In this review, we will be comparing Prime Wireless Pro and LSX II, two Powered Bookshelf speakers from SVS and KEF. 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 SVS Prime Wireless Pro and KEF LSX II first before getting into our more
detailed comparison.
| Key Specs | SVS Prime Wireless Pro | KEF LSX II |
|---|
| Brand | SVS
United States · founded 1998 | KEF
United Kingdom · founded 1961 |
|---|
| Design | 2-way | 2-way |
|---|
| Built-in amplifier | 200-watt RMS | 200-watt RMS |
|---|
| Uni-Q driver | — | 11th Generation Uni-Q |
|---|
| Tweeter | 1" Dome | 0.75" Hard-Dome |
|---|
| Woofer | 5.25" Polypropylen cone | 4.5" Magnesium/Aluminium alloy |
|---|
| Frequency response | 42-25k Hz | 54-28k Hz |
|---|
| Max depth / sample rate | 24-bit / 192 kHz | 24-bit / 384 kHz |
|---|
| Bluetooth | Built-in 5.0 | Built-in 4.2 |
|---|
| App control | Yes | Yes |
|---|
| Weight | 5.30kg / 11.7lbs | 3.60kg / 7.9lbs |
|---|
| Dimensions (H x W x D) | 11.61" x 7.09" x 8.96"
295 x 180 x 228mm | 9.5" x 6.1" x 7.1"
240 × 155 × 180 mm |
|---|
The sections below take each area in turn: drivers, frequency response, physical size and what you get in the box.
Drivers
Both Prime Wireless Pro and LSX II are 2-way speakers.
SVS Prime Wireless ProKEF LSX II
TweeterWoofer
Front view, drawn to scale - cabinets and drivers share one scale, so sizes are directly comparable. Hover a driver for its size.
| Driver |
SVS Prime Wireless Pro |
KEF LSX II |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1-inch
|
0.75-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
1 x 5.25-inch
|
1 x 4.5-inch
|
Prime Wireless Pro features a 1" aluminum Dome Tweeter and 1 x 5.25" Polypropylen cone Woofer with a Crossover frequency at 2000Hz. On the other hand, the LSX II features a 0.75" Aluminum Hard-Dome Tweeter and 1 x 4.5" Magnesium/Aluminium alloy Woofer.
Frequency Response
Prime Wireless Pro has a frequency range of 42-25k Hz whereas LSX II has a frequency range of 54-28k Hz. With a minimum frequency of 42Hz, the Prime Wireless Pro can go significantly deeper on the low side and provide stronger bass compared to the LSX II's min frequency of 54Hz.
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 Prime Wireless Pro and LSX II 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.
KEF LSX II Port
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 SVS Prime Wireless Pro's and KEF LSX II's external dimensions. SVS Prime Wireless Pro has external dimensions of 295 x 180 x 228mm (11.61 x 7.09 x 8.96 inch) whereas KEF LSX II has external dimensions of 240 × 155 × 180 mm (9.5 × 6.1 × 7.1 inch).
SVS Prime Wireless Pro is clearly the larger of the two speakers. Its body is 25mm wider, 55mm taller and 48mm deeper than KEF LSX II.
Size, drawn to scale
Both speakers and both views share one scale, so everything here is directly comparable. Hover a box for its dimensions.
One scale for both, standing on the same surface and pushed back to the same wall, so the deeper one visibly sticks out further.
SVS Prime Wireless Pro needs about 47% more floor or shelf area. SVS Prime Wireless Pro is 48mm deeper, so it stands that much further out from the wall. SVS Prime Wireless Pro is 55mm taller.
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 SVS Prime Wireless Pro is approximately 410.4cm2 / 63.6inch2 and base area of the KEF LSX II is approximately 279.0cm2 / 43.2inch2. The Prime Wireless Pro requires 47% more surface area than the LSX II which gives it a small disadvantage on placement in tight spaces.
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 SVS Prime Wireless Pro weighs 5.30kg / 11.7lbs and the KEF LSX II weighs 3.60kg / 7.9lbs. This makes the Prime Wireless Pro 47% heavier than the LSX II.
Here is a comparison of how Prime Wireless Pro and LSX II's weights compare with the average, max and min weights in Powered Bookshelf class.
Weight
All Bookshelf Speakers
What's in the Box of SVS Prime Wireless Pro?
