Tweeter, a 4" Midrange and 1 x 5.25" Aluminum Woofer.
Frequency Response
LS50 Wireless II has a frequency range of 45-28k Hz whereas Navis ARB-51 has a frequency range of 44-28k Hz. With a minimum frequency of 44Hz, the Navis ARB-51 can go slightly deeper then the LS50 Wireless II's min frequency of 45Hz.
The graph below depicts how these two speakers compare with the max, min and average Low Frequency values of other speakers in the Bookshelf class in our database.
Low Frequency
Bookshelf Speakers
Neither pair reaches down to 20Hz, the usual definition of full-range, which is normal for speakers of this size. If you want the bottom octave for movies or bass-heavy music, add a subwoofer to whichever you choose. Visit our Powered Subwoofers section to find out more about the available options.
Cabinet Type and Port Position
Both LS50 Wireless II and Navis ARB-51 have rear firing ports. Rear ported speakers generally need more room between the backside of the speaker and the wall compared to sealed and front/bottom ported speakers. Placing the speakers too close to the walls may cause the bass to sound boomy.
If you are limited in space and can't get the speakers away from the backwall, check our Speakers with Front Firing Ports page.
Physical Specs
The size of a speaker can sometimes be an important decision factor due to space constraints or in some cases purely for esthetic reasons. In this section, we are going to compare KEF LS50 Wireless II's and ELAC Navis ARB-51's external dimensions. KEF LS50 Wireless II has external dimensions of 277.8 x 200.0 x 322.3mm (10.9375 x 7.875 x 12.6875inch) whereas ELAC Navis ARB-51 has external dimensions of 350.8 x 192.1 x 287.3mm (13.8125 x 7.5625 x 11.3125inch).
ELAC Navis ARB-51 is 7.9mm narrower and 35mm less deeper than KEF LS50 Wireless II but it is also 73mm taller.
Below you can see the front view size comparison of KEF LS50 Wireless II and ELAC Navis ARB-51 in scale.
Comparison image of KEF LS50 Wireless II and ELAC Navis ARB-51 Size and External Dimensions
Base Surface Area Comparison
Base surface area of a loudspeaker may become a determining factor when the space in your room or desk is limited.
The base surface area of the KEF LS50 Wireless II is approximately 644.6cm2 / 99.9inch2 and base area of the ELAC Navis ARB-51 is approximately 551.9cm2 / 85.5inch2. The LS50 Wireless II requires 17% more surface area than the Navis ARB-51 which gives it a small disadvantage on placement in tight spaces.
Here is another comparison that shows both speakers on a BDI Octave Media Cabinet, next to a standard size amplifier and turntable in scale:
Size Comparison image of KEF LS50 Wireless II and ELAC Navis ARB-51 on a Media Console
Weight Comparison The weight of a loudspeaker can become an important factor if you need to move and reposition the unit often. Weight of a speaker can also "sometimes" be an indicator of the rigidity of the enclosure and the quality of the internal components used. The KEF LS50 Wireless II weighs 20.10kg / 44.2lbs and the ELAC Navis ARB-51 weighs 8.10kg / 17.8lbs. This makes the LS50 Wireless II 148% heavier than the Navis ARB-51.
Here is a comparison of how LS50 Wireless II and Navis ARB-51's weights compare with the average, max and min weights in Powered Bookshelf class.
Weight
All Bookshelf Speakers
What's in the Box of KEF LS50 Wireless II?
Here are the items that are included inside the box of LS50 Wireless II:
- 2 Wireless powered speakers
- Two 6.5' AC power cords
- 10' Cat-6 interconnect speaker cable
- Remote control
- 2 \"AAA\" batteries
- Quick Start Guide
- Important Safety Information
- Warranty Information
What's in the Box of ELAC Navis ARB-51?
