In this review, we will be comparing Borea BR02 BT and R-51PM, two Powered Bookshelf speakers from Triangle and Klipsch. 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 Triangle Borea BR02 BT and Klipsch R-51PM first before getting into our more
detailed comparison.
| Key Specs | Triangle Borea BR02 BT | Klipsch R-51PM |
|---|
| Brand | Triangle
France · founded 1980 | Klipsch
United States · founded 1946 |
|---|
| Design | 2-way | 2-way |
|---|
| Built-in amplifier | 120-watt RMS | 120-watt RMS (240-watt peak) |
|---|
| Tweeter | 1" Dome | 1.0" Tractrix Horn |
|---|
| Woofer | 5" fiberglass | 5.25" Copper-spun IMG |
|---|
| Frequency response | 47-22kHz | 68-21k Hz |
|---|
| Sensitivity | 90dB | — |
|---|
| Max depth / sample rate | 24-bit / 48 kHz | 24-bit / 96 kHz |
|---|
| Bluetooth | Built-in 5.0 | Built-in 3.0 |
|---|
| Weight | 10.20kg / 22.4lbs | 4.80kg / 10.6lbs |
|---|
| Dimensions (H x W x D) | 12.2" x 6.9" x 10.8"
310.0 x 176.0 x 274.0mm | 13" x 7.0625" x 10.25"
330.2 x 179.4 x 260.3mm |
|---|
The sections below take each area in turn: drivers, frequency response, physical size and what you get in the box.
Drivers
Both Borea BR02 BT and R-51PM are 2-way speakers.
Triangle Borea BR02 BTKlipsch R-51PM
TweeterWoofer
Front view, drawn to scale - cabinets and drivers share one scale, so sizes are directly comparable. Hover a driver for its size.
| Driver |
Triangle Borea BR02 BT |
Klipsch R-51PM |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1-inch
|
1.0-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
1 x 5-inch
|
1 x 5.25-inch
|
Borea BR02 BT features a 1" EFS fabric Dome Tweeter and 1 x 5" fiberglass Woofer. On the other hand, the R-51PM features a 1.0" Aluminum LTS Tractrix Horn Tweeter and 1 x 5.25" Copper-spun IMG Woofer with a Crossover frequency at 1663Hz.
Frequency Response
Borea BR02 BT has a frequency range of 47-22kHz whereas R-51PM has a frequency range of 68-21k Hz. With a minimum frequency of 47Hz, the Borea BR02 BT can go significantly deeper on the low side and provide stronger bass compared to the R-51PM's min frequency of 68Hz.
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 Borea BR02 BT and R-51PM 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 Triangle Borea BR02 BT's and Klipsch R-51PM's external dimensions. Triangle Borea BR02 BT has external dimensions of 310.0 x 176.0 x 274.0mm (8.1x 14.1 x 12.36 inches) whereas Klipsch R-51PM has external dimensions of 330.2 x 179.4 x 260.3mm (13 x 7.0625 x 10.25inch).
Triangle Borea BR02 BT is 3.4mm narrower and 20.2mm shorter than Klipsch R-51PM but it is also 13.7mm deeper.
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.
Near-identical footprints. Klipsch R-51PM is 20mm 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 Triangle Borea BR02 BT is approximately 482.2cm2 / 74.7inch2 and base area of the Klipsch R-51PM is approximately 467.0cm2 / 72.4inch2. The Borea BR02 BT requires 3% more surface area than the R-51PM 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 Triangle Borea BR02 BT weighs 10.20kg / 22.4lbs and the Klipsch R-51PM weighs 4.80kg / 10.6lbs. This makes the Borea BR02 BT 113% heavier than the R-51PM.
Here is a comparison of how Borea BR02 BT and R-51PM's weights compare with the average, max and min weights in Powered Bookshelf class.
Weight
All Bookshelf Speakers
What's in the Box of Triangle Borea BR02 BT?