Here are the items that are included inside the box of Prime Wireless Pro:
- Active wireless speaker
- 6-feet AC power cord
- Grille (pre-installed)
- 8 Self-adhesive feet
- Active-Passive Speaker Interconnect Cable: 3m / 10ft
- Quick Start Guide
- Warranty/Registration Card
- SVS brochure
- Remote
What's in the Box of KEF LSX II?
Here are the items that come with the LSX II:
- 2 Wireless powered speakers
- Two 6.5-feet AC power cords
- 10-feet Cat-6 interconnect speaker cable
- Remote control
- 2 AAA batteries
- Quick Start Guide
- Important Safety Information
- Warranty Information
- Maintenance Guide
 Woofer Size |
5.25 inches
vs
4.5 inches
|
Larger woofer |
|
Low Frequency Response |
42 Hz
vs
54 Hz
|
Generates deeper bass |
 Price per pair* |
899USD
vs
1299USD
|
costs less (*prices may change depending on the seller, location and time) |
 RCA Connection |
Yes
vs
No
|
Connection via RCA input |
 High Frequency Response |
28k Hz
vs
25k Hz
|
Generates higher frequency |
 Height |
240mm
vs
295mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
279cm2
vs
410cm2
|
Takes less floor space |
| General |
SVS Prime Wireless Pro |
KEF LSX II |
| Brand |
SVS |
KEF |
| Speaker Type |
Powered Stereo Speakers |
Powered Stereo Speakers |
| Frequency Response |
42-25k Hz |
54-28k Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
200-watt RMS |
200-watt RMS |
| Max Bit Depth |
24-bit |
24-bit |
| Max Sample Rate |
192 kHz |
384 kHz |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
5.25" |
4.5" |
| Woofer Composition |
Polypropylen cone |
Magnesium/Aluminium alloy |
| Woofer Surround Material |
n/a |
Rubber |
| Tweeter Size |
1" |
0.75" |
| Tweeter Type |
Dome |
Hard-Dome |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
2000Hz |
n/a |
| Firing Direction |
rear |
rear |
Physical Specs |
|
|
| Height |
295.0mm (11.6") |
240.0mm (9.4") |
| Width |
180.0mm (7.1") |
155.0mm (6.1") |
| Depth |
228.0mm (9") |
180.0mm (7.1") |
| Weight |
5.30kg (11.7lbs) |
3.60kg (7.9lbs) |
| Enclosure |
Bass Reflex |
Bass Reflex |
| Available Colors |
Piano Gloss Black,Piano Gloss White |
Carbon Black, Mineral White, Cobalt Blue, Lava Red, and Soundwave |
| Mounting Bracket |
No |
No |
| Grille |
Yes |
n/a |
| Moisture Resistancy |
No |
No |
Connections |
|
|
| Aux Inputs |
3.5mm, RCA |
3.5mm |
| USB Port |
Service and Powering only |
USB-C (connects to your computer) |
| Phone Input |
No |
No |
| Subwoofer Output |
Wired |
Wired |
| Digital Input |
Optical |
Optical |
| HDMI Input |
ARC,eARC |
ARC |
| Headphone Jack |
No |
No |
| Ethernet Port |
Yes |
Yes |
Other |
|
|
| Parts Warranty |
2 Years |
1 Year |
| Labor Warranty |
2 Years |
1 Year |
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 | A | SVS Prime Wireless Pro digs deeper - 42Hz against 54Hz. |
| Built-in power | evenly matched | Similar onboard amplification (200W vs 200W RMS). |
| Connections | evenly matched | The same set of inputs and streaming options. |
| Size | depends | KEF LSX II is easier to place; SVS Prime Wireless Pro is bigger, which usually goes with fuller bass. Your room decides. |
| Expandability | depends | SVS Prime Wireless Pro: a sub output; KEF LSX II: a sub output. |
| Price | A | SVS Prime Wireless Pro is cheaper - $899 against $1,299, about 31% less. |
A SVS Prime Wireless Pro B KEF LSX II
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?
SVS Prime Wireless Pro has the edge on paper, though the margin is not large. The rows marked "depends" may matter more to you than the score does. If a subwoofer is in your plans, the bass gap largely stops mattering - you would be crossing over above 54Hz anyway, so judge these on the other rows instead. In a large or open-plan room, SVS Prime Wireless Pro has the cabinet volume to fill it more easily; in a small room, near a wall or at desk distance, KEF LSX II is the easier speaker to get right.
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.