Here are the items that come with the Navis ARB-51:
- 2 Powered bookshelf loudspeakers
- Two 8-feet AC power cords
- Operating Instructions
 Handheld Remote |
Yes
vs
No
|
Control the speaker by the included RC |
 App-Based Control |
Apple iOS, Android
vs
None
|
Control the speaker via an app |
 Height |
277mm
vs
350mm
|
Easier to fit in smaller spaces |
 Ethernet Connection |
Yes
vs
No
|
High quality streaming over Ethernet |
 USB Port |
Service only
vs
No
|
USB port adds flexibility |
 3.5mm Connection |
Yes
vs
No
|
Connection via 3.5mm AUX input |
 Digital Input |
1
vs
No
|
Connect digital inputs directly |
 HDMI Input |
eARC
vs
No
|
Connect HDMI sources directly |
 Subwoofer Output |
mono-RCA
vs
No
|
Pair your speakers with external subwoofer |
 Driver Setup |
3-way
vs
2-way
|
Have a dedicated mid-range driver |
 Low Frequency Response |
44 Hz
vs
45 Hz
|
Generates deeper bass |
 Base Surface Area |
551cm2
vs
644cm2
|
Takes less floor space |
 Price per pair* |
1998USD
vs
2999USD
|
costs less (*prices may change depending on the seller, location and time) |
 RCA Connection |
Yes
vs
No
|
Connection via RCA input |
 XLR Connection |
Yes
vs
No
|
Connection via XLR input |
| General |
KEF LS50 Wireless II |
ELAC Navis ARB-51 |
| Brand |
KEF |
ELAC |
| Speaker Type |
Powered Stereo Speakers |
Powered Stereo Speakers |
| Frequency Response |
45-28k Hz |
44-28k Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
380-watt RMS |
300-watt RMS |
| Watts Peak (Max) |
760-watt RMS |
600-watt RMS |
| Max Bit Depth |
Yes |
n/a |
| Max Sample Rate |
384 kHz |
n/a |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
5.25" |
5.25" |
| Woofer Composition |
|
Aluminum |
| Tweeter Size |
1" |
1" |
| Tweeter Type |
Hard-Dome |
Soft-Dome |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
4" |
| Firing Direction |
rear |
rear |
Physical Specs |
|
|
| Height |
277.8mm (10.9") |
350.8mm (13.8") |
| Width |
200.0mm (7.9") |
192.1mm (7.6") |
| Depth |
322.3mm (12.7") |
287.3mm (11.3") |
| Weight |
20.10kg (44.2lbs) |
8.10kg (17.8lbs) |
| Enclosure |
Bass Reflex |
Bass Reflex |
| Mounting Bracket |
|
No |
| Moisture Resistancy |
No |
No |
Connections |
|
|
| Aux Inputs |
3.5mm |
XLR, RCA |
| USB Port |
Service only |
No |
| Phone Input |
No |
No |
| Subwoofer Output |
mono-RCA |
No |
| Digital Input |
1 |
No |
| HDMI Input |
eARC |
No |
| Headphone Jack |
No |
No |
| Ethernet Port |
Yes |
No |
Other |
|
|
| Parts Warranty |
3 Year w/ registration |
3 Years |
| Labor Warranty |
3 Year w/ registration |
3 Years |
No single best speaker here - they are built to different priorities, and the right one depends on your room, your sources and what you listen to.
| Area | Better | Why |
|---|
| Bass | evenly matched | Much the same reach (45Hz vs 44Hz). |
| Built-in power | A | KEF LS50 Wireless II has the bigger amplifier (380W vs 300W RMS). |
| Connections | A | KEF LS50 Wireless II adds Wi-Fi, streaming, HDMI and digital inputs. |
| Size | depends | Similar cabinet size - neither is easier to fit. |
| Expandability | A | KEF LS50 Wireless II: a sub output. KEF LS50 Wireless II sits in a wider range (10 models), so a matched surround system is easier later. |
| Price | B | ELAC Navis ARB-51 is cheaper - $1,998 against $2,999, about 33% less. |
A KEF LS50 Wireless II B ELAC Navis ARB-51
depends neither is better in the abstract - it turns on your room, your system or how you will use them. Only specs published for both speakers are judged; anything missing on either side is left out rather than guessed.
Which should you choose?
The usual trade-off: KEF LS50 Wireless II measures better, ELAC Navis ARB-51 costs about about 50% more% less. Whether that gap is worth the money is the call only you can make - and in a normal room it is often smaller than the numbers suggest. Think about the whole system, not just the speakers: the roughly $1,001 saved by taking the cheaper pair would buy a subwoofer or a better amplifier, and either usually does more for the sound than the difference between these two.
And remember what a spec sheet cannot show: how each looks in your room and whether the finish suits it, what dealer support and warranty are like where you live, and how they actually sound to you. If you can hear them first - ideally with your own music - that will tell you more than any number above.