In this review, we will be comparing The Nines and R-51PM, two Powered Bookshelf speakers by 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 Klipsch The Nines and Klipsch R-51PM first before getting into our more
detailed comparison.
In the following sections, we will get into more detail in order to better understand how the Klipsch The Nines and Klipsch R-51PM compare and hopefully end up with enough arguments to decide which one of these loudspeakers is the better choice for you.
**This post contains affiliate links, and I will be compensated if you make a purchase after clicking
through my links. As an Amazon Associate I earn from qualifying purchases.
Drivers
Both The Nines and R-51PM are 2-way speakers.
| Driver |
Klipsch The Nines |
Klipsch R-51PM |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1-inch
|
1.0-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
1 x 8-inch
|
1 x 5.25-inch
|
The Nines features a 1" Titanium Tractrix Horn Tweeter and 1 x 8" Fiber-composite 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
The Nines has a frequency range of 34-25k Hz whereas R-51PM has a frequency range of 68-21k Hz. With a minimum frequency of 34Hz, the The Nines can go significantly deeper on the low side and provide stronger bass compared to the R-51PM's min frequency of 68Hz.
Below graphs depict how these two speakers compare with the max, min and average values of the Min and Max Frequencies of other speakers in the Bookshelf class in our database.
Low Frequency
Bookshelf Speakers
High Frequency
Bookshelf Speakers
None of these speakers achieves full range experience which is commonly agreed as 20Hz-20kHz. In order to achieve lower lows / deeper bass, we recommend you pair these with a subwoofer. Visit our Powered Subwoofers section to find out more about the available options.
Cabinet Type and Port Position
Both The Nines 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
Size of a speaker can sometimes become an important decision factor due to space constraints or in some cases purely for esthetic reasons. In this section, we are going to compare Klipsch The Nines's and Klipsch R-51PM's external dimensions. Klipsch The Nines has external dimensions of 493.0 x 243.0 x 399.0mm ( 19.375inch x 9.5625inch x 15.6875inch ) whereas Klipsch R-51PM has external dimensions of 330.2 x 179.4 x 260.3mm ( 13 x 7.0625 x 10.25inch) .
Klipsch The Nines is clearly the larger of the two speakers. Its body is 63.6mm wider, 162.8mm taller and 138.7mm deeper than Klipsch R-51PM.
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 Klipsch The Nines is approximately 969.6cm2 / 150.3inch2 and base area of the Klipsch R-51PM is approximately 467.0cm2 / 72.4inch2. The The Nines requires 108% 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 Klipsch The Nines weighs 12.25kg / 27lbs and the Klipsch R-51PM weighs 4.80kg / 10.6lbs. This makes the The Nines 155% heavier than the R-51PM.
Here is a comparison of how The Nines 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 Klipsch The Nines?
Here are the items that are included inside the box of The Nines:
Powered speaker (Primary) Passive speaker (Secondary) 2 Grilles (pre-installed) 6.5-feet AC power cord 13-feet Proprietary speaker cable 6.5-feet Proprietary extension cable 58-inch HDMI cable 5-feet USB-B to USB-A cable Remote control 2 AAA batteries Instruction Booklet Need Help? Card
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 Grilles68-inch AC power cordRemote control2
 Woofer Size |
8 inches
vs
5.25 inches
|
Larger woofer |
| Low Frequency Response |
34 Hz
vs
68 Hz
|
Generates deeper bass |
 High Frequency Response |
25k Hz
vs
21k Hz
|
Generates higher frequency |
 App-Based Control |
Apple iOS, Android
vs
None
|
Control the speaker via an app |
 USB Port |
USB-B
vs
No
|
USB port adds flexibility |
 HDMI Input |
ARC
vs
No
|
Connect HDMI sources directly |
 Height |
330mm
vs
493mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
467cm2 (179x260mm)
vs
969cm2 (243x399mm)
|
Takes less floor space |
 Price per pair* |
599USD
vs
1499USD
|
costs less (*prices may change depending on the seller, location and time) |
| USB Port |
USB-B
vs
No
|
USB port adds flexibility |
 RCA Connection |
Yes
vs
No
|
Connection via RCA input |
| General |
Klipsch The Nines |
Klipsch Reference R-51PM |
| Brand |
Klipsch |
Klipsch |
| Speaker Type |
Powered Stereo Speakers |
Powered Stereo Speakers |
| Frequency Response |
34-25k Hz |
68-21k Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
240-watt RMS |
120-watt RMS |
| Watts Peak (Max) |
480-watt RMS |
240-watt RMS |
| Max Bit Depth |
24-bit |
24-bit |
| Max Sample Rate |
192 kHz |
96 kHz |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
8" |
5.25" |
| Woofer Composition |
Fiber-composite |
Copper-spun IMG |
| Tweeter Size |
1" |
1.0" |
| Tweeter Type |
Tractrix Horn |
Tractrix Horn |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
n/a |
1663Hz |
| Firing Direction |
rear |
rear |
Physical Specs |
|
|
| Height |
493.0mm (19.4") |
330.2mm (13") |
| Width |
243.0mm (9.6") |
179.4mm (7.1") |
| Depth |
399.0mm (15.7") |
260.3mm (10.2") |
| Weight |
12.25kg (27lbs) |
4.80kg (10.6lbs) |
| Enclosure |
Bass Reflex |
Bass Reflex |
| Finish |
MDF with genuine wood veneer |
n/a |
| Available Colors |
Black,Walnut |
n/a |
| Mounting Bracket |
No |
No |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
| Aux Inputs |
3.5mm |
3.5mm, RCA |
| USB Port |
USB-B |
USB-B |
| Phone Input |
Yes |
Yes |
| Subwoofer Output |
mono-RCA |
Wired |
| Digital Input |
Optical, HDMI |
Optical |
| HDMI Input |
ARC |
No |
| Headphone Jack |
No |
No |
| Ethernet Port |
No |
No |
Other |
|
|
| Parts Warranty |
1 Year |
1 Year |
| Labor Warranty |
1 Year |
1 Year |