Here are the items that are included inside the box of Borea BR02 BT:
- 1 x passive loudspeaker BOREA BT cable to link the loudspeakers 8. 1 x user manual
- 1 x active loudspeaker BOREA BT (indicator light on the front)
- 2 x protection grills
- 1 x remote control, incl. 2 AAA batteries
- 8 x adhesive anti-slip feet to place below the speakers
- 1 x AC power cord
- 1 x 3 meters speaker
What's in the Box of Klipsch R-51PM?
Here are the items that come with the R-51PM:
- Powered speaker (right)
- Passive speaker (left)
- 2 Grilles
- 68-inch AC power cord
- Remote control
- 2
 Low Frequency Response |
47 Hz
vs
68 Hz
|
Generates deeper bass |
 High Frequency Response |
22k Hz
vs
21k Hz
|
Generates higher frequency |
 Height |
310mm
vs
330mm
|
Easier to fit in smaller spaces |
 Price per pair* |
499USD
vs
599USD
|
costs less (*prices may change depending on the seller, location and time) |
|
Woofer Size |
5.25 inches
vs
5 inches
|
Larger woofer |
 Base Surface Area |
467cm2
vs
482cm2
|
Takes less floor space |
 USB Port |
USB-B
vs
No
|
USB port adds flexibility |
| General |
Triangle Borea Active BR02 BT |
Klipsch Reference R-51PM |
| Brand |
Triangle |
Klipsch |
| Speaker Type |
Powered Stereo Speakers |
Powered Stereo Speakers |
| Sensitivity |
90dB |
n/a |
| Impedance |
4.2 ohms |
n/a |
| Frequency Response |
47-22kHz |
68-21k Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
120-watt RMS |
120-watt RMS |
| Watts Peak (Max) |
n/a |
240-watt RMS |
| Max Bit Depth |
24-bit |
24-bit |
| Max Sample Rate |
48 kHz |
96 kHz |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
5" |
5.25" |
| Woofer Composition |
fiberglass |
Copper-spun IMG |
| Tweeter Size |
1" |
1.0" |
| Tweeter Type |
Dome |
Tractrix Horn |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
n/a |
1663Hz |
| Firing Direction |
rear |
rear |
Physical Specs |
|
|
| Height |
310.0mm (12.2") |
330.2mm (13") |
| Width |
176.0mm (6.9") |
179.4mm (7.1") |
| Depth |
274.0mm (10.8") |
260.3mm (10.2") |
| Weight |
10.20kg (22.4lbs) |
4.80kg (10.6lbs) |
| Enclosure |
Bass Reflex |
Bass Reflex |
| Available Colors |
Light Oak Blue,Oak Green,Cream,Light Oak,Black |
n/a |
| Mounting Bracket |
No |
No |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
| Aux Inputs |
3.5mm, RCA |
3.5mm, RCA |
| USB Port |
No |
USB-B |
| Phone Input |
Yes |
Yes |
| Subwoofer Output |
mono-RCA |
Wired |
| Digital Input |
Optical,Coaxial |
Optical |
| HDMI Input |
No |
No |
| Headphone Jack |
No |
No |
| Ethernet Port |
No |
No |
Other |
|
|
| Parts Warranty |
5 Years |
1 Year |
| Labor Warranty |
5 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 | Triangle Borea BR02 BT digs deeper - 47Hz against 68Hz. |
| Built-in power | evenly matched | Similar onboard amplification (120W vs 120W RMS). |
| Connections | evenly matched | The same set of inputs and streaming options. |
| Size | depends | Similar cabinet size - neither is easier to fit. |
| Expandability | depends | Triangle Borea BR02 BT: a sub output; Klipsch R-51PM: a sub output. |
| Price | A | Triangle Borea BR02 BT is cheaper - $499 against $599, about 17% less. |
A Triangle Borea BR02 BT B Klipsch R-51PM
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?
Triangle Borea BR02 BT 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 68Hz anyway, so judge these on the other rows instead.
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.